instructables

40W Bluetooth Portable Speaker (Improved Version!)

by Barry_L

Hey everyone! Today I'm going to show you how I built this portable speaker! After nearly 2 years of research,designing and testing, I have come up with this design. It puts out 40W of power from it's 2 tweeters, woofers andpassives, has the latest Bluetooth 4.0 with smart features, long lasting lithium ion batteries, all wrapped up in astylish plywood body. In this Instructable I have made links to all the parts, and in depth instructions on how towire and assemble it all.

Specs:

2*20W Yamaha AmplifierBluetooth 4.0 with onboard battery indicator and ground loop isolation3S Lithium Ion battery with protection and easy charging20W Woofers with tweeters + passive radiators4 hour battery life @ high volume, 8 hours medium volume

How does it sound? It trumps most high end factory made speakers like the Bose Soundlink Mini, see thevideo below for proof!

So what makes this speaker stand out from other DIY speakers?

1. This speaker has built in ground loop isolation, which eliminates interference noises coming fromthe Bluetooth module, which most other DIY speakers suffer from. This speaker has 100% cleansound.

2. Smart monitoring; so you can see the battery charge of the speaker from your phone.3. Uncompromising Bass; this speaker has been cleverly designed to put out a very impressive sound,

which puts it ahead of a lot of high end shop speakers4. The parts used can be found cheaply and reliably5. The speaker is fully disassemble-able, it can be taken apart just from unscrewing the components.6. Long lasting battery life and convenient charging options

//www.youtube.com/embed/POQiT3dlfYA

40W Bluetooth Portable Speaker (Improved Version!): Page 1

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Step 1: Parts List

UPDATE: Unfortunately several parts that I used in this build have been discontinued! I've redesigned the speakerto use different drivers (it now uses much more compact high quality full range drivers), but everything else like theamp, batteries and so on haven't changed. Here's a link to the parts for the new redesigned, simpler, and cheaperversion (It has the same sort of sound quality and same power output). I've made a kit for the parts to make thingssimpler if anybody's interested, there's more info on the changed parts over here:

https://www.etsy.com/ie/listing/467986351/new-spea...

18mm Plywood3mm PlywoodIf you're laser cutting, you can download the laser cutting files here. If you want the parts laser cut,but don't have access to a laser cutter, you can send me a message, and I'll do what I can to helpout.

Step 2: Designing the Front and Back Panels

The design for this enclosure was inspired by layersof stacked wood. From the outside, the speaker lookslike it has been built by stacking 10's of layers ofwood together, but in fact, it was built using 3 piecesof 18mm plywood glued together, followed by two3mm plywood panels on the outside. I designed thisenclosure so that it's about 2.25 liters in capacity,which is perfect for this driver/passive radiatorconfiguration.

Making the front panels:The quickest way to make the front panels is by lasercutting them. Here's a link to the laser cutting files.The laser cutter I used couldn't take wood thickerthan 3mm, so I had to layer 2 pieces on top of each

other for strength, followed by strips of MDF for extrareinforcement. All the wood in this project is gluedtogether only using wood glue. The front panels haveholes for the tweeters and woofers, as well as aservice hole to access the electronics. The backpanel has holes for the passive radiators, and smallholes for charging and a switch.

If you're designing your own front panels.. I wouldrecommend including a service hole like in mydesigning, as being able to have easy access to theelectronics is crucial in case something goeswrong/needs adjusting.

40W Bluetooth Portable Speaker (Improved Version!): Page 3

Step 3: Making the Side Panels

Next up we're going to make the side panels. These are made out of high quality 18mm plywood. Each layer onthe plywood is about 3 mm thick, with a thin veneer on the top and bottom. I would recommend using a very highquality plywood, as the inner sandwiched layers are more likely to be solid and tightly packed. On cheaperplywoods, when you cut them thinly the layers split/fall apart. For these pieces we will only be using a jigsaw and adrill with a hole saw drill bit and a wood drill bit.

