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An Investigation Analysing the Perceivable Differences between Analogue and Digital Audio Equipment on a Piece of Music. Faculty of Arts and Creative Technologies. By Scott Probert 10022259 BSc (HONS) Music Technology Supervisor: Doug Rouxel May 2014 Word Count (8794/8000) CE700576

Dissertation: Analysing the Perceivable Differences Between Analogue and Digital Audio Equipment on a Piece of Music

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Page 1: Dissertation:  Analysing the Perceivable Differences Between Analogue and Digital Audio Equipment on a Piece of Music

 An  Investigation  Analysing  the  Perceivable  Differences  between  Analogue  and  Digital  Audio  Equipment  on  a  

Piece  of  Music.            

             

 Faculty  of  Arts  and  Creative  Technologies.  

           

By  Scott  Probert    

10022259      

BSc  (HONS)  Music  Technology    

Supervisor:    Doug  Rouxel    

May  2014          

Word  Count  (8794/8000)    

CE70057-­‐6  

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Abstract                      

 The  purpose  of  this  investigation  is  to  ascertain  whether  or  not  a  piece  of  music  will  benefit  from  introducing  analogue  signal  processors  at  the  different  stages  of  music  production.    With  digital  signal  processing  (DSP)  becoming  more  prevalent  in  the  world  of  music  production  due  to  the  recent  advancements  in  digital  technology  and  the  availability  of  DSPs  within  digital  audio  workstations  (DAWs).    More  and  more  producers’  are  now  producing  tracks  entirely  within  a  DAW.    For  the  relatively  cheap  cost  of  using  the  DSPs  provided  within  a  DAW  compared  to  hiring  a  top  end  studio  to  produce  a  piece  of  music,  it  is  time  to  find  out  whether  the  quality  of  music  is  been  affected.              This  investigation  aims  to  provide  producers’  with  answers  as  to  whether  listeners’  actually  prefer  music  produced  entirely  within  a  DAW  or  with  the  introduction  of  analogue  signal  processors.    The  investigation  will  involve  mixing  and  mastering  a  track  using  both  analogue  and  digital  signal  processors  in  the  following  ways:    

• Digital  Mix/Digital  Master  • Digital  Mix/Analogue  Master  • Analogue  Mix/Analogue  Master  • Analogue  Mix/Digital  Master  

 Accompanied  by  a  controlled  listening  test  and  survey  that  can  provide  additional  information  as  to  why  listeners’  prefer  the  version  they  do,  the  investigation  should  be  seen  as  a  guide  for  producers’  who  are  having  difficulty  deciding  which  signal  processing  method  to  use.    The  investigations  aim  is  to  allow  producers’  to  make  informed  decisions  based  on  the  results  of  the  investigation  for  their  future  productions  that  will  make  their  music  more  appealing  to  the  public.    

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Acknowledgements                

 Thanks  go  to  the  following  people  for  their  assistance  in  the  production  of  this  investigation  and  recordings  made.    Doug  Rouxel  –  For  the  supervision,  guidance  and  advice  given  throughout  the  production  of  this  investigation.    Thomas  Frew  –  For  the  assistance  in  performing  the  analogue  mix  and  advice  on  the  techniques  used.    Adam  Brown  –  For  the  assistance  in  recording  some  of  the  sounds  used  in  the  production  of  the  track  as  well  as  the  critical  feedback  received  on  the  production  techniques  used.    Staffordshire  University  –  For  providing  the  facilities  to  perform  produce  the  recordings  made  for  this  investigation.    Amanda  Drennan  –  For  assistance  in  collating  the  data  of  the  listening  tests.    To  all  the  manufacturers  of  the  equipment  used  as  specified  in  the  ‘Equipment  List’,  which  can  be  found  in  ‘Appendices  8.2’.    To  all  the  participants  in  the  listening  test  and  survey  who  shall  remain  anonymous,  without  them  this  investigation  would  not  have  been  possible.      

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Contents                      

 ABSTRACT  ..........................................................................................................................................  2  ACKNOWLEDGEMENTS  ..................................................................................................................  3  CONTENTS  ..........................................................................................................................................  4  TABLE  OF  FIGURES  ..........................................................................................................................  5  1  -­‐  INTRODUCTION  ..........................................................................................................................  6  2  -­‐  TECHNICAL  CONSIDERATIONS  ..............................................................................................  7  2.1  -­‐  DSPS.  ..........................................................................................................................................................  7  2.2  -­‐  ANALOGUE  SIGNAL  PROCESSORS.  .........................................................................................................  8  

3  -­‐  RESEARCH  AND  PROCESS  .....................................................................................................  10  3.1  -­‐  PRODUCING  THE  TRACK.  .....................................................................................................................  10  3.2  -­‐  PERFORMING  THE  MIX.  ........................................................................................................................  11  3.2.1  -­‐  Preliminary  Work.  ........................................................................................................................  11  3.2.2  -­‐  The  Aim  of  the  Mix.  ......................................................................................................................  11  3.2.4  -­‐  Digital  Mix.  ......................................................................................................................................  12  3.2.5  -­‐  Analogue  Mix.  .................................................................................................................................  13  

3.3  -­‐  PERFORMING  THE  MASTER.  ................................................................................................................  13  3.3.1  -­‐  Digital  Master.  ...............................................................................................................................  15  3.3.2  -­‐  Analogue  Master.  ..........................................................................................................................  15  

4  -­‐  TESTING  METHODOLOGY  ....................................................................................................  17  4.1  -­‐  RESEARCH.  .............................................................................................................................................  17  4.1.1  -­‐  ‘ABX’  Testing.  ..................................................................................................................................  17  4.1.2  -­‐  Qualitative  Research.  ..................................................................................................................  17  4.1.3  -­‐  Quantitative  Research.  ...............................................................................................................  18  

4.2  -­‐  CHOSEN  TESTING  METHOD.  ................................................................................................................  18  4.2.1  -­‐  Producing  the  Listening  Test.  ..................................................................................................  18  4.2.2  -­‐  Producing  the  Survey.  .................................................................................................................  20  

5  -­‐  RESULTS  .....................................................................................................................................  23  5.1  -­‐  ANALYSIS  OF  THE  DATA  COLLECTED.  ...............................................................................................  23  5.2  -­‐  CONCLUSION.  .........................................................................................................................................  26  

6  -­‐  EVALUATION  ............................................................................................................................  29  7  -­‐  BIBLIOGRAPHY  ........................................................................................................................  31  8  -­‐  APPENDICES  .............................................................................................................................  36  8.1  -­‐  FURTHER  READING.  ..............................................................................................................................  36  8.1.1  –  Books.  ................................................................................................................................................  36  8.1.2  –  Journals.  ...........................................................................................................................................  37  8.1.3  –  Magazines.  ......................................................................................................................................  37  8.1.4  –  Websites.  ..........................................................................................................................................  37  

8.2  -­‐  EQUIPMENT  LIST.  ..................................................................................................................................  38  8.3  -­‐  SCREENSHOTS.  .......................................................................................................................................  39  8.4  -­‐  COMPLETED  QUESTIONNAIRES.  .........................................................................................................  40  

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Table  of  Figures                  

 Figure  1.1  –  Table  showing  some  descriptive  words  for  musical  instruments………………………………………………………………………………………………….22    Figure  2.1  –  Graph  showing  the  versions  that  are  most  and  least  preferred  by  the  test  subjects’……………………………………………………………………………………………..………...23    Figure  2.2  –  Graph  showing  the  age  range  and  gender  of  subjects’  that  choose  versions  1  and  3…………………………………………………………………………………….……...24  

Figure  2.3  –  Graph  showing  the  descriptive  words  used  when  describing  both  versions  1  and  3…………………………………………………………………………………..………..25  

Figure  3.1  –  Screenshot  of  the  edit  window  of  the  structured  project……………..39  

Figure  3.2  –  Screenshot  of  recorded  percussion  and  Rhodes  sample………………39  

Figure  3.3  –  Screenshot  of  the  VST  used  for  the  creation  of  one  of  the  bass  parts  for  the  project……………………………………………………………………………………..………..40  

             

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1  -­‐  Introduction                  

     “In  the  good  old  days  of  professional  recording  a  studio  was  built  around  an  

analogue  mixer,  a  2-­‐inch  analogue  multitrack  recorder,  a  pair  of  monitors,  and  some  outboard  effects”  (White,  1998).  

 Engineers  such  as  ‘Nirvana’s’  Steve  Albini  still  records  to  analogue  tape  believing  that  “today’s  digital  recordings  will  be  unplayable  in  the  future”(Guttenburg,  2013).              However,  today  this  is  not  common  practice  and  though  most  artists’  use  analogue  equipment  to  record  (like  micing  up  an  amp),  the  signal  is  recorded  and  stored  digitally  as  binary  code  using  a  DAW.    Today,  due  to  recent  technological  advancements,  most  people  record,  mix,  and  master  entirely  within  a  DAW  and  the  binary  information  that  represents  the  sounds  never  return  to  an  analogue  signal  (except  for  monitoring)  until  it  leaves  the  listeners’  speakers  (Hamasaki,  et  al,  2012,  p.94).      While  now  commonly  accepted  that  the  recording  process  will  involve  a  digital  representation  being  made  within  a  DAW,  more  artists’  are  now  choosing  to  record  their  LPs  from  the  very  first  note  in  an  analogue  environment  and  it’s  renewed  popularity  suggests  some  listeners’  may  be  tired  of  MP3s  squeezed  sonics  (Yu,  et  al,  2004,  pp.1-­‐14).      Audio  Engineering  Society  (AES)  member  Sterne  (2006)  believes  the  perceivable  differences  between  analogue  and  digital  audio  are  a  philosophical  debate  among  academics,  journalists  and  audiophiles.    Believing  that  the  debate  is  simply  an  anxiety,  and  fear,  of  loss  of  audio  quality  as  it  passes  through  many  signal  processors  from  the  time  it  is  produced  to  the  time  it  reaches  the  listener’s  ears  (Sterne,  2006,  pp.338-­‐348).    Considering  most  recordings  are  converted  to  a  digital  format  almost  instantly,  this  project  will  help  advise  artists  as  to  whether  their  recordings  will  benefit  from  introducing  analogue  processing  at  the  mixing  and/or  mastering  stages  of  a  production.      

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2  -­‐  Technical  Considerations              

 As  the  investigation  will  replicate  a  commercial  recording  environment,  whether  utilising  DSPs  provided  within  a  DAW,  outboard  analogue  processors  or  a  combination  of  both.    The  equipment  used  will  need  to  replicate  the  equipment  used  throughout  the  music  industry  that  utilise  both  analogue  and  digital  signal  processors.          The  university  offers  the  facilities  to  utilise  both  analogue  and  digital  processors  used  throughout  the  music  industry  by  artists’  that  have  had  commercial  success.          Following  is  an  explanation  of  these  processes  and  how  they  are  used  throughout  the  music  industry.    

