I want to diy battery powered small speakers, please high level advice on how to match the amplifier board (finished) and speakers

Your idea is good! But technically can not break through, usb port standard power supply is only 100MA, the maximum 500MA, do amplifier power supply up to a maximum of 1W dual-channel undistorted 0.5W dual-channel, listening to voice can be, listening to music is too reluctant, do not have to consider this program. Finished mini audio on the market are generally tda2822 amplifier, I think it is also not good to listen to, I personally think also do not have to consider. If you think you can do it yourself, you look at how to do so: mono, battery 128AH, tda1521 trellis single power supply BTL welding, this amplifier IC peripheral is very simple to do do not do the board depends on your own conditions, the universal version is also good, the speakers are made of PVC water pipe, or you think the most suitable, the best handling of the material, the speakers I think it's still the Huivi The good, try to use the sensitivity in 92DB above, 3 to 4 inches (larger diameter bass better), impedance 4-8 ohms can be, choose the best coaxial, the cost should be able to 180, the speakers are still a little good. You can also use 2022 and other class D amplifiers, more efficient, is only able to sell the finished board, the cost will be much higher.

5 battery is only a few hundred MAH, Nanfu only 1200MAH, listening to the song is not cost-effective, if you really want to use a small volume of high effect, you can use lithium batteries, two 2400MAH-3500MAH can be, but there is no over-discharge protection circuit, the same trouble. In the circuit operating voltage, the voltage is proportional to the output power, as long as the minimum voltage to meet the circuit, the circuit can work properly, only the output power becomes smaller, but the quality of the circuit will not change,

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