Need a good amp board for 6-8V battery

[MosMike]

I have 4 Tang Band W3-881SI 3" drivers which I intend to use for a portable boombox. The boombox will be powered by a "Magicshine" li-ion battery pack:

The voltage from this pack ranges from 6V to 8.4V

I need a good quality amplifier board for this project, so far I have found only the Adafruit MAX9744 (Stereo 20W Class D Audio Amplifier - MAX9744 ID: 1752 - $19.95 : Adafruit Industries, Unique & fun DIY electronics and kits)

Are there any other amp boards capable of outputting 2x4W @0.1%THD from a 6V pack ?

 

[DUG]

The data sheet for the IC on this board says it is rated for "Wide 4.5V to 14V Power-Supply Voltage Range" so it will work for your application.

The TPA3116 boards will also work. (Wide Voltage Range: 4.5 V – 26 V)

 

[MosMike]

The TPA3116 boards will also work. (Wide Voltage Range: 4.5 V – 26 V)

Thanks for the hint. The TPA3116 boards are more affordable. I noticed an interesting thing - according to the datasheet the TPA3116 @6V is useful only up to 2.5W and 7W @8V Basically, the input voltage dictates the output power ?

 

[DUG]

Thanks for the hint. The TPA3116 boards are more affordable. I noticed an interesting thing - according to the datasheet the TPA3116 @6V is useful only up to 2.5W and 7W @8V Basically, the input voltage dictates the output power ?

Load and supply voltage limit maximum power at a specified distortion level, but you are on the right track.

I don't call the supply voltage to an amplifier "input voltage".

The input voltage to an amplifier would be the signal voltage, audio in this case.

The input voltage to a power supply would be the supply voltage.(i.e. 115VAC or 220VAC)

IMHO

🙂

 

[MosMike]

Finally I have received my TPA3116 amp board.
I decided to buy the board with bluetooth 4.0, this one:
Wireless Digital Bluetooth 4.0 TPA3116 50W+50W Audio Receiver Amplifier Board With Mic Free Shipping-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group

The board works from 6V, but the bluetooth connection is poor - I got a max range of only 2 meters, when I press the buttons I hear cracking sounds.

The audio quality is very good, unfortunately this board has a mic but doesn't have a line input, so I can't bypass bluetooth.

Is there a tested good board with bluetooth?

 

[Jerms]

TBH you might want to persevere with your existing board. First off, try giving it more volts. Say double the current volts, 14.8-16.4....

J.

 

[doctormord]

Would guess it's due to the bt-antenna is detuned because of the mounting. You may try some crude tuning by having some mylar/capton/plastic-foil under the antenna (between these two boards).