2.1  -­‐  DSPs.    As  “mechanical  equipment  can  be  expensive  or  impossible  to  acquire,  and  a  hassle  to  maintain  or  use”  (Robjohns,  2010),  it  is  unsurprising  that  DSPs  are  now  the  most  common  method  for  processing  audio  (Brandenburg,  1998,  p.1).    One  significant  advantage  of  using  DSPs  is,  unlike  analogue  processors,  digital  plugin  processors  allow  custom  settings  to  be  saved  and  recalled  for  future  use.    These  settings  can  also  be  edited  to  accommodate  almost  any  situation  making  them  very  versatile  for  producers  as  well  as  mixing  and  mastering  engineers’    (Levine  &  Skolnick,  1997,  pp.1-­‐23).    Recent  years  have  seen  the  continuation  of  the  shift  from  using  analogue  signal  processors  to  DSPs  within  the  professional  audio  products  market  (Floru,  2005,  pp.1-­‐16).  Due  to  the  performance  improvements  in  solid-­‐state  memory,  disk  drives  and  microprocessors,  the  performance  capabilities  of  modern  DSPs  has  got  to  a  stage  that  is  now  comparable  to  their  analogue  counterparts  making  them  a  popular  choice  for  music  producers’  (Johnston  &  Musialik,  2012,  pp.104-­‐105).  One  criticism  of  using  DSPs  is  that,  although  many  parameters  can  be  automated  to  change  on  playback  simultaneously,  it  requires  the  input  of  data  through  the  use  of  a  keyboard  or  mouse  and  the  limitation  is  that  only  one  single  control  can  be  changed  at  any  single  time  without  the  use  of  a  digital  controller.              This  method  is  often  seen  as  too  clinical  and  precise  and  doesn’t  capture  the  ‘more  human’  feel  of  analogue  mixing  techniques  (Robjohns,  2013,  p.26).    As  Avid’s  ‘Pro  Tools’,  Imageline’s  ‘FL  Studio’  and  Apple’s  ‘Logic  Pro’  are  now  the  most  popular  DAWs  (Stillman,  2013),  it  means  that  the  plugins  bundled  with  the  DAWs  are  now  owned  and  utilised  by  many  people.    This  means  the  characteristics  of  each  plugin  are  now  embedded  on  many  tracks  heard  by  the  public.    This  compared  to  the  varying  factors  that  can  affect  the  characteristics  of  analogue  processors  can  result  in  music  having  the  same  characteristics  due  to  the  plugins  that  are  used  (Kirn,  2013).  

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2.2  -­‐  Analogue  Signal  Processors.    Using  analogue  processors  during  any  stage  of  a  production  can  cause  some  issues.    While  allowing  the  user  to  become  more  involved  in  the  process  with  hands-­‐on  controls  utilising  more  of  the  users  senses  such  as  tactile  feedback  (Altinsoy,  et  al,  2010,  pp.1-­‐7).    It  can  have  practical  downfalls  requiring  the  user  to  employ  their  own  system  for  remembering  settings  and  routing.    This  requires  good  organisational  skills  such  as  taking  notes  and  pictures  to  allow  settings  and  routing  to  be  replicated  in  future  sessions.    Although  modern  DSPs  are  now  often  cheaper  and  affect  the  signals  differently  to  their  analogue  counterparts,  many  companies  still  produce  analogue  audio  equipment  that  are  priced  to  compete  with  modern  DSPs  (Sterne,  2006,  pp.338-­‐348).              Often  these  lower  priced  analogue  processors  have  unbalanced  inputs  meaning  that  the  tip  and  ring  are  ‘hot’  and  the  other  is  the  reference  or  ground.    This  type  of  design  cannot  reject  common  mode  signals  present  in  the  signal  wire  as  well  as  in  the  ground  pin.    This  can  result  in  unwanted  noise  being  added  to  the  signal,  and  when  used  the  signal  is  often  boosted  resulting  in  the  unwanted  noise  been  boosted  as  well  (Floru,  2005,  pp.1-­‐16).              To  combat  this  problem  balanced  inputs  are  used  which  reject  the  common  mode  signal  and  amplifies  the  differential  signal  resulting  in  a  cleaner  sound  as  the  ground  wire  does  not  carry  a  signal  and  any  currents  flowing  through  the  ground  pin  do  not  interfere  with  the  signal.    However,  this  raises  production  costs  and  can  drive  up  the  price  of  the  unit  making  some  units  less  competitive  with  their  digital  counterparts.    Cheaper  analogue  signal  processors  also  find  it  hard  to  perform  as  well  as  their  digital  competitors  as  designing  an  analogue  signal  processor  can  challenge  a  design  team’s  ability  to  meet  both  cost  and  performance  requirements  (Murphy,  2013).    Trying  to  avoid  high  production  costs,  cheaper  components  are  used  and  less  shielding  is  implemented  making  them  more  susceptible  to  noise  due  to  power  supply  variations,  electromagnetic  interference  (EMI)  and  radio  frequency  interference  (RFI).    These  unwanted  signals  can  be  caused  by  many  common  aspects  of  the  modern  world  such  as:    

• Radio  and  Television  (TV)  broadcasts  • Mobile  radio  communications  • Mobile  telephones  • Lighting  • Utility  power  lines  • Electric  motors  • Computers  (Jung,  2005,  pp.686-­‐852).  

 As  most  of  these  signals  are  unavoidable,  it  is  especially  important  that  equipment  used  is  as  protected  as  possible  from  these  unwanted  interferences.    This  makes  the  cheaper  analogue  signal  processors  undesirable  to  many  producers  who  would  rather  use  DSP  plugins  within  the  same  price  range  that  

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can  emulate  the  characteristics  of  classic  analogue  processors  rather  than  open  their  audio  up  to  these  unwanted  interferences  (Lambert,  2010).          This  is  why  many  analogue  signal  processors  used  by  industry  professionals  in  the  top  studios  around  the  world  like  the  Fairchild  ‘670’  compressor  and  Manley’s  ‘Massive  Passive’  equaliser  (EQ),  although  susceptible  to  RFI  are  relatively  more  expensive  and  can  fetch  around  £5000  -­‐  £30,000  second  hand  making  them  harder  to  come  by  for  most  people  who  have  entered  the  music  production  world  through  the  availability  of  common  and  relatively  cheap  DAWs.    Using  analogue  equipment  requires  the  signal  to  be  (whether  sound  waves  or  binary  information)  turned  into  voltages  to  be  processed.    This  is  where  the  ‘analogue  warmth’  in  some  analogue  processors  is  added  to  the  signal.    Each  component  in  the  system,  as  well  as  the  cables  used,  “will  have  specific  frequency  response  characteristics,  and  will  therefore  modify  the  signal  to  some  degree”  (Davis  &  Jones,  1990,  p.12).    These  characteristics,  which  are  often  seen  as  imperfections  in  the  system,  can  also  introduce  harmonic  distortion  and  a  “significant  roll-­‐off  above  the  cutoff  frequency  of  the  device”  (Davis  &  Jones,  1990,  p.13)  that  adds  the  character  of  the  processor  to  the  signal.    It  is  this  process  that  “adds  a  character  which  makes  a  significant  improvement  in  the  basic  sound  of  the  track  being  processed”  resulting  in  “less  EQ  or  compression  being  needed,  preserving  the  quality  of  the  original  sound”  (Kemp,  2000,  p.1).    This  can  help  producers’  achieve  sounds  individual  to  them  helping  their  track  standout  and  become  harder  to  replicate  giving  them  an  edge  on  the  competition.    Although  sometimes  improving  the  sound,  most  analogue  processors  due  to  the  components  used  can  sometimes  be  unpredictable  and  sound  different  each  time  they  are  used.    This  is  due  to  the  components  becoming  warm  and  worn  out  through  use.    This  can  change  the  noise  levels  and  characteristics  of  the  equipment  producing  unexpected  and  sometimes  undesirable  results.      

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3  -­‐  Research  and  Process              

 Although  the  track  used  will  be  the  same  recording  for  the  four  different  processing  methods,  each  process  will  be  treated  as  an  individual  session  independent  from  its  analogue  or  digital  counterpart.      This,  due  to  the  different  equipment  that  will  be  used,  will  ensure  the  best  possible  outcome  for  each  method  and  will  take  into  account  the  different  processing  methods  for  each  piece  of  equipment  used.    

3.1  -­‐  Producing  the  Track.    The  availability  and  ease  of  use  of  the  modern  DAW  has  made  music  production  a  viable  option  for  anybody  interested  in  music  to  become  involved  in  all  stages  of  music  production.    Widely  used  for  audio  production,  modern  DAWs  can  be  purchased  quite  inexpensively  and  by  non-­‐legal  means  for  free  (Hamaski,  et  al,  2012,  p.94).    The  track  used  for  this  project  was  created  in  Apple’s  ‘Logic  Pro  9.1.8’.    Currently  available  for  purchase  on  Apple’s  ‘App  Store’  for  £139.99  (as  of  March  2014)  making  it  relatively  cheap  compared  to  other  DAWs  available  such  as  Propellerhead’s  ‘Reason  7’  and  Avid’s  ‘Pro  Tools  11’  with  recommended  retail  prices  (RRP)  of  £349  and  £550  respectively  making  it  a  popular  choice  amongst  new  producers’  (Try,  2011).            Considering  the  nature  of  the  investigation  it  is  important  that  the  recording  will  not  bias  the  outcome.    For  this  reason  the  track  was  produced  using  neither  completely  analogue  nor  completely  digital  recording  methods  and  instead  incorporated  both.          Using  a  mixture  of  analogue  drums  and  keys  samples  alongside  digitally  produced  sounds  for  bass  and  synths  allowed  the  track  to  not  be  influenced  too  dramatically  towards  one  side  or  another.    As  the  purpose  of  the  investigation  is  to  analyse  the  sonic  differences  between  analogue  and  digital  processing  it  is  important  to  use  a  mixture  of  both  recorded  sounds  and  digital  sounds  to  not  bias  the  test  from  the  start.      

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3.2  -­‐  Performing  the  Mix.    To  achieve  a  good  mix  it  is  believed  that  preliminary  work  is  beneficial  to  the  creative  process  and  is  key  to  the  process  running  smoothly  (Bennett,  2005).    

3.2.1  -­‐  Preliminary  Work.    The  individual  tracks  were  exported  in  the  stereo  interleaved  waveform  audio  file  format  (WAVE)  with  a  bit  depth  and  sample  rate  of  16Bit  44.1kHz  ensuring  that  the  tracks  retain  the  original  quality  as  when  they  were  created.        Along  with  setting  up  auxiliary  buss  channels  for  drums,  bass,  sub  bass,  synths  and  incidental  sounds,  the  creative  workflow  of  the  project  is  ready  for  the  mixing  process  (Altinsoy,  et  al,  2010,  pp.1-­‐7).              This  process  was  carried  out  for  both  the  analogue  and  digital  mix  projects  and  although  it  initially  seems  unnecessary,  it  is  believed  that  this  simple  preliminary  process  can  increase  creativity  by  allowing  the  “more  technical  ‘left-­‐brain’  activity  to  be  out  of  the  way”  (Lockwood,  White  &  Robjohns,  2013,  p.197)  allowing  the  more  creative  ‘right-­‐brain’  to  work  more  efficiently  and  save  time  as  well  as  CPU  (Thornton,  2007).    Using  a  reference  track  that  has  already  proven  to  work  within  the  genre  is  good  practice  and  allows  a  reference  point  for  the  mix  to  be  performed  by  providing  a  goal  for  the  mix  (Johnston  &  Spors,  2012,  pp.105-­‐106).              The  reference  track  used  for  this  project  is  ‘Let  Me  Hold  You’  by  the  artist  ‘Calibre’  (2009)  who  is  an  established  artist  within  the  ‘Drum  and  Bass’  genre.    

3.2.2  -­‐  The  Aim  of  the  Mix.    ‘Although  common  mixing  techniques  can  be  taught  the  art  of  mixing  is  not  purely  an  analytical  process  that  can  be  calculated  to  provide  a  solution’  (Sandler,  et  al,  

2014,  pp.4-­‐13).    

