Audient - Asp008 Manual

MODE

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LINE

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PK

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1620

24SIG

44.148

88.296

operationmanual

©audient 11/2003

Copyright 2003. All rights reserved.

The information in this document is subject to change without notice.

Audient plc makes no warranty of any kind with respect to the material in this documentand shall not be liable for errors contained herein or for incidental or consequentialdamages related to the use of the material.

No part of this document may be reproduced without the prior written consentof audient plc.

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Contents

IMPORTANT SAFETY INSTRUCTIONS............................................................5UNPACKING ..................................................................................................7MAINS POWER SUPPLY.................................................................................7VOLTAGES.....................................................................................................7FUSES ...........................................................................................................7MECHANICAL INSTALLATION ........................................................................7ANALOGUE INTERFACES ...............................................................................8PIN CONVENTIONS .......................................................................................8ANALOGUE INTERFACES (CONT) ...................................................................9DIGITAL INTERFACES...................................................................................10DIGITAL INTERFACES (CONT) ......................................................................11SAMPLE RATE .............................................................................................14FORMAT .....................................................................................................14LOCK ...........................................................................................................14VARIABLE IMPEDANCE: WHAT IS IT AND WHAT DOES IT DO?....................15SPECIFICATIONS .........................................................................................17WARRANTY.................................................................................................18

Operation Manual

4

Introduction

©audient 11/2003

Thank you for buying this Audient product.

The ASP008 features eight ultra high quality microphone preamplifiers using an 8transistor discrete Class A front end with extended bandwidth and a noise floor closeto the theoretical Johnson limit. Carefully chosen close tolerance components are usedto achieve high CMRR at all gain settings and distortion is minimised to less than0.001% at 20dB gain and +10dBu output.

This outstanding technical performance delivers a mic amp with incredible transparencyand detail without colouration or other unwanted artefacts.

Each Mic amp also features switchable input impedance, allowing the user to explorethe subtle variations in microphone character that are determined by output termination.

All channels include an XLR input, ‘soft start’ 48V phantom power, switchable inputimpedance, 25-250Hz hi-pass filter as well as line input selection. Channels 1 and 2also feature a 20dB attenuator and a high-impedance Instrument/DI input on a frontpanel mounted jack. LEDs provide indication of signal present and overload. Digitaloutput options are available in addition to the standard balanced analogue outputs,making the ASP008 an ideal “front-end” for any DAW or ProTools system .

We have designed this equipment to provide you with the best possible tool to dealwith today’s demanding requirements. We have taken a great deal of pride and carein the manufacture of this equipment so that it will provide consistent and reliableperformance. Please take a little time to study the contents of this manual so that youcan be sure of getting the best performance from this equipment.

Operation Manual

5

Introduction

©audient 11/2003

RISK OF ELECTRIC SHOCK DO NOT OPEN

RISQUE DE CHOCNE PAS ENLEVER

CAUTION ATTENTION

WARNING THIS EQUIPMENT MUST BE EARTHEDDO NOT EXPOSE TO RAIN OR MOISTURE

IMPORTANT SAFETY INSTRUCTIONS

Please read all of the following instructions and save themfor later reference before attempting to connect the

ASP008 to the AC power source.

Operation Manual

6

Introduction

©audient 11/2003

EARTH This unit is connected via its power cord to the mains safetyearth. NEVER OPERATE THE UNIT WITH THIS EARTHCONNECTION REMOVED.

COVERS DO NOT remove the covers. Refer servicing to qualified personnelonly.

VOLTAGE ASP008s are set to operate only at the voltage indicated on therear panel.CHECK that the correct voltage is available beforeconnecting the AC mains supply.

FUSES CHECK that the fuse fitted is the correct type for the local mainsvoltage. ALWAYS replace fuse with the correct type.

MOISTURE DO NOT expose the unit to rain or moisture. If the ASP008should become so exposed REMOVE the mains power immediately.

CABLES PROTECT the mains power cord from damage though impact orabrasion.