1. We'll start by taking our front panel pieces and tracing the shape on to the plywood. We will thendraw an inner shape, about 8 mm in, possibly more or less, depending on skill level and quality ofthe plywood (you'll get an understanding of it quickly)

2. Next up, use the holes aw drill bit on your drill to create 4 holes on the inside of the shape, so thatthe edge of the hole saw cut lines up with the inner drawing on the wood. This gives us a sharpinner curve, and a hole to stick the jigsaw into.

3. Use the jigsaw to cut the inner shape out.4. Lastly cut the outer layer, and round the curves at the side.

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Step 4: Gluing the Side Panels

The side panels are simply glued together usingwood glue. Use plenty of glue. Sandwich themtogether and put a large weight on them/clamp themto keep them tightly together while they dry.

After the piece is fully dry, we can use a jigsaw or atable saw to shave down the sides to get them to

perfectly align with each other. You can also do thisby sanding it down, but it will take significantly longer.

Once they dry, coat the inside with a thick coat ofwood glue. This is essential to prevent air leaksonce the speaker is assembled.

40W Bluetooth Portable Speaker (Improved Version!): Page 6

Step 5: Preparing the Back Panel

Now it's time to glue the passive radiators on to theback panel. Passive radiators are an alternative to abass reflex port. They allow us to extend thefrequency range of our speakers, in a more compactenclosure. They require no power to operate, as theysimply work off the air pressure within the enclosure(ie. when the driver moves outwards, the passivemoves inwards). Therefore it's extremely important tomake sure your enclosure is 100% airtight whencomplete.

We will glue the passive radiators in place using asuper glue gel.Super glue gel is better than superglue for this application, as it's not as rigid, and allowsminimal movement, unlike normal super glue.

While we're at it, we will also add several strips ofMDF to the back using the same glue, in order tomake it harder to bend. Any vibrations within theenclosure will spoil the sound.

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Step 6: Positioning the Electronics

As you can see in the pictures above, there are a lotof electronics to fit inside this enclosure. It's importantto plan out your positions for the electronics beforeyou start making anything. Make sure everything willfit! It's also important to select the best positions ofcomponents that may need to beserviced/inspected later on down the line.

In this design I decided to place the components sothat I have very easy access to boards like the

amplifier and bluetooth module. Other componentslike the crossovers may never need to be inspected,so I have placed them further away from the servicinghole. The crossovers are positioned directlyunderneath the cutout for the right woofer, so if I needto access it I can unscrew the woofer and access it.The other components are directly underneath theservice hole, which also gives me easy access.

Step 7: Electronics Schematic

Here's a schematic for the electronics used in thisproject. If you use the parts linked on the parts liststep, it's pretty simple. All you'll need is a solderingiron and solder (and maybe some cable ties to cleanthings up afterwards). Measure out the lengths ofcable you need in relation to how you're positioningyour components. The less excess cables the better.

If you're new to speaker building, or would like abetter understanding of how the components work,read on. Otherwise you can skip the electronicssteps.

40W Bluetooth Portable Speaker (Improved Version!): Page 8

Step 8: Understanding the Battery Pack

Safely using lithium ion batteries confuses a lot of people. But in reality it's quite simple. There are 3 things thatyou need for a lithium ion battery pack:

1. Lithium Ion battery cells2. Battery protection board3. Lithium Ion Charger/charger board

Buying good lithium ion cells is important.There are plenty of fake cells online for sale in both China,America and Europe. The easiest thing to do is to find a reliable genuine battery type that sells quite cheaply. Agreat example of this would be Samsung's pink 18650 batteries. Since they're so cheap, Chinese companies don'tbother creating replicas because the original ones simply cost to little for it to be worth their while to designsomething cheaper. As a result, you end up with genuine battery cells by Samsung at a cheap price.

The next thing you need is a battery protection board. These circuit boards will protect your batteries from overcharging, over discharging, short circuiting and more. The exact safety features vary a bit from board to board.Battery protection boards are an essential item, as lithium ion batteries are very sensitive, and need specificconditions to work under, or else you may run the risk of the batteries dying/catching fire/exploding.