Mixing  can  be  described  as  “the  process  of  putting  multiple  layers  of  audio  together  to  make  one  final  track”  (Tromp,  2011).    The  important  element  to  remember  is  layers.    As  most  tracks  will  have  many  layers  all  fighting  for  space,  it  is  important  that  decisions  are  made  as  to  which  elements  require  the  listener’s  attention.              This  involves  using  EQ,  dynamic  range  processors,  volume  control  and  phase  based  imaging  processors  to  create  a  track  that  has  space  for  each  sound  to  breathe  and  stand  out  to  the  listener  when  necessary.    This  will  allow  listening  to  the  track  to  become  an  immersive  experience  that  captures  the  listener’s  attention  helping  them  feel  part  of  the  track  (Scott  &  Youngmoo,  2013,  pp.1-­‐6).    As  well  as  being  given  the  control  of  all  the  components  of  the  track  creatively,  it  is  also  the  responsibility  of  the  mix  engineer  to  ensure  the  mix  is  correct  technically.    This  means  ensuring  that  no  tracks  are  clipping,  there  is  enough  

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headroom  for  the  mix  to  compete  with  similar  tracks  within  the  genre  and  that  the  noise  floor  is  as  inaudible  as  possible.    This  requires  consideration,  and  a  trade-­‐off  between  the  technical  and  creative  aspects  of  a  mix  should  be  made  according  to  the  artistic  objectives  of  both  the  artist  and  mix  engineer  (Sandler,  et  al,  2014,  pp.4-­‐13).    However,  as  the  main  goal  for  any  song  is  that  listener’s  enjoy  it,  listener’s  expectations  should  be  considered.    This  raises  an  issue  for  the  mix  engineer,  as  they  must  attempt  to  mix  for  as  many  possible  listening  environments  as  possible.              As  the  mix  engineer,  at  this  stage,  doesn’t  know  whether  the  track  will  be  listened  to  through  a  large  ‘PA’  system  or  a  small  mono  kitchen  radio.    It  is  the  job  of  the  mix  engineer  to  ensure  that  the  track  translates  well  through  as  many  different  playback  systems  as  possible.    This  is  done  through  referencing  the  mix  through  different  playback  systems  in  different  listening  environments  and  adjusting  the  mix  so  that  it  sounds  good  through  as  many  different  playbacks  systems  as  possible  (Sandler,  et  al,  2014,  pp.4-­‐13).    

3.2.4  -­‐  Digital  Mix.    Although  the  techniques  explained  above  were  used  when  performing  the  mix,  there  are  certain  elements  of  the  mixing  process  that  could  be  performed  within  the  DAW  that  could  not  be  performed  during  the  analogue  mix.      During  the  early  stages  of  music  production  all  the  sounds  were  recorded  to  analogue  tape  and  had  to  be  spliced  to  produce  the  final  structured  piece.    It  is  now  much  simpler  to  create  a  complex  structured  track  within  a  DAW  and  respected  musicians’  such  as  Paul  White  (1996)  believe  that  a  track  containing  “out-­‐of-­‐time  and  out-­‐of-­‐tune  playing  can  be  improved  if  you  have  patience”  (White,  1996)  during  the  mixing  process.                One  benefit  of  using  a  DAW  is  the  ability  to  automate  the  parameters  of  almost  every  control  within  the  DAW.    This  was  useful  for  automating  the  volume  controls  of  the  virtual  mixer  within  ‘Logic’.    This  is  a  form  of  dynamic  control  and  allowed  the  volume  of  the  ‘keys’  sample  and  synths  to  be  altered  throughout  the  track  creating  space  and  interesting  dynamics.    The  ability  to  save  the  project  with  all  its  settings  was  beneficial  during  the  digital  mix  and  allowed  the  workload  to  be  spread  out  across  several  sessions  allowing  breaks  to  be  taken  to  rest  the  ears  and  minimise  ear  fatigue  which  can  change  the  way  a  mix  sounds  when  finished  (Robjohns,  2002).                      The  ability  to  return  to  the  processors  and  adjust  settings  was  a  simple  case  of  opening  the  plugin  and  adjusting  the  parameters,  and  unlike  analogue  processors  did  not  require  the  re-­‐recording  of  the  track  each  time  an  adjustment  was  made.      

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3.2.5  -­‐  Analogue  Mix.    While  performing  the  analogue  mix  it  became  obvious  that  while  the  theories  behind  the  mixing  process  were  the  same,  the  process  required  a  lot  more  concentration  and  thought.          Assistance  with  the  process  proved  key  to  performing  the  mix.    While  the  fader  movements  could  be  recorded  they  could  not  be  automated  and  had  to  be  performed  manually  with  accuracy  and  took  several  practices  to  get  right.        There  were  also  limitations  to  the  amount  of  processing  that  could  take  place  simultaneously.              Compression  was  performed  using  the  TL  Audio  ‘Ivory  2  5051’  mono  compressor  and  required  each  track  that  needed  compression  to  be  sent  through  the  desk,  through  the  compressor  and  re-­‐recorded  back  into  the  DAW  to  draw  attention  to  certain  elements  (Sterne,  2006,  pp.338-­‐348).              This  was  repeated  for  the  EQ  applied  on  the  desk  and  fader  levels  were  performed  in  groups.          These  groups  were  then  sent  back  to  the  desk  were  the  final  mix  was  performed.    However,  as  the  mix  continued  it  was  felt  that  some  sounds  needed  adjusting  which  required  the  process  to  be  repeated  several  times  to  acquire  the  desired  outcome.    This  proved  time  consuming  and  required  several  sessions  to  be  performed.        As  the  desk  was  analogue  (see  ‘Appendices  8.2’),  the  settings  on  the  desk  could  not  be  saved  and  notes  of  the  settings  were  written  down  for  future  reference.          This  proved  helpful  when  returning  to  the  studio  for  subsequent  sessions.    However,  even  though  the  position  of  the  parameters  were  noted  down,  it  appeared  that  when  the  settings  were  reapplied  the  effect  produced  on  the  sound  slightly  differed  to  before  and  adjustments  were  needed  to  achieve  the  desired  outcome.    This  wasn’t  a  problem  and  simply  required  some  critical  listening  to  assess  the  quality  of  the  processing  applied  (Hoeg,  et  al,  1997).    

3.3  -­‐  Performing  the  Master.    “Mastering  is  the  last  creative  step  in  the  audio  production  process”  (Katz,  2007,  

p.12)    Usually  combining  the  use  of  EQ  and  dynamic  processors,  mastering  is  the  final  processing  stage  and  is  the  last  step  to  enhance  the  track  before  distribution  (Strurmel,  et  al,  2012,  pp.2-­‐10).          The  aim  of  mastering  is  to  allow  processing  to  take  place  that  not  only  addresses  technical  flaws  such  as  pops,  clicks  and  hum,  but  also  enhance  the  final  mix  helping  achieve  the  artists’  creative  vision  and  consistency  over  different  playback  systems.    EQ  used  at  this  stage  is  not  just  aesthetic,  and  is  often  used  to  remove  unwanted  frequencies  that  are  not  fundamental  to  the  overall  track.    As  EQ  used  during  mastering  is  usually  performed  on  the  entire  track,  it  is  important  to  use  

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processors  that  are  not  just  efficient  but  as  transparent  as  possible  (Mimilakis,  et  al,  2013,  pp.1-­‐7)  as  using  EQ  over  an  entire  mix  means  that  “changing  anything  affects  everything”  (Katz,  2007,  p.103).    However,  Bob  Katz  (2007,  p.215)  believes  that  there  is  no  such  thing  as  a  completely  transparent  audio  processor  and  that  some  mastering  processors  are  used  because  of  what  they  add  to  the  signal.          Two  common  EQs  used  by  mastering  engineers’  are  the  Weiss  ‘EQ1-­‐LP’  and  Manley’s  ‘Massive  Passive  Stereo  Equalizer’.    The  Weiss  is  a  digital  outboard  EQ  that  is  fairly  transparent  with  superb  sound  qualities,  while  the  Manley  tube  EQ  has  ‘just  the  right  amount  of  tube  distortion’  (Katz,  2007,  p.152).    This  suggests  that  there  is  not  one  single  EQ  perfect  for  the  job  of  mastering  as  different  processors  may  affect  different  pieces  of  music  differently.    Compression  used  during  mastering  should  be  used  subtly  and  to  simply  reduce  peak  levels  of  the  audio.    This  is  due  to  the  compression  been  added  over  the  entire  track  and  not  individual  instruments.    This  means  using  hard  compression  settings  are  more  audible  to  the  listener  resulting  in  an  unnatural  sound  that  pumps  when  the  compressor  is  working.    Adjusting  the  attack,  release  and  knee  controls  of  the  compressor  to  softer  settings  allows  a  more  pleasant  result  that  is  more  spacious  allowing  the  listener  to  identify  individual  instruments  (Hjortkjaer  &  Walter-­‐Hansen,  2014,  pp.37-­‐41).              It  is  also  important  to  pay  attention  to  the  tonal  balance  of  the  track  when  using  compression  as  some  compressors  “affect  lower  frequencies  more  than  higher  ones,  shifting  the  tonal  balance  of  the  track”  (Senior,  2009).    This  can  have  an  unwanted  affect  changing  the  whole  balance  of  the  track  essentially  destroying  the  mix  performed  by  the  mix  engineer.            The  final  stage  mastering  processing  usually  involves  brick  wall  limiting.    This  is  a  form  of  dynamic  range  compression  that  not  only  reduces  the  peaks  above  the  threshold  setting,  but  completely  cuts  them  off  allowing  the  signal  to  be  turned  up  without  clipping.    This  process  while  being  a  great  way  of  achieving  ‘loudness’  without  clipping,  significantly  reduces  the  dynamic  range  of  the  audio  and  can  be  fatiguing  to  the  ears  due  to  the  constant  high  level  of  audio  (Vickers,  2010,  pp.1-­‐27).        The  ‘loudness  war’  has  seen  the  on  going  increase  in  the  ‘loudness’  of  recorded  music  over  recent  years.    Although  many  people  believe  that  this  is  due  to  the  competitiveness  of  the  music  industry  with  artists’  wanting  their  music  to  be  louder  than  their  competitors’  (Holmes,  2013,  p.27).    This  may  be  due  to  the  way  in  which  people  listen  to  music.              With  more  people  now  listening  to  music  through  headphones  and  portable  speaker  systems  in  noisy  environments.    Engineers’  apply  heavy  compression  and  limiting  to  try  and  increase  the  ‘loudness’  of  their  music  allowing  their  music  to  be  heard  consistently  over  external  noise  sources  (Vickers,  2010,  pp.1-­‐27).          While  studies  have  shown  this  to  be  true,  end  users  have  no  control  over  the  amount  of  dynamics  processing  applied  to  a  track,  but  they  do  have  the  use  of  the  volume  control  on  their  chosen  playback  system.    This  allows  the  user  to  increase  the  playback  level  allowing  the  mastering  engineer  to  apply  less  

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dynamic  processing  preserving  the  dynamic  range  and  creative  vision  of  the  artist  (Sturmel,  et  al,  2012,  pp.2-­‐10).          This,  however  raises  another  issue,  at  what  level  will  the  music  be  played  back?    As  the  mastering  engineer  has  no  control  over  the  listening  level  that  the  music  is  played  back,  the  mastering  engineer  must  ensure  that  the  amount  of  processing  applied  will  translate  well  through  as  many  playback  systems  as  possible.    This  can  be  done  through  referencing  the  track  through  different  playback  systems  in  different  listening  environments  that  replicate  common  listening  methods.    This  can  also  help  keep  the  dynamics  of  the  track  in  perspective  to  a  track  that  is  known  to  be  popular  with  listeners’  of  the  genre  (Johnston  &  Spors,  2012,  pp.105-­‐106).    It  is  suggested  that  calibrating  the  monitors  to  a  level  of  83dB  allows  sufficient  dynamic  range  reproduction  on  most  systems  and  allows  the  engineer  to  have  a  reference  level  for  monitoring  purposes  (Mimilakis,  et  al,  2013,  pp.1-­‐7).    The  ‘K-­‐System’  developed  by  Bob  Katz  allows  three  settings  for  calibrating  systems  by  using  three  test  signals  known  as  ‘K20’,  ‘K14’  and  ‘K12’.    By  deciding  which  system  the  reference  track  came  under  by  using  the  integrated  ‘K-­‐system’  within  the  Voxengo  ‘SPAN’  plugin.    The  playback  system  was  calibrated  to  the  ‘K20’.    This  allowed  the  mastering  process  to  be  as  efficient  as  possible  using  a  reference  track  as  a  guide  to  the  dynamics,  tonal  balance  and  perceived  ‘loudness’  of  the  track.      As  the  track  will  be  written  to  a  compact  disc  (CD)  the  file  was  exported  as  a  16Bit  44.1kHz  WAVE  stereo  file  adhering  to  the  ‘Red  Book’  standard  devised  by  Philips  and  Sony  (1980).    In  the  commercial  environment  mastering  is  also  the  stage  that  prepares  the  track  for  distribution  and  can  include  priority  queuing  (PQ),  adding  CD  text  and  the  international  standard  recording  code  (ISRC)  allowing  each  track  to  be  identified  allowing  ownership  to  be  traced.    However,  as  this  project  is  focusing  on  the  signal  processing  methods  used  during  these  stages,  these  stages  will  not  be  considered  or  performed.    