HEAT ALWAYS site the ASP008 away from sources of heat includingdirect sunlight and ensure adequate ventilation around the unit.

IMPORTANT SAFETY INSTRUCTIONS

Operation ManualInstallation

7©audient 11/2003

Unpacking

Mains power supplyVoltages

Fuses

Your ASP008 has been carefully andmeticulously tested and inspected beforedespatch.

Please check for any signs of transitdamage. If any signs of mishandling arefound please notify the carrier and yourdealer immediately.

Your ASP008 Series Mic Pre packingshould contain an ASP008 rack unit, anda mains power cable, along with thismanual.

The ASP008 will be set and marked foreither 230V or 115v operation. 230Vmodels will operate without performancedegradation from 210V to 250V. 115Vmodels will accept from 105V to 125V. Donot attempt to operate the unit outside therelevant range defined above.

For 100V operation please contact yourdealer.

Mechanical InstallationThe ASP008 rack unit is convection cooledto avoid the noise nuisance of fans, so careshould be taken not to obstruct the unit’sventilation holes. Adequate air flow mustbe provided within rack cases above andbelow the ASP008 to prevent the unitfrom overheating.

Please note that the fuse ratings for thetwo voltage ranges are different, 20mmT250mA for 230V units and 20mmT500mA for 115/100V models. Alwaysreplace fuses with the same type.The mains fuse is very unlikely to failunder normal use and caution should beexcercised if a failure should occur. Checkfor the correct mains voltage, condition ofthe mains cord and integrity of the mainssupply before replacing the fuse.


8©audient 11/2003

Analogue interfacesThe ASP008 has been designed anddeveloped to provide highly robustsystem integration interfaces, allowingworry-free system hook-up under themost demanding situations.

Pin conventions To unbalance the outputs of the ASP008the -ve Pin should be connected to itsadjacent 0v pin at the output of theASP008.

Similarly, inputs from unbalanced sourcesshould be connected via twin screenedcables with the -ve Pin connection tied tothe screen at the unbalanced source.

MICROPHONE INPUTS MICROPHONE INPUTS

5 16 27 38 4

LINE OUTPUTSLINE INPUTS

Inputs and outputs are implementedusing advanced electronically balancedtopologies and are fitted with extensiveRFI rejection networks.

Additionally, Channels 1 and 2 have frontpanel mounted unbalanced highimpedance jack inputs to allowinstruments to be directly connected tothe ASP008.

Line level inputs and outputs are providedon 25 pin D Sub female type connectorswith 4-40 screw thread jack posts. Wiringis in accordance with the TascamTM DA88convention. Pin allocations are shown indetail on the next page

Electronically balanced microphone inputsare provided on 3pin XLR femaleconnectors with Pin 2 Hot and Pin 3 Cold.Pin 1 is permanently connected to theASP008 chassis and thereby to the safetyearth.


9©audient 11/2003

C H A N N E LN U M B E R

+ V ES IGNAL

-VES IGNAL

SCREEN

D-SUB P IN

1 2 4 12 25

2 1 0 23 11

3 2 1 9 22

4 7 20 8

5 1 8 6 19

6 4 17 5

7 1 5 3 16

8 1 14 2

Note : Al l undesignated pins areunconnected. Al l screen connect ions arejo ined ins ide the uni t and connected tometa lwork ear th .

++++

PIN 1PIN 13

1

2 4 6

3 75

8

WIRING SIDE OF FREE MALE CONNECTOR

Important : When preparing your D-SUB interface cables please notethat the maximum shell size thatcan be accommodated is 18 x60mm.

In order to maintain optimum EMCperformance it is important that screensare properly connected at both ends ofcable runs. In this way theelectromagnetic shield provided by theequipment chassis and the cable screenswill be optimised to reject interference. Itis recommended that only high qualitybraided screen cables are used to avoidcompromising EMC performance.

Analogue interfaces (cont)


10©audient 11/2003

Two optional digital interface cards areavailable for ASP008, either one can befactory or retrofitted to all units. A coverplate is fitted to the rear of the chassiswhen neither of the options is installed.