Lastly, a lithium ion battery charger is important. These chargers send power to the batteries to charge them, butwill also cut off/reduce power depending on the battery pack's voltage. It's important to make sure that yourlithium ion battery charger IS a charger, and NOT just a power adapter. A lot of the 'chargers' listed on eBayare in fact just power adapters. It's important to check the reviews and the item descriptions, as you definitely don'twant to get the two mixed up.

If you would like to understand more about charging/managing lithium ion batteries, I've written more about them here. See steps 3 and 4.

40W Bluetooth Portable Speaker (Improved Version!): Page 9

Step 9: Wiring the Battery Pack

Before we start assembling anything, it's importantto make sure that the battery voltages for eachcell are exactly the same. Any difference in voltagewill confuse the protection board and potentially killthe batteries when charging. If the voltages areslightly off, you can use one of these circuits to charge each battery individually, so you can get them all toexactly the same voltage.

Once the voltages are balanced, we can start work onthe battery pack. This battery holder is worth getting,as it keeps the batteries neatly one place. I wouldrecommend replacing the wires on them though, asthey're too thin to transport the power that we need.

Follow the schematic from earlier to wire up thebattery protection board, as well as the switch andcharger. Make sure you wire the charging jack theright way around!! See the image above as reference.The right pin (bent) can be removed. The middle pin

is for positive power, and the left pin is for ground.Plug the jack into your charger and check voltageswith a multi-meter before connecting it to theprotection circuit to make sure you have it wiredcorrectly.

Slot in the batteries and make sure that everythingworks. If it does, you can clean up the wires a bit bytucking them on the underside of the battery holderusing tape.

We will now also add in the voltage step upconverter. Once the inputs are connected, using amulti-meter, measure the output connectors to seethe voltage output. We want to adjust the voltageoutput to 14v. We do this by getting a smallscrewdrivers, and twisting the copper screw on thePCB, until we reach 14v. It's exactly the same operation as this, except on a slightly different board.

40W Bluetooth Portable Speaker (Improved Version!): Page 10

Step 10: Wiring the Bluetooth Module and Amplifier

To save space and keep everything in one place, theBluetooth module has been stacked on top of theamp. If you plan on doing the same, make sure toleave a decent gap between the amp's PCB andthe BT Module's PCB, as they both need airflow tocool down, and you run the risk of short circuiting ifthey're touching each other. I glued the BT module ontop of the amp's capacitors using hot glue. If youalready have a Bluetooth Module that you would liketo reuse from a previous build, that runs off 5V, Iwould highly recommend attaching this Ground Loop Isolator to the power inputs of the Bluetooth module,as it will eliminate unwanted ground loop noisescreated by the Bluetooth chip.

The Output from the BT module can be connected tothe Input of the amplifier. If you would like to connectfunction buttons to the Bluetooth module, now is the

time to do so. Simple push to make switches, wiredas shown in the photo is perfect.

Connect the amplifier to the output of the step upmodule. That means it will receive 14v. Connect theBT module to the input of the step up module, whichwill result in an output between 10v and 12.6v,depending on the battery voltage. The rangingvoltage means that the BT module can monitor it. Ifyou one of the newer android versions, you will get anotification next to the BT symbol on your phone,showing the battery life left in the speaker. TheBluetooth module will work down to about 10.5v,which works quite well with the 3S batteryconfiguration. Do not connect the BT module to the14v power supply, as the maximum voltage thatthe BT module can take is 12.7v.

40W Bluetooth Portable Speaker (Improved Version!): Page 11

Step 11: Wiring the Crossovers

Now it's time to connect the crossovers. Crossovers split the audio into high and low frequencies for the woofersand tweeters. Once they're connected we can glue them in using hot glue, along with the other components. Wecan also glue in the switch and charging jack. Pay special attention to these, as it's important to get them 100%airtight. Use your hot glue smartly!