3.3.1  -­‐  Digital  Master.    Using  the  processors  provided  with  ‘Logic’,  mastering  was  fairly  simple  and  required  several  small  sessions  to  be  completed,  each  time  referencing  the  track  through  different  playback  systems  in  different  environments.    The  ability  to  change  processors  and  settings  with  a  few  mouse  clicks  as  well  as  saving  the  project  meant  that  once  flaws  were  heard  during  referencing  it  was  a  simple  case  of  opening  the  project  and  adjusting  the  settings.    

3.3.2  -­‐  Analogue  Master.    Performing  the  analogue  master  required  more  time  and  concentration.    Having  not  used  the  environment  and  system  used  for  the  process  (room  E2  at  Staffordshire  University).    It  took  several  sessions  to  achieve  a  master  that  was  

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adequate.    The  equipment  used  seemed  fairly  transparent  and  for  the  first  few  sessions  were  overused  resulting  in  overly  heavy  EQ  and  compression  causing  a  final  product  that  lacked  dynamics  and  was  biased  towards  the  higher  frequencies.    After  several  sessions  with  more  experience  of  the  equipment  and  the  environment  the  settings  were  adjusted  and  the  final  product  had  a  similar  tonal  balance  to  the  chosen  reference  track.    The  equipment  used  during  both  the  digital  and  analogue  mixing  and  mastering  

process  can  be  found  in  ‘Appendices  8.2’.      

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4  -­‐  Testing  Methodology              

 Producing  conclusive  results  that  are  able  to  provide  artists’  with  a  definitive  answer  as  to  when  and  at  what  stage  the  different  technologies  are  best  used  will  be  the  key  to  it’s  success.              However,  as  music  and  it’s  sonic  qualities  are  a  matter  of  personal  preference  and  rely  more  upon  the  personality  and  social  experiences  of  the  listener  (Swami,  et  al,  2013,  pp.377-­‐383).    The  test  should  be  performed  on  subjects’  chosen  at  random.    This  will  help  ensure  that  the  data  collected  will  be  a  reflection  of  the  general  public  and  not  a  targeted  cultural  sector  of  the  public  (Pickering,  2008,  p.19).              This  will  allow  the  conclusions  made  to  help  the  artists’  future  decisions  about  signal  processing  to  appeal  to  a  wider  sector  of  the  public.    

4.1  -­‐  Research.    The  listening  test  produced  will  be  based  on  several  research  methods  to  ensure  that  the  data  collected  will  provide  the  artist  with  as  much  information  as  possible.    

4.1.1  -­‐  ‘ABX’  Testing.    The  ‘ABX’  testing  method  is  designed  to  “provide  a  simple,  intuitive  means  to  determine  if  there  is  an  audible  difference  between  two  audio  signals”  (Boley  &  Letser,  2009,  p.1).    It  relies  on  the  listener  detecting  the  differences  between  two  audio  signals  played  through  a  piece  of  equipment  such  as  the  ‘ABX  Comparator’  produced  by  ‘QSC  Audio’  (1980).    The  advantage  of  this  method  is  that  the  test  can  be  carried  out  using  an  automatic  switcher  allowing  the  audio  played  to  alternate  between  two  signals  without  interference  by  the  research  conductor.    This  helps  remove  unconscious  bias  on  the  test  subject  by  the  research  conductor  (QSC  Audio,  1998,  p.3).            This  method  could  be  used  to  incorporate  several  pieces  of  audio  producing  statistical  results  revealing  which  piece  of  audio  that  the  subjects’  prefer.          However,  as  the  results  of  this  testing  method  will  produce  simple  statistics,  it  will  not  provide  information  as  to  why  they  prefer  the  piece.    The  results  will  be  rather  vague  and  will  not  provide  artists’  with  informative  feedback  that  could  be  helpful  for  future  productions.    

4.1.2  -­‐  Qualitative  Research.    While  ‘ABX’  testing  alone  doesn’t  allow  for  information  to  be  gathered  concerning  the  reasons  for  the  listeners’  choices.    Qualitative  research  methods  will  allow  a  more  informed  answer  to  be  provided  by  the  test  subjects’  by  providing  questionnaires  and  unstructured  interviews  to  allow  more  in-­‐depth  

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answers  to  be  obtained  allowing  more  informative  conclusions  to  be  made  that  are  able  to  explain  why  the  piece  of  music  appeals  to  the  listener  (McLeod,  2008).        This  will  be  time  consuming  and  require  a  written  survey  to  be  produced  that  can  allow  answers  related  to  the  sample  clips  to  be  collated  and  analysed.    This  will  provide  personal  preference  as  to  which  clip  is  preferred  to  be  recorded  and  analysed.        

4.1.3  -­‐  Quantitative  Research.    As  the  results  of  the  listening  test  will  be  based  on  a  number  of  subjects’  opinions,  it  is  important  that  the  results  can  be  measured.        Quantitative  research  relies  on  gathering  data  in  numerical  form  that  can  be  categorised  allowing  the  results  to  be  measured  (McLeod,  2008).    This  method  allows  the  results  of  simple  ‘yes/no’  answers  or  rating  systems  to  be  collated  into  a  table  or  graph  that  can  show  the  most  and  least  popular  choices  of  the  survey.              This  method  relies  on  the  involvement  of  as  many  subjects’  as  possible  from  as  many  cultural  backgrounds  as  possible  to  form  conclusions  based  on  numerical  data.            While  this  testing  method  allows  the  analysis  of  simple  numerical  data  to  be  performed.    The  results,  like  the  ‘ABX’  testing  method,  will  not  provide  information  as  to  why  the  test  subjects’  decisions  were  made.    This  will  result  in  an  uninformative  conclusion  that  will  not  provide  enough  information  to  inform  artists’  on  their  future  productions.              

4.2  -­‐  Chosen  Testing  Method.    As  the  advantages  and  disadvantages  of  several  testing  methods  have  now  been  assessed,  the  testing  method  for  this  investigation  can  now  be  made  with  consideration  of  the  research  conducted.    It  is  suggested  that  the  most  effective  testing  method  for  any  research  is  to  incorporate  several  testing  methods  to  produce  a  hybrid  method  that  can  provide  as  much  accurate  information  as  possible  that  is  based  on  the  material  being  tested  and  the  aim  of  the  investigation  (Silverman,  2008,  p.8).    

4.2.1  -­‐  Producing  the  Listening  Test.    Utilising  the  ‘ABX’  testing  method  that  helps  provide  a  test  unbiased  by  the  conductor  or  outside  influence  will  help  provide  results  based  on  the  opinions  of  the  test  subjects’  perceptions  of  the  audio  alone.    This  will  provide  the  best  method  for  a  listening  test  as  “the  only  sufficient  method  of  assessing  the  quality  of  audio  is  by  listening”  (Hoeg,  et  al,  1997,  p.40).  

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This  method  will  be  implemented  by  selecting  the  same  small  section  of  audio  from  each  version  and  playing  it  to  the  test  subjects’  without  informing  them  of  which  version  they  are  listening  to.    This  will  allow  blind  testing  to  take  place  that  is  unaffected  by  having  previous  knowledge  of  how  the  audio  was  processed.              This  helps  produce  unbiased  results,  as  if  the  test  subject  has  prior  knowledge  of  which  processing  method  was  used.    They  may  be  inclined  to  make  their  decisions  based  on  their  own  personal  opinion  of  the  processing  method  used,  and  not  on  how  the  audio  clips  appeal  to  them  through  listening  alone.    This  will  be  performed  by  loading  the  audio  clips  into  a  ‘Logic’  project  and  soloing  one  clip,  playing  it  for  the  listener  and  repeating  this  process  for  the  rest  of  the  sample  clips.              The  clips  will  be  played  in  random  order  to  minimise  the  effects  of  listening  fatigue  and  a  bias  towards  the  first  or  last  sample  been  played  (Vickers,  2010,  pp.1-­‐27).    The  order  in  which  the  clips  are  played  will  be  noted  down  for  use  when  collating  the  data  and  the  test  subject  will  not  be  made  aware  of  the  playing  order.    This  will  allow  the  test  subject  to  listen  to  the  audio  clips  and  answer  the  survey  questions  referring  to  the  order  that  they  heard  them.    Recording  the  order  in  which  the  test  subject  heard  the  clips  along  with  what  number  the  test  subject  has  given  will  allow  the  data  collected  to  be  broken  down  into  statistical  information  that  will  show  the  outcome  of  the  most  and  least  preferred  clips.    Care  will  be  taken  to  not  bias  the  subjects’  in  any  way.    This  will  include  minimal  eye  contact,  no  discussion  as  the  ‘Front  Sheet’  provided  will  cover  the  information  needed  for  the  subjects’,  and  not  facing  the  subjects’  during  the  test  to  minimise  influence  of  the  researcher  over  the  test  subjects’.    Each  track,  while  been  processed  separately  will  all  peak  at  0dBFS.    This  will  allow  a  certain  amount  of  consistency  through  all  four  clips  (Vickers,  2010,  pp.1-­‐27).    However,  this  will  not  allow  for  the  difference  of  the  dynamics  of  each  clip,  but  as  each  clip  has  been  produced  using  the  same  reference  track  and  monitored  to  ensure  that  each  version  has  the  same  average  level  using  the  Voxengo  ‘SPAN’  plugin  using  the  ‘K20’  setting,  the  overall  perceived  ‘loudness’  should  be  consistent  through  all  clips.          The  playback  volume  of  the  test  should  be  consistent  for  all  test  subjects’  and  will  be  measured  using  the  average  rating  of  83dB  using  a  sound  pressure  level  (SPL)  meter.    The  volume  level  of  the  internal  soundcard  (Apple  ‘MacBook  Pro’)  will  be  noted  and  remain  static  through  all  listening  tests  performed.    This  calibration  stage  will  be  introduced  in  order  to  prevent  the  biasing  effect  of  difference  in  perceived  ‘loudness’  (Mimilakis,  et  al,  2013,  pp.1-­‐7).    As  the  aim  of  the  test  is  to  collect  the  opinions  of  the  general  public,  the  environment  in  which  the  subjects’  will  be  tested  may  vary.    While  a  quiet  studio  environment  with  an  accurate  playback  system  and  as  little  outside  noise  as  possible  would  be  ideal.    Practically  this  will  be  difficult  to  execute  and  will  not  replicate  the  natural  listening  environment  of  the  general  public.      

