Bluetooth Speakers Powered by Power Bank

This is a very easy to build, yet powerful boombox. No soldering nor any knowledge of electronics needed.

You can turn your bookshelf speakers into a portable bluetooth boombox for about €30.

I chose to use a power bank as power source because of the USB charging capabilities and because you can easily swap an empty power bank with a full one. One full power bank (10000mAh) lasts 7-12 hours (depends on the volume).

Specs/ Features:
- 2-way bass-reflex speaker system (bookshelf speakers)

- USB charging (pass through power bank)

- TDA7492P 50W+50W Wireless Bluetooth 4.0 Audio Receiver Digital Amplifier Board

Step 1: Build the Box

I built the box using some scrap wood I had lying around. The handles are made from a leather belt. I think there is not much to describe here as you can design your boombox as you like it.

Step 2: Connect the Parts

Parts:

Amplifier:

TDA7492P 50W+50W Wireless Bluetooth 4.0

This is a bluetooth amplifier, which needs a 12V input. As it ships from China delivery times can be very long.

Powerbank:

Xiaomi 10000mAh power bank

I used this power bank, because it's a great bang for buck and due to its pass through charging abilities. This means you can charge your power bank while using your boombox.

5V 12V Converter:

5V USB 12V DC Converter

This is used to convert the 5V output of the power bank into 12V for the amplifier.

Connect the Parts:

It's very simple to connect the parts. Just connect the 5V 12V converter and the bookshelf speakers with the amplifier and it's done. No soldering needed.

Comments

[ChristellE1]

So I thought this might a good question.So I want to make the sane system but with 2 16cm pioneer speakers and 1 4 inch speaker.Would it possibly work but with a stronger amp and powerbank

[LuisRaygoza]

I was thinking about using 4 18650 batteries in series but this got me thinking because one of this Xiaomi banks is cheaper than the 18650's. But is the amp capable of reaching full volume due the "low" current given by the bank? this banks usually have 2amps max output and when you step up the voltage to 12v the current will drop to less than 1.5 amps and this amplifier needs about 3-3.5 amps at 12v

[JorgeDiesel]

Nice mate!

How do they sound? =)

I bought the same amp and was going crazy trying to figure out how to power it because I was going to use an ebay lithium battery @9800mAh but they seem fishy!

This looks so easy! Can you just assure that it powers the amp enough so it sounds good? =)
(it would have 2*25w woofers and 2*30w tweeters (8ohms both of them) connected to crossovers.)

[Horang]

Sup!

I can assure they do sound good. They get very loud without problems. Only when I turned them really loud, I got some crackling noises. But up to a certain volume, which is already very loud, they sound very decent.

[IggyP]

Nice touch, i was thinking too about a power bank powered boombox, can you pls tell for how long time your power bank will last?

[Horang]

One powerbank will last about 7-12 hours, depending on the volume.

[tikka88]

nice build. just wondering about the amp. it might be a bit overkill since the 5v to 12v adapter puts out like 500mA * 12v = 6w of power. so you could get as much "umpf" with a lot smaller amp. like pam8043 chipamp, and would not need the boost converter at all. it is a 3 +3w 5v amp. There are also boards with built-in bluetooth and this chip. I have used i quite a few of those chips and now building something way bigger. found your instructable while looking for a suitable amp for my project :) but anyway, good work. keep tinkering.

[jbeauforêt]

What amp do you recommend with built in Bluetooth, 5v and 3W? I only find chips which need to be solded together an I am no good at soldering... :-)

[tikka88]

Just look for them in aliexpress.com or DX.com. search for "5v audio amplifier bluetooth" and gonna get a lot of choices. They are all basicly The same AMP in diffrent form. Allmost all are pam8043 + similiar bluetooth chips on most. Some have remotes even. And radio + USB decoding on The same board. I recommend you choose one of The panel type amps with The remote and all that. :) hope this helps. (Also, EBay) :)

[jbeauforêt]

I'll try that. thank you very much!

[tikka88]

no problem. i suggest looking at things like this. http://www.aliexpress.com/item/5V-Bluetooth-Receiv...

really simple to wire up and has : 2x3w amp (pam8043) Bluetooth 2.1 compatible receiver chip. Fm radio, IR remote, USB mp3 decoding player and AUX input as well. and quite cheap set if u consider it has it all. U can most likely run it off a single 18650 cell or any other single cell li-po or Li-ion battery. just remember to use protected batteries always and get a micro USB-to-one cell charging board to complete your boombox needs. Just add evenly charged cells in parallel to get longer battery life. if protected no need for any sort of balance charger, just use one charging board for the set.

[jbeauforêt]

I will now try this one: http://eud.dx.com/product/2-channel-3w-pam8403-audio-amplifier-board-red-844146300#.VqtHUrLhCHs with an USB BT-Dongle powered by a power bank. I bought 4 amps therefore I can practice a bit ;-)

[tikka88]

no problem. i suggest looking at things like this. http://www.aliexpress.com/item/5V-Bluetooth-Receiv...

really simple to wire up and has : 2x3w amp (pam8043) Bluetooth 2.1 compatible receiver chip. Fm radio, IR remote, USB mp3 decoding player and AUX input as well. and quite cheap set if u consider it has it all. U can most likely run it off a single 18650 cell or any other single cell li-po or Li-ion battery. just remember to use protected batteries always and get a micro USB-to-one cell charging board to complete your boombox needs. Just add evenly charged cells in parallel to get longer battery life. if protected no need for any sort of balance charger, just use one charging board for the set.

[Horang]

Thank you for the comment!

The smaller amp is a great idea and work as well (probably with better battery life). The idea about the amp, that I used, was that it was so easy to just plug in everything without the need of any soldering or electronics skills.

Just plug and play :)

[savaka]

For how many hours does the power bank last?

[Horang]

around 7-12 hours playback time on medium-loud volume

[savaka]

That is great!

[tomatoskins]

This looks amazingly simple! How did you make your box?

[Horang]

I used some wood planks I sawed down the right length for my bookshelf speakers and screwed them together, very simple design.