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Step 12: Gluing the Side Panel

Now it's time to glue on the side panel. Put a line of wood glue around the edge of the back panel, and then clampthe side panel on.

After it has been left to dry for a few hours, add a layer of hot glue on the inside of the joint. This is to ensure thatit's airtight, and to add more structural rigidity.

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Step 13: Making the Front Panel

We can add small bits of MDF wood to the back toadd more structural rigidity. Now we can glue in thetweeters. Since they won't be moving, we can justuse hot glue. Solder on wires for connecting it to thecrossovers, since this won't be possible once thepanel is glued on. We won't screw in the woofers just

yet. We can do that last, after everything is glued andwired.

Add a bead of glue along the front panel, and clamp ittight and leave it to dry.

Step 14: Closing Up the Enclosure

Now that the glue has dried. we can wire up theremaining woofers. Once wired we can screw themin. Give it one final test, and if everything works, thenyou can screw on the final plate over the servicinghole.

Lastly, we can sand the outside, and add a clear coatstain over it to keep the natural look of the wood.

And just like that, the speaker is finished! If you wouldlike to, you can add a cloth and plywood speakergrille to the front by layering up a few more pieces of3mm plywood, and then gluing a cloth to theunderside of the top layer.

40W Bluetooth Portable Speaker (Improved Version!): Page 14

Step 15: Further Reading/inspiration for Speakers

I have written several other Instructables that you can check out, which may give you more ideas.

My Facebook design page is a great place for inspiration. Recently I added a special section wherepeople can add their designs to the page for everybody else to see, ask questions, and make newfriends.

Sites like Etsy may give you some interesting ideas. Etsy focuses on handmade/vintage items,which means that they have a nice lineup of crafty items.

Youtube is also a great source for inspiration.

Thanks for reading this Instructable, and I hope that it will help inspire you to create something amazing. If youhave built any speakers, feel free to comment below and show them off. I'd love to see them! :)

40W Bluetooth Portable Speaker (Improved Version!): Page 15

Did you not have any problems with on/off popping sound ? Did you use the mute/standby ?

Barry are the laser cutting files for the updated version?

Hey, since you still had the chance to download the laser cutting files would you be so nice toreupload them for us since Barrys links are down and he is busy studying? This would very muchbe appreciated by a lot of us, thank you.

You said that Bluetooth module can take is 12.7v (max).

But buyers recommendation of csr8645 is 3.3-4.2v.

:(

The compenent kit is unavailable... and I was unable to find the components you used on amazon,so is there another kit/set of components that I can use to make this speaker?

take this moment to time travel Barry...

Please label all the part you used zzzzzz

Please give us exact and complete details of the items,

thanks alot

Anybody knows what kind of batterie board protection do he used?

There is so many with 12,6v : 8A, 10A, 20A...

40W Bluetooth Portable Speaker (Improved Version!): Page 16

8A, 10A, 20A is the maximum prospected current rating of the board. 8A would work fine for thisapplication but it's up to your discretion whether you trust the manufacturers rating correspondingwith its price.

Great project. I have tried with several different amplifiers and bluetooth receivers. But since theyare running on the same battery, I always got sound disturbance on the speakers. Why is this noproblem here in Barry'S project?

HI

I am selling my gear check out if you need it

https://www.ebay.co.uk/itm/182868558968

Would it make sense to physically decouple the air space of the left channel from the right channelby adding a baffle?

As it is, the pressure behind the left channel woofer will somehow influence the right channelwoofer, unless they receive identical signals (not necessarily the case in a stereo setup).

Apart from finding new locations for all the parts in a baffle-design, would I need to adapt theinternal volume? If so, how?

Calculating and building speakers is quite involved, as I slowly start to find out....