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       Recent  years  have  seen  the  shift  towards  mobile  listening  devices  and  an  increasing  number  of  people  are  now  listening  to  the  majority  of  their  music  through  headphones  (Johnston  &  Spors,  2012,  pp.105-­‐106).    For  this  reason  headphones  will  be  used  during  the  listening  tests.    This  method  will  help  replicate  the  natural  listening  environment  of  the  general  public  according  to  Johnston  and  Spors  (2012),  and  also  help  minimise  outside  noise  that  has  the  ability  corrupt  any  listening  test.    While  this  method  will  be  quite  time  consuming,  AES  member  Linkwitz  (2009)  believes  that  listening  to  music  through  headphones  is  equivalent  to  listening  to  studio  monitors  in  a  near  anechoic  environment  allowing  for  critical  listening  to  take  place.          This  will  aid  the  results  of  the  evaluation  and  reduce  the  effects  that  the  environment  can  have  on  the  listener.    The  amount  and  position  of  people  in  a  room  along  with  the  equipment  and  surfaces  will  affect  the  reflections  and  direct  sound  heard  by  the  listener  (Lockwood,  White  &  Robjohns,  2013,  p.217).    This  will  affect  the  stereo  image,  frequency  intensity  and  tonal  balance  of  the  track  heard,  all  of  which  will  be  minimised  by  listening  to  the  clips  through  headphones  (Linkwitz,  2009,  pp.1-­‐11).    The  headphones  used  will  be  KRK  ‘KNS-­‐8400’  studio  monitoring  headphones  (see  ‘Appendices  8.2’).    Produced  by  a  company  who  are  well  established  in  the  world  of  studio  monitors.    They  are  designed  to  “reproduce  the  experience  of  listening  on  studio  monitors  as  closely  as  possible”  (Inglis,  2011).    One  criticism  that  is  made  about  the  headphones  is  that  they  are  described  as  being  fatiguing  when  listening  for  long  periods  of  time.    This  should  not  affect  the  outcome  of  the  listening  tests  as  the  total  listening  time  for  the  test  will  be  under  three  minutes.    This  will  also  ensure  that  the  listening  environment  for  each  test  subject  is  consistent  and  unbiased  by  the  characteristics  of  different  playback  systems  as  described  by  Breshears  (2001).    

4.2.2  -­‐  Producing  the  Survey.    “It  is  not  possible  to  develop  a  questionnaire  that  can  be  analysed  properly  unless  

you  first  understand  methods  of  analysis”  (Vaus,  2002,  p.94).    

The  information  needed  for  this  investigation  to  be  successful  relies  on  statistical  data  that  can  show  which  version  people  least  and  most  prefer,  along  with  information  for  why  people  prefer  the  version  they  choose.    This  will  allow  reasoning  as  to  why  the  most  popular  version  is  preferred  based  on  data  analysis  and  research.      The  survey  requires  a  combination  of  quantitative  and  qualitative  research  methods  to  quire  sufficient  information  that  will  aid  the  objective  of  the  project  (Sale,  et  al,  2002,  pp.43-­‐53).              Quantitative  data  will  provide  statistical  information  that  can  be  analysed  and  shown  as  numerical  information  that  will  indicate  which  processing  method  the  

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test  subjects’  prefer.    “The  goal  is  to  measure  and  analyse  casual  relationships  between  variables  within  a  value-­‐free  framework”  (Sale,  et  al,  2002,  pp.43-­‐53).        It  is  important  that  the  information  gained  from  the  subjects’  is  free  from  influence  by  the  investigator.    This  requires  the  questions  asked  to  not  ‘lead’  the  subject  in  any  way  as  this  would  taint  the  results  leading  to  conclusions  been  made  that  do  not  represent  the  thoughts  and  feelings  of  the  general  public.    This  requires  that  the  investigator  remains  separate  from  the  subject  during  the  completion  of  the  survey  (Johnson  &  Onwuegbuzie,  2004,  pp.14-­‐26).    This  will  be  implemented  by  leaving  the  room  while  the  subject  completes  the  survey  so  that  no  discussion,  eye  contact  or  emotional  response  can  be  made  between  the  subject  and  investigator.    This  should  ensure  that  no  bias  is  made  towards  any  one  part  of  the  listening  test  and  survey.              This  hypothesis  may  be  hindered  by  the  presence  of  the  investigator  during  the  listening  test,  but  can  be  combatted  by  having  minimal  engagement  with  the  subject  and  insisting  that  the  subject  faces  away  from  the  investigator  during  the  test.    The  questions  that  will  be  included  in  the  survey  should  anticipate  what  information  is  needed  from  the  subjects’  to  ensure  that  the  data  collected  is  able  to  provide  definitive  answers  to  the  aims  of  the  project  (Vaus,  2002,  p.94).                The  questions  chosen  for  this  investigation  are  as  follows:    

• Gender?  • Age?    • Which  version  do  you  prefer  most?  • Pick  four  words  from  the  selection  provided  below  that  best  describe  

why  you  prefer  the  version  that  you  selected  in  the  previous  question.  • Which  version  do  you  least  prefer?  • Pick  four  words  from  the  selection  provided  below  that  best  describe  

why  you  least  prefer  the  version  that  you  selected  in  the  previous  question.  

 The  questions  chosen  for  the  survey  were  constructed  to  ensure  that  the  information  collected  is  based  solely  on  the  subjects’  personal  preference  and  are  not  designed  to  ‘lead’  the  subject  by  introducing  bias  towards  any  one  version.    Not  providing  a  rating  scale  for  each  version  allows  the  statistical  data  collected  to  provide  answers  as  to  which  processing  method  is  preferred  based  on  listening  alone.    Choosing  descriptive  words  that  can  describe  the  sonic  qualities  of  a  piece  of  music  is  difficult,  often  vague  and  varies  from  person  to  person.    Often  referring  to  the  frequency  content  of  instruments,  descriptive  words  can  describe  the  tonal  balance  of  an  instrument.    Mixing  engineer  and  lecturer  Roey  Izhaki  (2008)  shows  this  in  the  form  of  a  table:  

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 However,  these  descriptions  are  associated  with  the  frequency  content  of  individual  instruments  and  not  an  entire  track.    Contrary  to  Izhaki’s  method,  composer  Paul  Nelson  (2005)  has  devised  a  table  of  positive  and  negative  descriptive  words  that  was  “originally  intended  for  non-­‐musicians  who  need  to  communicate  with  music  professionals”  (Nelson,  2005)  and  are  as  follows:    

Negative   Positive  Dark   Bright  Muddy   Clean  Cold   Warm  Harsh   Smooth  

 These  provide  a  means  for  the  test  subjects’  to  describe  why  they  prefer  the  tracks  they  choose.    However,  as  there  is  no  standardized  format  for  descriptive  words  for  music  (Izhaki,  2008,  p.231).    The  positive  and  negative  connotations  of  these  words  could  vary  from  person  to  person  and  as  such  will  be  grouped  together  without  any  connotations  made  towards  there  meanings.    This  will  allow  a  relationship  between  the  statistical  and  descriptive  data  to  be  made  that  may  help  the  conclusion  of  the  analysis  carried  out.    

Figure  1.1  -­‐  Table  showing  some  descriptive  words  for  musical  instruments  (Izhaki,  2008,  p.232).  

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5  -­‐  Results                    

 With  the  listening  test  and  surveys  completed,  analysis  of  the  data  collected  can  now  be  performed.    For  the  purpose  of  the  survey  the  four  different  signal  processing  methods  were  referred  to  as  ‘Versions’  to  not  lead  the  subject.        The  following  is  a  description  of  each  version:    

• Version  1  –  Digital  Mix/Digital  Master  • Version  2  –  Digital  Mix/Analogue  Master  • Version  3  –  Analogue  Mix/Analogue  Master  • Version  4  –  Analogue  Mix/Digital  Master    

 

5.1  -­‐  Analysis  of  the  Data  Collected.    From  the  initial  analysis  of  the  data  the  graph  below  shows  the  versions  most  preferred  and  least  preferred  by  the  test  subjects’.    

 

Figure  2.1  –  Graph  showing  the  versions  that  are  most  and  least  preferred  by  the  test  subjects’.  

 This  shows  that  38%  of  the  subjects’  preferred  version  1  and  38%  of  the  subjects’  least  preferred  version  3.    When  compared  to  the  32%  of  subjects’  who  preferred  version  2,  and  the  16%  and  14%  of  subjects’  who  preferred  versions  3  

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and  4.    It  shows  that  the  digital  signal  processing  method  is  the  most  preferred  method  for  processing  audio  according  to  the  subjects’  tested.      This  could  be  due  to  the  way  in  which  the  test  was  administered.    As  each  subject  will  have  differently  shaped  ears  that  will  affect  the  sound  leakage  of  the  headphones  on  the  subjects’.    This  suggests  that  what  the  subjects’  hear  “is  a  summation  of  the  sound  transmitted  through  the  headset,  leaked  sound,  and  tissue  conducted  sound”  (Riikonen,  et  al,  2008,  pp.1-­‐8).    This  means  that  the  sound  heard  by  each  test  subject  will  be  slightly  different,  and  could  affect  the  data  collected.    

 Figure  2.2  –  Graph  showing  the  age  range  and  gender  of  subjects’  that  choose  versions  1  and  3.  

 The  age  group  and  gender  of  the  subjects’  that  choose  versions  1  and  3  also  show  that  the  majority  of  these  choices  are  made  by  people  between  the  ages  of  16-­‐35  and  are  male.    However  from  all  the  subjects’  tested  66%  were  male  which  shows  the  gender  of  test  subjects’  who  selected  both  versions  1  and  3  are  more  equal  than  they  appear  in  the  data.    An  important  factor  to  remember  from  these  results  is  the  age  group.    As  research  shows,  the  perceived  intensity  of  higher  frequencies  reduces  with  age  (Munro,  et  al,  2013,  pp.1-­‐17).    This  suggests  that  one  possible  reason  why  the  test  subjects’  aged  between  16-­‐35  least  preferred  version  3  is  due  to  an  increased  perception  of  high  frequency  content  resulting  in  version  3  sounding  ‘Harsh’.  

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       However,  with  the  data  showing  that  the  test  subjects’  who  preferred  version  1  describing  the  track  as  ‘Bright’  and  version  3  as  ‘Muddy’  and  ‘Dark’,  the  results  cannot  be  backed  up  by  the  research  conducted  into  age  related  hearing  loss  and  instead  must  be  assumed  to  be  personal  preference.              It  could  mean  that  the  16-­‐35  age  group  who  have  a  better  perception  of  higher  frequencies  prefer  the  higher  frequency  detail  in  version  1  while  the  36-­‐65  age  group  who  have  grown  used  to  not  perceiving  higher  frequencies  with  as  much  intensity  prefer  a  different  tonal  balance  in  music    (Capra,  et  al,  2006,  pp.1-­‐10).    

 Figure  2.3  –  Graph  showing  the  descriptive  words  used  when  describing  both  versions  1  and  3.  

 The  qualitative  data  collected  from  the  descriptive  words  provided  show  that  although  the  descriptive  words  were  not  labelled  as  positive  and  negative,  the  majority  of  subjects’  did  choose  the  positive  descriptive  words  for  the  version  they  most  preferred  and  the  negative  descriptive  words  for  the  version  that  they  least  preferred.              While  the  data  collected  correlates  with  the  connotations  of  the  descriptive  words,  several  people  also  choose  to  describe  the  version  they  most  preferred  with  the  negative  descriptive  words.    This  shows  that  the  words  people  use  to  describe  music  vary  and  is  a  case  of  personal  preference  and  shows  that  there  is  no  standard.    Descriptive  words  have  different  meanings  to  different  people  and  could  possibly  be  decided  upon  through  cultural  backgrounds  and  social  standings  (Swami,  et  al,  2013,  pp.377-­‐383),  which  could  provide  a  reason  for  the  data  collected.    