ADATTM

Digital interfaces

Uses a 9-Pin female D-sub type connectorto provide the required 8 digital outputs(in 4 pairs - pair 1 carries channels 1/2 etc)at 44.1/48/88.2/96kHz sample rates(selectable on the front panel). Separatefan-out cables are available with XLRterminations for AES and RCA-phonoconnections for SPDIF.

AES format is selected when theassociated switch is in its normal(released) state. Depressing this switchwill set the outputs to SPDIF format.

The outputs can be set to 16/20 or 24 bitdepth using the front panel controls

This card provides ADATTM digitaloutputs at either 44.1 or 48kHz samplerates (selectable on the front panel) for all8 channels on a single ‘light pipe ‘ outputconnector. The outputs can be set to 16/20 or 24 bit depth using the front panelcontrols

AES/SPDIF

ADATAES INT WORD

CLOCK

ADATAES INT WORD

CLOCK


11©audient 11/2003

A BNC along with an INT/EXT functionselect switch is provided on both digitaloutput cards. With the switch released theASP008 will run off its internal clockgenerator. Depressing the switch allowsa master word clock to be connected viathe BNC enabling the ASP008 convertersto be sync’d to an external source. Thefront panel mounted LOCK led willilluminate when the unit is locked.

Note that the external word clockfrequency must coincide with the clockrate set on the front panel to ensure correctsynchronisation.

Word Clock

Digital interfaces (cont)

ADATAES INT WORD

CLOCK

CHANNELNUMBERS

SIGNAL(XLR PIN 2)

GROUND(XLR PIN 3)

SCREEN(XLR PIN 1)

D-SUB PIN

1+2 9 5 1 -SHELL

3+4 8 4 1 -SHELL

5+6 7 3 1 -SHELL

7+8 6 2 1 -SHELL

CHANNELNUMBERS

PHONOSIGNAL PIN

PHONOGROUND

PIN

SCREEN

D-SUB PIN

1+2 9 5 1 -SHELL

3+4 8 4 1 -SHELL

5+6 7 3 1 -SHELL

7+8 6 2 1 -SHELL

Pin configurations for AES outputs

Pin configurations for S/PDIF outputs

Operation Manual

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Functions & Controls

©audient 11/2003

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48V applies phantompower to themicrophone input ofthis channel. It is notgood practice toswitch phantom onwhile monitoring achannel, however aproprietary ‘soft start’feature is incorporatedto minimise thepotentially damagingtransients if phantomis switched ‘live’.

INST (channels 1 and 2only). This is a highimpedance 1/4” jackinput that allows thedirect connection of aguitar without the needfor an external DI box.

-20dB (channels 1 and 2only). Inserts a 20dBpad on the microphoneinput to enable veryhigh output sources tobe connected withoutrisk of overload.

With the PAD insertedthe available gain isbetween -20dB and40dB.

LINE connects theelectronically balancedD-Sub input to thechannel. Gain range is-20dB to +40dB. Notethat this inputselection overrides theINST input.

Operation Manual

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©audient 11/2003

I/PZ adjusts theimpedance of themicrophone inputThree settings areprovided 200,1200and 5000 ohms.

GAIN 0 to 60dB of gain isavailable (-20dB to40dB with PAD orLINE selected).

inverts the phase of theinput signal. This canbe particularly usefulwhen using multiplem i c r o p h o n etechniques.

Switches in the 12dBper octave high-passfilter adjustable usingthe rotary control from25Hz to 250Hz.

SIG illuminates to showthat a signal at a levelabove -25dBu ispresent on this input.

PK lights when a signallevel above +16dBu isdetected.

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Operation Manual

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©audient 11/2003

Sample rateSample rates of 44.1/44/88.2 and 96kHz aresupported. The desiredrate can be selected byrepeatedly pressing theSample Rate select switchto step through theavailable settings asindicated by the 4 yellowLEDs. The chosenselection is retained inmemory and restored afterpower down.