I make the same project using this components :

Speakers:

https://fr.aliexpress.com/item/2PC-3-inch-Woofer-Bass-Speaker-8OHM-20W-Neodymium-Magnetic-Surround-Speakers-Multimedia-Loudspeaker-Cone-Rubber/32817076266.html?spm=a2g0s.9042311.0.0.7QvN5l

or

http://www.ebay.com/itm/For-Sony-4-inch-4Ohm-20W-Full-Range-Audio-Speaker-Stereo-Woofer-Loudspeaker-Horn-/222269722813?hash=item33c04ed0bd:g:DbsAAOSw4shX8lYL

Tweeters:

https://fr.aliexpress.com/item/2PCS-3-inch-Silk-Film-Magnetic-TREBLE-Tweeters-Speaker-For-Bookshelf-Stereo-High-definition-5-1/32686197042.html

Passifs radiators:

http://www.ebay.de/itm/2pcs-4-inch-95mm-Bass-diaphragm-bass-passive-board-Bass-Film-/161798932475?hash=item25abf7c7fb

or

https://fr.aliexpress.com/item/2Pcs-4Inch-Loudspeaker-DIY-Bass-Speaker-Vibrating-Membrane-Passive-Bass-Woofer-Diaphragm-Plate/32779806867.html?spm=a2g0s.9042311.0.0.7QvN5l

Crossovers:

https://fr.aliexpress.com/item/2pcs-2-Way-Crossover-Filters-2-Unit-Hi-Fi-Speaker-Frequency-Divider-4-8ohm60W/32723246112.html?spm=a2g0w.search0104.3.171.pRyeEN&ws_ab_test=searchweb0_0,searchweb201602_1_10152_10065_10151_10068_10084_10083_10305_10080_10304_10082_10306_10081_10177_10110_10137_10111_10302_10060_10112_10113_10155_10114_10154_438_10056_10055_10054_10182_10059_10184_100031_10099_10078_10079_10210_10103_10073_10102_10189_10052_10053_10142_10107_10050_10051,searchweb201603_1,ppcSwitch_5&btsid=4de521f5-32ae-4833-90b5-20fe5d2141c4&algo_expid=2e31d0fa-f2e8-44a5-b390-368831a8b965-22&algo_pvid=2e31d0fa-f2e8-44a5-b390-368831a8b965

ground loop iolator:

https://fr.aliexpress.com/item/VODOOL-Ground-Loop-Noise-Isolator-Audio-Anti-jamming-Device-with-3-5mm-Audio-Interface-for-Car/32752305761.html

Battery Capacity Indicator 4 LEDs:

http://www.ebay.com/itm/9-12-6V-Battery-Capacity-Indicator-4-LEDs-Display-For-3S-Battery-/201922185165?hash=item2f038007cd

40W Bluetooth Portable Speaker (Improved Version!): Page 17

adaptateur secteur 12.6V:

http://www.ebay.fr/itm/2-Pin-EU-Plus-DC-12-6V-2A-Adapter-Charger-For-Lithium-Ion-Li-ion-LiPo-Battery/222564560953?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

with the female cnnector:

http://www.ebay.fr/itm/10PCS-DC-Power-Supply-Jack-Socket-Female-Panel-Mount-Connector-3-Pin-5-5-x-2-1mm/263082843088?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Hi Barry or any one else that can answer this, inst the CSR8645 Bluetooth 4.0 Module GroundLoop Isolation also an amplifier? I am looking at this,http://www.ebay.co.uk/itm/CSR8645-Bluetooth-4-0-Amplifier-Board-5W-5W-APT-X-Stereo-Receiver-amp-Module-/272256721372?hash=item3f63c3e1dc:g:4B8AAOSwopRYhGTA shouldn't it output 5w +5w, I might be wrong butdidn't you use this module in your other build the simple 10w speaker? So my question is, can youconnect the output from an amplifier to the input from another amplifier? if not can someone sendme a link to where to fine the Bluetooth module only. Thank you

Yes it is possible I made it with this (http://www.ebay.com/itm/DIY-KRC-86B-Bluetooth-4-0-... andthis (http://www.ebay.fr/itm/PAM8406-Digital-Class-D-Ste...

and I remember saw a video with someone making this with the CSR8645

You can sell it? I'm like it

HI

Can some give me link to crossover

Someone know the size of the passive radiator?

http://www.ebay.de/itm/2pcs-4-inch-95mm-Bass-diaph...

you're welcome :)

can i changer bettery with 18.5 v

the stepup converter wont boost the voltage when i turn the screw i tired turning it in both directionand it wont do it. Also mine has a micro usb connecter

hey ı not download you are send to mail please ilker.nalbant@hotmail.com

Hello, can somebody please share good speakers model for this case?How many ohm and what size?