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5.2  -­‐  Conclusion.    While  the  data  shows  evidence  that  more  people  preferred  the  digital  mixing  and  mastering  method,  it  does  not  provide  a  wide  enough  spectrum  of  test  subjects’  to  conclusively  show  that  the  majority  of  the  general  public  prefer  this  method.    This  is  due  to  the  fact  that  the  listening  test  and  survey  was  only  carried  out  on  50  test  subjects’  due  to  the  controls  that  had  to  be  in  place  to  ensure  a  fair  experiment.    50  test  subjects  of  whom  the  majority  were  male  and  aged  between  16-­‐35  biases  the  evidence  towards  a  specific  cultural  sector.    However,  according  to  a  Nielsen  report  (2011)  the  largest  sector  of  people  who  purchase  music  (at  22%)  are  aged  between  25-­‐29  (Peoples,  2011).    So  although  the  survey  is  seemingly  biased  towards  a  certain  group,  it  does  represent  the  largest  sector  of  music  consumers’.    During  the  processing  methods  performed  it  became  obvious  that  using  DSPs  provided  more  flexibility  and  allowed  more  processing  to  be  added  easily.    While  during  the  analogue  processing  each  signal  had  to  be  processed  separately  and  re-­‐recorded  resulting  in  only  one  EQ  and  one  compression  stage  being  used,  the  digital  method  allowed  several  EQs  and  compressors  to  be  added  at  the  touch  of  a  button.    This  allowed  more  effective  negative  EQ  techniques  to  be  used  by  using  several  EQs  to  remove  unwanted  frequencies  to  a  greater  effect  than  when  removing  frequencies  during  analogue  processing  (Morrell  &  Reiss,  2009,  pp.1-­‐20).    Although  the  tracks  could  have  been  processed  several  times  through  the  analogue  EQ,  time  constraints  left  less  time  for  the  processing  to  be  performed.    This  corresponds  to  the  qualitative  data  collected  with  subjects’  feeling  that  version  1  sounded  ‘cleaner’  and  ‘smoother’  than  version  3  (Perez-­‐Gonzalez  &  Reiss,  2009,  pp.1-­‐7).        Although  there  is  widespread  belief  that  the  increasing  use  of  compression  on  music  is  deteriorating  the  sound  quality  of  music  (Hjortkjaer  &  Walter-­‐Hansen,  2014,  pp.37-­‐41).    The  evidence  form  the  data  collected  showing  version  1  to  be  the  most  preferred  version  suggests  that  this  isn’t  the  case.    As  version  1  had  more  dynamic  range  compression  added  to  individual  tracks  and  over  the  entire  mix,  due  to  the  ease  of  simply  adding  a  compressor  at  the  touch  of  a  button.    It  suggests  that  the  amount  of  compression  added  to  a  piece  of  music  does  not  deteriorate  music’s  sonic  qualities.    This  is  also  supported  by  tests  carried  out  by  Hjortkjaer  and  Walter-­‐Hansen  (2014)  where  they  performed  listening  tests  using  several  tracks  that  had  been  re-­‐mastered.    By  playing  the  original  mastered  tracks  and  the  re-­‐mastered  track  to  test  subjects’  the  results  showed  that  there  was  “no  evidence  of  preference  for  the  less  compressed  music”  (Hjortkjaer  &  Walter-­‐Hansen,  2014,  pp.37-­‐41).            Another  reason  why  the  results  have  turned  out  the  way  they  did  may  be  due  to  the  environments  in  which  they  were  performed.    While  version  1  was  processed  in  a  familiar  environment  using  familiar  equipment,  version  3  was  produced  in  an  unfamiliar  environment  on  equipment  that  the  candidate  had  very  little  experience  of.    This  may  result  in  over  or  under  processing  sounds  due  to  the  lack  of  experience  of  the  listening  environment  and  its  characteristics  (Linkwitz,  2009,  pp.1-­‐11).    This  could  have  been  overcome  by  spending  more  time  using  the  

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equipment  in  the  environment  or  using  the  analogue  equipment  in  the  same  environment  as  the  one  in  which  the  DSP  was  performed.    This  would  eliminate  variations  in  room  characteristics  and  provide  a  more  even  platform  for  the  processing  to  be  performed.    Although  the  way  in  which  the  test  was  administered  may  have  affected  the  outcome  of  the  test,  through  biasing  frequencies  through  the  headphones  used  and  listening  in  the  unnatural  environment  of  headphones,  which  according  to  Linkwitz  (2009)  replicates  a  near  anechoic  environment  for  the  listener  from  reducing  natural  reflections.    The  test  was  administered  in  the  same  way  for  each  test  subject,  so  although  external  noise  may  have  differed,  the  frequency  balance  of  the  playback  system  remained  the  same  and  it  does  replicate  the  normal  listening  environment  of  many  music  listeners’  as  there  is  “an  increasing  number  of  individuals  who  use  headphones  when  listening  to  audio”  (Johnston  &  Spors,  2012,  pp.105-­‐106).            However,  perhaps  this  could  have  been  helped  further  by  conducting  the  listening  test  in  a  more  sterile  environment  like  a  studio.    Although  the  test  would  still  be  administered  using  headphones,  the  environment  would  then  remain  the  same  for  each  test  subject,  helping  control  the  test  further.                The  outcome  of  the  test  could  have  also  been  affected  by  the  mood  and  preference  of  the  listener  (Swami,  et  al,  2013,  pp.377-­‐383).    Although  the  test  stated  that  there  should  be  no  consideration  for  whether  the  subject  likes  the  piece  or  not,  as  the  track  was  of  a  certain  genre  it  may  have  affected  the  decisions  made  by  the  test  subjects’.              Different  genres  of  music  tend  to  have  different  traits  such  as  varying  tonal  balance  and  emphasis  on  different  elements  of  a  musical  piece,  and  if  the  test  subject  does  not  have  prior  knowledge  of  these  traits,  they  could  judge  the  piece  on  the  traits  of  the  genre  that  they  personally  prefer  (Vickers,  2010,  pp.1-­‐27).              Future  investigations  should  take  this  into  account  performing  the  experiment  using  several  pieces  of  music  from  different  genres,  or  target  a  genre  specific  audience  for  testing  allowing  experience  to  play  a  part  in  the  results,  although  they  may  still  not  like  the  piece,  they  would  have  a  better  knowledge  of  the  musical  traits  of  the  genre.      Based  on  the  subjects’  tested  the  results  show  that  people  least  prefer  the  analogue  mixing  and  mastering  method.              This  may  be  due  to  the  nature  of  how  analogue  technology  works.    While  been  seen  as  a  more  accurate  method  of  processing  audio  due  to  the  sound  waves  been  replicated  using  voltage  variations  rather  than  having  a  digital  representation  made  with  varying  accuracy  dependant  on  the  bit  depth  and  sample  rate.    Analogue  equipment,  as  discussed  previously,  is  susceptible  to  variations  in  signal  quality  by  outside  interference  as  well  as  the  components  used  within  the  equipment  (Floru,  2005,  pp.1-­‐16).            The  qualitative  data  collected  shows  that  the  test  subjects’  felt  that  version  3  sounded  less  ‘clean’,  ‘muddier’  and  ‘harsher’  than  version  1.    This  may  be  due  to  the  components  of  the  equipment  used  affecting  the  low  frequencies  in  an  

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undesirable  way  resulting  in  an  unbalanced  frequency  spectrum  where  the  high  frequencies  become  more  prominent  resulting  in  a  harsh  sound.          EMI  and  RFI  could  also  have  affected  the  overall  sound  of  the  piece  by  introducing  noise  making  the  piece  sound  muddy  and  undefined  by  adding  unwanted  frequency  content.    This  could  also  have  been  caused  by  inaccurate  representation  of  the  frequency  content  caused  by  printed  circuit  board  (PCB)  effects  such  as,  atmospheric  moisture  absorption,  leakage  in  resistors  and  voltage  drops  in  trace  foils  (Jung,  2005).              Performing  the  processing  again  using  the  same  equipment  may  produce  different  results  due  to  differing  outside  interference  and  varying  equipment  performance.    

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6  -­‐  Evaluation                    

 Based  on  the  data  collected  and  contrary  to  the  popular  belief  that  “digitally  reproduced  music,  is  said  to  sound  sterile,  dry,  or  cold”  (Evens,  2005,  p.30).    The  subjects’  tested  actually  preferred  the  digitally  processed  version.    While  in  the  context  of  this  investigation  the  results  can  be  used  to  produce  a  conclusion,  the  analysis  of  the  data  shows  that  there  are  many  factors  that  could  have  affected  the  outcome  of  the  test.    The  material,  equipment  used,  subjects’  tested  and  techniques  performed  could  all  have  affected  the  results.    While  the  results  are  positive  and  have  fulfilled  the  desired  outcome  of  the  investigation  by  been  able  to  advise  artists’  in  which  signal  processing  technology  to  choose  for  future  productions.    The  many  varying  factors  that  could  affect  the  outcome  of  the  results  suggest  that  further  investigations  are  needed  in  order  to  gain  further  knowledge  into  which  processing  methods  listeners’  prefer.              Different  genres,  specific  targeting  of  test  subjects’,  different  equipment,  different  testing  methods  and  production  techniques  specific  to  the  genre  should  all  be  investigated  further  and  may  provide  a  more  detailed  outcome  for  future  investigations.    Quantitative  and  qualitative  data  collection  as  discussed  previously  relies  on  the  perception  of  the  test  subjects’  and  is  often  formed  by  the  society  and  cultural  surroundings  of  which  they  live  (Sale,  et  al,  2002,  pp.43-­‐53).    Considering  these  further  investigations  should  also  be  performed  on  a  regular  basis  to  take  into  account  the  perceptions  of  a  changing  society.    Carrying  out  the  investigations  on  a  wider  scale  and  specific  subject  targeting  would  also  be  beneficial  but  would  narrow  the  target  audience  of  the  investigation.    With  recent  advancements  in  technology  the  processing  methods  available  to  artists’  have  become  more  complex  and  artists’  who  prefer  tactile  feedback  when  processing  audio,  utilising  more  senses  such  as  muscular  memory,  and  positive  recognition  through  physical  feedback  now  have  more  options  available  (Altinsoy,  et  al,  2010,  pp.1-­‐7).              With  the  introduction  of  DSPs  into  hardware  equipment  that  act  as  an  interface  for  signal  processing  such  as  the  Focusrite  ‘Liquid  Channel’  and  the  Lexicon  ‘MPX’  series.    It  is  now  possible  to  have  the  tactile  feedback  of  an  analogue  unit  with  the  advantages  of  digital  processing  such  as  been  able  to  save  and  recall  settings  as  well  as  emulating  some  of  the  characteristics  of  analogue  circuitry  without  the  sometimes  unpredictability  of  the  components.    However,  should  future  investigations  results  show  that  test  subjects’  prefer  the  sound  of  analogue  circuitry  but  artists’  do  not  have  access  to  such  equipment.    Many  manufacturers’  now  produce  emulations  of  many  analogue  signal  processors  in  the  form  of  DSP  plugins  compatible  with  many  DAWs.    This  allows  artists’  to  recreate  the  sound  characteristics  of  analogue  processors  at  the  touch  

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of  a  button  with  the  added  advantage  of  been  able  to  save  and  recall  settings  as  well  as  using  several  instances  of  the  same  plugin  simultaneously.    The  ‘Raven  MTX’  created  by  Steven  Slate  of  ‘Slate  Pro  Audio’  is  a  touchscreen  controller  compatible  with  Avid’s  ‘Pro  Tools’  and  Apple’s  ‘Logic  Pro’  and  bridges  the  gap  between  analogue  and  digital  platforms  allowing  the  user  the  advantages  of  digital  processors  and  the  working  methods  of  analogue  setups  with  it’s  touchscreen  technology  (Robjohns,  2013,  p.27).    Further  investigations  using  both  DSP/analogue  hybrid  hardware  equipment  as  well  as  analogue  circuitry  emulating  DSP  plugins  may  produce  results  that  contradict  this  investigation  ultimately  leaving  the  signal  processing  decisions  up  to  the  artists’  personal  preference.    