FormatASP008 digital outputscan be set to 16/20 or 24bit formats by repeatedlypressing the Format selectswitch. The selected bitformat is displayed on 3yellow LEDs and isretained in memory andrestored after powerdown.

LockThis green LED illuminateswhen the ASP008 externalclock input has beenselected and theconverters havesuccessfully sync’d to theexternal clock source.

Operation Manual

15

Variable Impedance

©audient 11/2003

Variable Impedance: What isit and what does it do?

Traditionally, in order to get the maximumsignal transfer between microphone andpre-amp, the recommended practice hasbeen to ensure that the input impedanceof the pre-amp is at least 5 times thesource impedance of the microphone. Inother words, a typical 200 Ohmmicrophone needs a 1kOhm inputimpedance. The mic is essentially workingwithout any load and is able to generateits maximum output voltage, optimisingthe signal to noise ratio and usuallyproviding the flattest frequency response(or at least the frequency response themanufacturer intended). However, subtlechanges in tonal quality and microphoneperformance can be invoked bydeliberately making the microphone workharder by loading it with a differentimpedance.

The timbral changes caused by this canrange from inaudible to quite dramatic,involving a complex and interactive rangeof effects including level, frequencyresponse, and transient response.

The results will generally be mostnoticable on older ribbon and dynamicmicrophones, which are transformercoupled. The loading on the transformerusually causes frequency response andlevel changes, sometimes ironing outresonances. At the same time, theincreased damping of the magnetic circuitin which the ribbon or moving coilvibrates causes changes to transientresponse. This is similar to the well knowneffect that different amps can have onelectric guitars, where the sustain isaffected. Basically, the loading on theguitar pickup "stiffens" the magnetic fieldin which the string is vibrating, opposingthe movement of the string.

Operation Manual

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Variable Impedance

©audient 11/2003

Capacitor microphones tend to be lessaffected, especially moderntransformerless types that have a lowersource impedance. The electronics inthese microphones isolates the effect ofthe loading from the capsule. Oldertransformer coupled types tend to bebetter candidates for tonal manipulation,as they have a more complex sourceimpedance.

It is difficult to predict what the effect willbe on any given microphone. Generally, ahigher input impedance (less loading)will give a more transparent, wide rangesound, while a lower input impedance(more loading) will increase warmth andreduce level. The ASP008 provides achoice of three impedances, 200 Ohm,1.2kOhm, and 5kOhm. Don't be afraid toexperiment. This is a technique that caneasily extend the use and application ofyour microphone collection. Remember,it's the sound that's important, not thetheory!

Operation Manual

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Specifications

©audient 11/2003

Specifications

Maximum I/P level +21.5dBu

Maximum O/P level +27.5dBu

THD Typically better than 0.007% at 1kHz any gain setting

EIN Better than -127.5dB @ 60dB gain/ref 150 ohms

Frequency Response -0.3dB @10Hz to -3dB @300kHz at unity gain

CMRR Better than 75dB at 1kHz and 60dB gain

Dimensions 480mm x 278mm x 44mm

Weight 4.5Kg

Power consumption 40 watts

In keeping with our policy of continuous improvement Audient plc reserves the right to alterspecifications without prior notice. E & OE

Operation Manual

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Warranty

©audient 11/2003

WarrantyYour ASP008 comes with a manufacturer’s warranty for one year from the date ofdespatch to the end user.

The warranty covers faults due to defective materials used in manufacture and faultyworkmanship only.

During this warranty period Audient will repair or at its discretion replace the faultyunit provided it is returned carriage paid to an authorised Audient service centre. Wewill not provide warranty repair if in our opinion the fault has resulted from unauthorisedmodification, misuse, negligence, act of God or accident.

We accept a liability to repair or replace your ASP008 as described above. We do notaccept any additional liability. This warranty does not affect any legal rights you mayhave against the person who supplied this product – it is additional to those rights.

Audient plc, 1 Stable Court, Herriard Park, Herriard, Hampshire, RG25 2PL

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Audient - Asp008 Manual