2 fullrange speakers for quite cheap and good quality

https://nl.aliexpress.com/item/2pcs-HiEND-4inch-GO...

Think i find

Sony 4 inch 4Ohm 20W Full Range Audio Speaker Stereo Woofer Loudspeaker Hornhttp://www.ebay.com/itm/For-Sony-4-inch-4Ohm-20W-Full-Range-Audio-Speaker-Stereo-Woofer-Loudspeaker-Horn-/222269722813?hash=item33c04ed0bd:g:DbsAAOSw4shX8lYL

The link to the Etsy parts is broken, please update ?where can I buy the parts or find the parts list?

Hello please model of woofer and tweeter

i built it, but the Power Supply and the Case.

Because its hard to find a cheap 12.6V Power supply,I plan to use such a DC-DC converter + heatsink, adjusted to 12.6 V as Charging device which iwould solder directly to the BMS Board.

40W Bluetooth Portable Speaker (Improved Version!): Page 18

Whith that i could charge the batteries with 5V till 14V (Running Car).

Or does something speak against it?

Hello, nice job do you have part list ?

> CSR8645 Bluetooth 4.0 Module Ground Loop Isolation : OK

> YAMAHA YDA138-E - 2*20 W / 12 V :OK

> 2S Li-Ion Battery Protection Board : OK

> Battery BMS Protection PCB Board 3/4 packs 18650 Battery 3s 4s : OK

> Voltage Step Up (2-24v) 2A / MT3608

-Crossover : Model ?? // facultative if no tweeter !

-Tweeter : Model ??

-Woofer : Model ??

- Or Woofer with tweeter kit ?

If you find something good, please let me know. I also looking for a kit Woofer with tweeter

Jetley, Seriously? You're going to defend Bose?

1. Bose is a marketing company that makes mediocre speakers. They are one of the biggest ripoffsin electronics today.

2. The point here is to build something yourself. Not go to best buy and buy the same metallic sounding metallic box as everyone else.

Whileyou are likely right, this is actually going to be 20W total, your theory that the amp will go into thermal shutdown is completely wrong because it is a class D amplifier.

Class D amplifier's operate in switching mode, which gets their efficiency much higher than 90%. Assuming that it is running at full volume which usually is less than a 30% duty cycle at full power, you are looking at the IC dissipating 0.6Wof heat max. That is why the chip has no heat sink.

The reason the Bose speaker's amplifier must be thermally connected to the case is it's an old school class B amplifier. Not only does it dissipate many times more heat, it is less than half efficient, meaning the run time islower too.

This is a cool build. Nice job!

Agree what Netwizzard said.

@Jetley: Dont trash this project please. Thank you.

My point is not to trash the maker's design, but to ask that the true ratings be stated. Barry_Lhimself acknowledged that he made an unfair comparison and that the Bose Mini was the bestportable speaker for its size.

Perhaps you haven't read the YDA138 datasheet. Even class D amplifiers have losses and do gethot. The datasheet has de-rating curves of power out vs ambient temperature. These curvesindicate that the chip can only do the rated power at 25C. Since music has a very high peak-to-average power ratio, you'll probably not go into thermal limiting on normal usage, but I have hadclass D amps go into thermal shutdown on even modest power when they are not used withheatsinks. By the way, the Bose mini does use a Class D amplifier.

40W Bluetooth Portable Speaker (Improved Version!): Page 19

And yes, I'm going to defend a good company that has a large engineering staff (much bigger thantheir marketing department) that is doing innovative research and design in many areas. By yourremarks, I see you have an opinion, but little knowledge about the company or the extensivedesign work that goes into their products.