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7  -­‐  Bibliography                  

 Altinsoy,  E.,  et  al.    (2010).    ‘Tactile  Music  Instrument  Recognition  for  Audio  Mixers.’    In:    Audio  Engineering  Society  Convention  Paper  8142  Presented  at  the  128th  Convention,  May  22-­‐25,  2010.    London,  UK.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐7.    Bennett,  S.    (2005).    ‘Stem  Mixing  in  Logic’.    Available:    http://www.soundonsound.com/sos/oct05/articles/logictech.htm.    Last  accessed  11/03/14.    Boley,  J.,  Lester,  M.    (2009).    ‘Statistical  Analysis  of  ABX  Results  Using  Signal  Detection  Theory.’    In:    Audio  Engineering  Society  Convention  Paper  7826  Presented  at  the  127th  Convention.    October  9-­‐12,  2009.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐7.    Brandenburg,  M.,  Kahrs,  K.    (1998).    ‘Applications  of  Digital  Signal  Processing  to  Audio  and  Acoustics’.    Hingham,  MA:    Kluwer  Academic  Publishers.    p.1.    Breshears,  V.    (2001).    ‘Mixing  Techniques  for  Multi-­‐Channel  (Left/Center/Right)  Sound  Reinforcement  Systems.’  In:    Audio  Engineering  Society  Convention  Paper  5486  Presented  at  the  111th  Convention,  September  21-­‐24,  2001.    New  York,  NY.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐7.    Capra,  A.,  et  al.    (2006).    ‘Investigation  of  Hearing  Loss  Influence  on  Music  Perception,  in  Auditoria,  by  means  of  Stereo  Dipole  Reproduction’.    In:    Audio  Engineering  Society  Convention  Paper  6887  Presented  at  the  121st  Convention,  October  5-­‐8,  2006.    San  Francisco,  CA.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐10.    Dalton,  C.    (2013).    ‘Future  Music’s  guide  to  mastering:    Understanding  dynamic  range  and  compression.’    Available:    http://www.musicradar.com/tuition/tech/future-­‐musics-­‐guide-­‐to-­‐mastering-­‐understanding-­‐dynamic-­‐range-­‐and-­‐compression-­‐574533.    Last  accessed  05/11/13.    Davis,  G.    Jones,  R.    (1990).    Yamaha:    Sound  Reinforcement  Handbook.    2nd  Ed.    Milwaukee:    Hal  Leonard.    p.12,  p.13.    Evens,  A.    (2005).    ‘Sound  Ideas:  Music,  Machines,  and  Experience,  Volume  27.’    Minneapolis,  MN:    University  of  Minnesota  Press.    p.30.    Floru,  F.    (2005).    ‘Demystifying  Analog  Circuits  in  Professional  Audio  Applications.’    In:    Audio  Engineering  Society  Convention  Paper  6455  Presented  at  the  118th  Convention,  May  28-­‐31,  2005.    Barcelona,  Spain.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐16.    

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Guttenburg,  S.    (2013).    ‘Why  is  engineer  who  recorded  Nirvana  still  using  analog  tape?.’    Available:    http://news.cnet.com/8301-­‐13645_3-­‐57601739-­‐47/why-­‐is-­‐the-­‐engineer-­‐who-­‐recorded-­‐nirvana-­‐still-­‐using-­‐analog-­‐tape/.    Last  accessed  30/10/13.    Hamasaki,  K.,  et  al.    (2012).    ‘Audio  Recording  and  Mastering  Systems.’    Journal  of  the  Audio  Engineering  Society,  60  (1/2)  January/February.    p.94.    Hjortkjaer,  J.,  Walter-­‐Hansen,  M.    (2014).    ‘Perceptual  Effects  of  Dynamic  Range  Compression  in  Popular  Music  Recordings’.    Journal  of  the  Audio  Engineering  Society,  62  (1/2)  January/February.    pp.37-­‐41.    Hoeg,  W.,  et  al.    (1997).    EBU  Technical  Review  -­‐  ‘Subjective  Assessment  of  Audio  Quality.’    Geneva,  Switzerland:    European  Broadcast  Union.    p.40.    Holmes,  A.    (2013).    ‘Home  Mastering  With  Software.’    Music  Tech  Magazine.    Issue:  119,  February.    Bath:    Anthem  Publishing.    p.27.    Inglis,  S.    (2011).    ‘KRK  KNS  8400  Studio  Headphones  Review.’    Available:    http://www.soundonsound.com/sos/mar11/articles/krk-­‐kns8400.htm.    Last  accessed  17/03/14.    Izhaki,  R.    (2008).    ‘Mixing  Audio:    Concepts,  Practices  and  Tools.’    Oxford:    Focal  Press.    p.231,  p.232.    Johnson,  R.,  Onwuegbuzie.    (2004).    ‘Mixed  Methods  Research:    A  Research  Paradigm  Whose  Time  Has  Come.’    American  Educational  Research  Journal,  33  (7)  October.    pp.14-­‐26.    Johnston,  J.,  Musialik,  C.    (2012).    ‘Signal  Processing  for  Audio.’    Journal  of  the  Audio  Engineering  Society,  60  (1/2)  January/February.    pp.104-­‐105.      Johnston,  J.,  Spors,  S.    (2012).    ‘Spatial  Audio.’    Journal  of  the  Audio  Engineering  Society,  60  (1/2)  January/February.    pp.105-­‐106.    Jung,  W.    (2005).    ‘OP  Amp  Applications  Handbook.’    Oxford:    Newnes.    pp.686-­‐852.              Katz,  B.    (2007).    Mastering  Audio:    the  art  and  the  science.    2nd  Ed.    Oxford:    Focal  Press.    p.12,  p.152,  p.215.    Kemp,  M.    (2000).    ‘The  Digital  Analogue:    The  Sintefex  Audio  Replicator  FX8000.’    Available:    http://www.sintefex.com/docs/appnotes/DigAn.PDF.    Last  accessed  19/11/13.    Kirn,  P.    (2013).    ‘Explains  Why  Difference  Between  Analog,  Digital  Isn’t  What  Most  People  Think’.    Available:    http://createdigitalmusic.com/2013/07/video-­‐explains-­‐why-­‐difference-­‐between-­‐analog-­‐digital-­‐isnt-­‐what-­‐most-­‐people-­‐think/.    Last  accessed  21/04/14.  

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 Lambert,  M.    (2010).    ‘Pluig-­‐in  Modelling’.    Available:    http://www.soundonsound.com/sos/aug10/articles/modelling-­‐plugins.htm.    Last  accessed  21/04/14.    Levine,  N.,  Skolnick,  D.    (1997).    ‘Digital  Signal  Processing  101  An  Introductory  Course  in  DSP  System  Design:    Part  1’    Analog  Devices:    Analog  Dialogue,  31  (1).    pp.1-­‐23.    Linkwitz,  S.    (2009).    ‘The  Challenge  to  Find  the  Optimum  Radiation  Pattern  and  Placement  of  Stereo  Loudspeakers  in  a  Room  for  the  Creation  of  Phantom  Sources  and  Simultaneous  Masking  of  Real  Sources.’    In:    Audio  Engineering  Society  Convention  Paper  7959  Presented  at  the  127th  Convention,  October  9-­‐12,  2009.    New  York,  NY.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐11.    Lockwood,    D.,  White,  P.,  Robjohns,  H.    (2013).    ‘The  Studio  SOS  Book:    Solutions  and  Techniques  for  the  Project  Recording  Studio’.    Oxon:    Focal  Press.    p.197,  p.217.      McLeod,  S.    (2008).    ‘Qualitative  Quantitative  –  Simply  Psychology’.    Available:    http://www.simplypsychology.org/qualitative-­‐quantitative.html.    Last  accessed  04/12/13.    Mimilakis,  S.,  et  al.    (2013).    ‘Automated  Tonal  Balance  Enhancement  for  Audio  Mastering  Applications’    In:    Audio  Engineering  Society  Convention  Paper  8836  Presented  at  the  134th  Convention,  May  4-­‐7,  2013.    Rome,  Italy.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐7.    Morrell,  M.,  Reiss,  J.    (2009).    ‘Dynamic  Panner:    An  Adaptive  Digital  Audio  Effect  for  Spatial  Audio’.    In:    Audio  Engineering  Society  Convention  Paper  7931  Presented  at  the  127th  Convention,  October  9-­‐12,  2009.    New  York,  NY,  USA.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐20.    Munro,  K  J.,  et  al.    (2013).    ‘Hear  and  Now:    Why  GPs  Need  to  Think  Again  About  Age-­‐Related  Hearing  Loss’.    Health  Service  Journal,  November.    London:    EMAP  Publishing  Limited.    pp.1-­‐17.    Murphy,  C.    (2013).    ‘Efficient  Implementation  of  Analog  Signal  Processing  Functions  in  Xilinx  All  Programmable  Devices’  (White  Paper).    San  Jose,  CA:    Xilinx,  Inc.    Peoples,  G.    (2011).    ‘What  Are  Young  Active  Consumers  of  Digital  Music  Worth?’.    Available:    http://www.billboard.com/biz/articles/news/1178396/what-­‐are-­‐young-­‐active-­‐consumers-­‐of-­‐digital-­‐music-­‐worth.    Last  accessed  15/04/14.    Perez-­‐Gonzalez,  E.,  Reiss,  J.    (2009).    ‘Automatic  Equalization  of  Multichannel  Audio  Using  Cross-­‐Adaptive  Methods.’    In:    Audio  Engineering  Society  Convention  Paper  7830  Presented  at  the  127th  Convention,  October  9-­‐12,  2009.    New  York,  NY.    New  York,  NY:    Audio  Engineering  Society.    pp1-­‐7.  

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 Pickering,  M.    (2008).    ‘Research  Methods  for  Cultural  Studies.’    Edinburgh:    Edinburgh  University  Press.  p.19.        QSC  Audio.    (1998).    ‘ABX  Comparator:    User  Manual.’    California:    QSC  Audio  Products.    p.3.    Riikonen,  V.,  et  al.    (2008).    ‘An  Augmented  Reality  Audio  Mixer  and  Equalizer.’    In:    Audio  Engineering  Society  Convention  Paper  7372  Presented  at  the  124th  Convention.    May  17-­‐20,  2008.    Amsterdam.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐8.    Robjohns,  H.    (2002).    ‘Practical  Mixing’.    Available:    http://www.soundonsound.com/sos/jan02/articles/practicalmixing.asp.    Last  accessed  11/03/14.    Robjohns,  H.    (2010).    ‘Analogue  Warmth:    The  Sound  Of  Tubes,  Tape  &  Transformers.’    Available:    http://www.soundonsound.com/sos/feb10/articles/analoguewarmth.htm.    Last  accessed  19/11/13.    Robjohns,  H.    (2013).    ‘Slate  Raven  MTX’.    Sound  On  Sound  Magazine.    Vol:    28,  Issue  7,  May.    Cambridge:    SOS  Publications  Group.    p.26,  p.27.    Sale,  J.,  et  al.    (2002).    ‘Revisiting  the  Quantitative-­‐Qualitative  Debate:    Implications  for  Mixed-­‐Methods  Research.’    International  Journal  of  Methodology:    Quality  and  Quantity,  36  (1)  February.    pp.43-­‐53.      Sandler,  M.,  et  al.    (2014).    ‘The  Mathematics  of  Mixing’.    Journal  of  the  Audio  Engineering  Society,  62  (1/2)  January/February.    pp.4-­‐13.    Scott,  J.,  Youngmoo,  K.    (2013).    ‘Instrument  Identification  Informed  Multi-­‐Track  Mixing’.    Proceedings  of  the  14th  International  Society  for  Music  Information  Retrieval  Conference.    Curitiba,  Brazil.    Philadelphia,  PA:    MET-­‐lab.    pp.1-­‐6.      Senior,  M.    (2009).    ‘Compression  Made  Easy:    Demystifying  Compressor  Controls  &  Parameters.’    Available:    http://www.soundonsound.com/sos/sep09/articles/compressionmadeeasy.htm.    Last  accessed  05/11/13.    Silverman,  D.    (2008).    ‘Doing  Qualitative  Research:    A  comprehensive  Guide.’    London:    Sage  Publications.    p.8.    Sterne,  J.    (2006).    ‘The  Death  and  Life  of  Digital  Audio.’    Journal  of  Interdisciplinary  Science  Reviews,  31  (4)  December.    pp.338-­‐348.    Stillman,  D.    (2013).    ‘ProTools  No  Longer  The  Most  Popular  DAW?’.    Available:    http://www.fugitivesounds.org/protools-­‐no-­‐longer-­‐the-­‐most-­‐popular-­‐daw/.    Last  accessed  20/11/13.  

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 Sturmel,  N.,  et  al.    (2012).    ‘Linear  Mixing  Models  for  Active  Listening  of  Music  Productions  in  Realistic  Studio  Conditions.’    In:    Audio  Engineering  Society  Convention  Paper  8594  Presented  at  the  132nd  Convention,  April  26-­‐29,  2012.    Budapest,  Hungary.    New  York,  NY:    Audio  Engineering  Society.    pp.2-­‐10.    Swami,  V.,  et  al.    (2013).    ‘Metalheads:    The  Influence  of  Personality  and  Individual  Differences  on  Preference  for  Heavy  Metal.’    Journal  of  Psychology  of  Aesthetics,  Creativity  and  the  Arts,  7  (4)  July.    pp.377-­‐383.    Thornton,  M.    (2007).    ‘Getting  The  Most  From  Your  Pro  Tools  System’.    Available:    http://www.soundonsound.com/sos/dec07/articles/ptworkshop_1207.htm.    Last  accessed  11/03/14.    Tromp,  H.    (2011).    ‘A  Basic  Guide  to  Mixing  and  Mastering.’    Available:    http://audio.tutsplus.com/tutorials/mixing-­‐mastering/a-­‐complete-­‐guide-­‐to-­‐mixing-­‐and-­‐mastering/.    Last  accessed  05/11/13.    Try,  A.    (2011).    ‘What  is  the  Best  DAW  for  Beginners?’.    Available:    http://music.tutsplus.com/articles/what-­‐is-­‐the-­‐best-­‐daw-­‐for-­‐beginners-­‐-­‐audio-­‐11773.    Last  accessed  11/03/14.    Vaus,  D.    (2002).    ‘Surveys  in  Social  Research.’    5th  Ed.    Crow  Nest,  Australia:    Allen  &  Unwin.    p.94.    Vickers,  E.    (2010).    ‘The  Loudness  War:    Background,  Speculation  and  Recommendations.’    In:    Audio  Engineering  Society  Convention  Paper  8175  Presented  at  the  129th  Convention,  November  4-­‐7,  2010.    San  Francisco,  CA.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐27.    White,  P.    (1996).    ‘Fixing  The  Mix,  Part  1:  Salvage  Techniques.’    Available:    https://www.soundonsound.com/sos/1996_articles/jul96/fixthemix.html.    Last  accessed  05/11/13.    White,  P.    (1998).    ‘Choosing  A  Recording  Setup,  Part  1.’    Available:    http://www.soundonsound.com/sos/jul98/articles/recordingopt1.html.    Last  accessed  30/10/13.    Yu,  R.,  et  al.    (2004).    ‘MPEG-­‐4  Scalable  to  Lossless  Audio  Coding’.    In:    Audio  Engineering  Society  Convention  Paper  6183  Presented  at  the  117th  Convention.    October  28-­‐31,  2004.    San  Francisco,  CA.    New  York,  NY:    Audio  Engineering  Society.    pp.1-­‐14.      

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8  -­‐  Appendices                  

 The  following  is  a  link  to  the  portfolio  website  that  will  accompany  this  project  and  will  contain  a  digital  copy  of  this  project  under  the  ‘Final  Year  Project’  tab  in  the  menu  bar.        http://myportfolioforaudio.wordpress.com        The  accompanying  digital  versatile  disc  (DVD)  also  contains  a  digital  copy  of  this  project  along  with  the  original  project  file  and  the  four  sample  clips  played  to  the  test  subjects’  and  can  be  found  inside  the  front  cover.    

8.1  -­‐  Further  Reading.    The  following  consists  of  books,  journals,  and  useful  website  links  that  may  aid  any  future  investigations  into  the  subject  area.    

8.1.1  –  Books.    Cousins,  M.,  Hepworth-­‐Sawyer,  R.    (2013).    ‘Practical  Mastering:    A  Guide  to  Mastering  in  the  Modern  Studio.’    Oxon:    Focal  Press.    Davis,  G.,  Jones,  R.    (1990).    ‘Sound  Reinforcement  Handbook.’    2nd  Ed.    Milwaukee:    Hal  Leonard  Corporation.    Gibson,  D.    (2005).    ‘The  Art  of  Mixing.’    2nd  Ed.    Boston:    Artist  Pro  Publishing.    Huber,  D.,  Runstein,  R.    (2010).    ‘Modern  Recording  Techniques.’    7th  Ed.    Oxford:    Focal  Press.    Izhaki,  R.    (2008).    ‘Mixing  Audio:    Concepts,  Practices  and  Tools.’    Oxford:    Focal  Press.        Jung,  W.    (2005).    ‘OP  Amp  Applications  Handbook.’    Oxford:    Newnes.        Katz,  B.    (2007).    ‘Mastering  Audio:    the  art  and  the  science.’    2nd  Ed.    Oxford:    Focal  Press.    Lockwood,    D.,  White,  P.,  Robjohns,  H.    (2013).    ‘The  Studio  SOS  Book:    Solutions  and  Techniques  for  the  Project  Recording  Studio’.    Oxon:    Focal  Press.        Pickering,  M.    (2008).    ‘Research  Methods  for  Cultural  Studies.’    Edinburgh:    Edinburgh  University  Press.    Silverman,  D.    (2008).    ‘Doing  Qualitative  Research:    A  comprehensive  Guide.’    London:    Sage  Publications.      

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 Vaus,  D.    (2002).    ‘Surveys  in  Social  Research.’    5th  Ed.    Crow  Nest,  Australia:    Allen  &  Unwin.        

8.1.2  –  Journals.    ‘American  Educational  Research  Journal’.  New  York:    JSTOR.      ‘Health  Service  Journal’.    London:    EMAP  Publishing  Lt    ‘International  Journal  of  Methodology:    Quality  and  Quantity’.    New  York:    Springer.    ‘Journal  of  Psychology  of  Aesthetics,  Creativity  and  the  Arts’.    Washington,  DC    :APA  Division  10.    ‘Journal  of  Interdisciplinary  Science  Reviews’.    London:    Institute  of  Materials,  Minerals  &  Mining  Professionals.    ‘Journal  of  the  Audio  Engineering  Society’.    New  York:    Audio  Engineering  Society.    ‘Organised  Sound’.    Cambridge:    Cambridge  University  Press.        

8.1.3  –  Magazines.    ‘Computer  Music’.    Bath:    Future  Publishing  Ltd.    ‘Music  Tech’.    Bath:    Anthem  Publishing.        ‘Sound  On  Sound’.    Cambridge:    SOS  Publications  Group.        

8.1.4  –  Websites.    www.soundonsound.com    www.audio.tutsplus.com    www.musicradar.com    www.emusician.com    www.musicianstools.wordpress.com    www.synthtopia.com    www.musictech.net    

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8.2  -­‐  Equipment  List.    

• AKG  ‘C1000S’  condenser  microphone.  • AKG  ‘C3000’  condenser  microphone.  • Apple  ‘Logic  Pro  9.1.8’.  • Apple  ‘Macbook  Pro’  with  2.5  GHz  Intel  Core  i5  processor  and  8GB  of  

random  access  memory  (RAM).  • Apple  ‘Mac  Pro’  with  2.8  GHz  Intel  processor  and  16GB  of  RAM.  • Cranesong  ‘IBIS’  discrete  class  A  equalizer.  • DBX  ‘PB-­‐48’  patchbay.  • Focusrite  ‘Saffire  Mix  Control  3.4’.  • Focusrite  ‘Saffire  Pro  24’  audio  interface.  • Focusrite  ‘Saffire  Pro  40’  audio  interface.  • Genelec  ‘2029A’  studio  monitors.  • KRK  ‘KNS-­‐8400’  studio  monitor  headphones.  • Mackie  ‘MR8’  studio  monitors.  • Manley  ‘Variable  MU  Stereo  Compressor/Limiter’.  • SSL  ‘Alpha  Link  MADI  AX’  audio  converters.  • SPL’  Vitalizer  MK  2’  stereo  enhancer.  • TL  Audio  ‘Ivory  5051  MK2’  mono  valve  compressor.  • Toft  ‘ATB  24’  analogue  mixing  console.  • XLR,  TRS  and  TS  cables.  

 The  following  are  links  to  the  user  manuals  of  some  of  the  equipment  used  in  the  project:    AKG  ‘C1000S’  -­‐  http://www.akg.com/C1000+S-­‐1039.html?pid=978    AKG  ‘C3000’  -­‐  http://www.akg.com/C3000-­‐1039.html?pid=1026    Cranesong  ‘IBIS’  -­‐  http://www.cranesong.com/ibis_manual_rev1.pdf        Focusrite  ‘Saffire  Mix  Control  3.4’  -­‐  http://global.focusrite.com/downloads?product=Saffire+PRO+40    Manley  ‘Variable  MU  Stereo  Compressor/Limiter’  -­‐  http://www.manley.com/content/pdf/PRO_Manuals/Var%20Mu/STEREO%20LIMCOM%20manual.pdf    TL  Audio  ‘Ivory  5051  MK2’  -­‐  http://www.tlaudio.co.uk/docs/about/pdf_manuals/ivory_2/5051_Mk-­‐2_Manual.pdf              

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8.3  -­‐  Screenshots.    

 Figure  3.1  –  Screenshot  of  the  edit  window  of  the  structured  project.  

 

 Figure  3.2  –  Screenshot  of  recorded  percussion  and  Rhodes  sample.  

 

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 Figure  3.3  –  Screenshot  of  the  VST  used  for  the  creation  of  one  of  the  bass  parts  for  the  project.  

 

8.4  -­‐  Completed  Questionnaires.  

 The  following  pages  consists  of  the  completed  questionnaires  along  with  the  ethics  form,  front  sheet,  consent  form  and  playback  order  of  the  listening  tests  conducted.