This is a good effort at a portable Bluetooth speaker and I’msure it is adequate to your purpose. However, I’m having trouble believing your40W power ratings as nothing adds up. In the photos of the parts you show anamp board with one YDA138 IC. According to the YDA138 (D3) datasheet the amp israted at 2x10W @8ohms load and 1x20W @4 ohms. It will not do 2x20W into 4 ohmspeakers. There are two-chip versions of the amp module that will do 20W/channelat 25C , but inside a sealed wooden box the amptemperature will rise somewhat above 25C and theamp will go into thermal limit should the speaker be played at max volume foran extended time. (This is one reason the Bose Mini has a metal enclosure as itwill dissipate internal heat better than wood.) Even with the two-chip amp thelisted power step up converter will not supply the power needed to make 40W.

I’m a great fan of my Bose Mini and find that its size is justright for finding a good spot to put when using it in my home and to carry ontrips. I would expect according to the laws of physics that a speaker severaltime bigger than the Mini should have more bass. To me both the power ratingand the biased comparison are misleading to Instructables members.

I made it. Best boombox around. I used a local laser cutting shop to make 10 layers of 12mm birchplywood. Barry provided the electronics kit. I found good batteries and figured out the batterycontrol circuits. This project was a pleasure. all round. Thanks, Barry.

Very cool and I love the steel grunge handle.

Handle detail!

Thanks! I was going for the steampunkt look.

This was a terrific project. I ended up learning a ton about Li-Ion batteries in the process. Plus thebox sounds fabulous. Barry is terrific. I'm thinking of doing another box one day.

How did you shield the circuit boards from the magnets? Last time I forgot to shield stuff the thingonly worked for about a week or so before it died.

Very good instructable. I'm just wandering what cause stopped you from posting all component listwith links to e-shops. With that info this instructable would be simply tye best... Now it is justcomercial spoiler to etsy ...

This is beautifully designed, beautifully made and it sounds great. Really nice instructable. I'd liketo say a word in defense of the Bose SL Mini. I dislike Bose and all the tricks they play, such as theones you demonstrate here. But the Soundlink Mini is, I believe, a somewhat miraculous device inthat its TINY size and reasonable price make it possible to have "ok" sound everywhere you go. Ican mount it to my bicycle, I can put it in an overnight bag or a small suitcase for any short trip, itsure beats listening to music through my cell phone speaker in a hotel room. I can carry the SL

o

o

40W Bluetooth Portable Speaker (Improved Version!): Page 20

Mini and my phone around the house in one hand and a can of beer in the other. Your devicesounds better, looks better, is better, and is cheaper too ... but ... it's a lot bigger and I really thinkthe SL Mini hits a sweet spot that nothing else comes close to. Yours obviously is a lot moredelicate, it would not survive being packed in a suitcase or taken out on the road on a bicycle.

One thing I really love about this project is how you combine the beautiful wood work with a simpletutorial on batteries, bluetooth, and small modern amps. You taught me a lot. Thank you.

hi friend. very nice project. where you buy this parts?

you a list?

Hey berry can you tell me the specific of the and

reminds me of the jbl Xtreme, One of the best speakers on the market. Why don't you make a JBLXtreme Diy. That would be cool.

Hey can ia ask you how many wolts are the tweeters

Ups, sorry how many watts

I want to add battery level lights, how the wiring is going to be

Hi Barry, great work! I am trying to build one. I have one question with the protection circuit.

I find a little difference when connecting the batteries, is your connection ok? Is this connectionfrom the attached file ok?

Best, Rodri

I never got 2 protection critics to work as recommended. I went with another one and it worked fine.I think the wiring diragram is wrong

Which one did you get to work?

Thank you Barry! I built it adding some lights and covered everything with a fiber fill to create a"Musical Cloud Lamp"

The only problem is that I can hear a bip (like low power sound from BT) while I play some music,does it happen to you?

Best,

Rodri

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