Battery powered Mono Amp reccomendation?

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Hello,

I am looking to find a small chip amp board that can be powered by a not-so-large battery pack, and can drive a midrange compression driver.

The compression driver will likely be a 40W 16 ohm unit:

http://www.newark.com/mcm/54-050/compression-horn-driver-40w-rms/dp/39C0599

Alternatively I may use this 150W 8 ohm driver:

Selenium D250-X GW 1" Phenolic Horn Driver 1-3/8"-18 TPI

The 150W 8ohm driver I have already tested on smallish stereo chip amps like the Dayton DTA-1 and a HifimeDIY T2. . . the T2 was probably pushing around 40W and I was getting a decent enough response for my purpose.

The battery I will use will need to be mounted along with the compression driver & amplifier on the body of a dancer. . . so it can't be too excessively large. I will need to get ~2hrs of charge before the battery needs to be recharged.

Can anyone recommend a low power monophonic amplifier board that would suit this purpose? Anything under $100USD should be fine. To be clear, I am not looking for super high fidelity. The compression driver has limited frequency response (100hz-8khz), and will only be outputting (processed) voice signals. That said, I require a reliable product.

I was thinking perhaps this Sure "100w TPA3116" might be okay. It claims 100W @ 2ohms. I have no idea what that would be @ 16ohms---maybe around 35-40W?

Sure Electronics' webstore 1 x 100 Watt Class D Audio Amplifier Board -TPA3116

If you have any suggestions on suitable battery packs, I would be interested in that too.

Many thanks for any help !
 

PRR

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Joined 2003
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100W@ 2 Ohms may be 13 Watts @ 16 Ohms.

You do not mention a horn. Without a horn a compression driver is a cripple. Yes, I have got residential levels out of a much larger driver naked, but that little 1" won't have much below 2KHz.

When size/weight is a limit, a simple cone speaker is usually a better fit.

With a horn, 40 Watts for 2 hours will be permanent hearing damage. (Though I shudder to think of the body damage, dancing 2 hours with a worthwhile horn strap-on.)

Generally, battery life depends on a GOOD estimate of the maximum power truly needed. With class AB amps this is essential, because their efficiency falls-off so very rapidly below max output. With class D the tradeoff is not so severe, but you still do not want to carry excess power/energy.

If the dance is all in one room, you can do much with a 1W on the nominal source, and a 100W amp off-stage delayed 30mS. Your ear goes to the First Arrival, not the loudest source, over a significant range of arrival times and power levels.
 
100W@ 2 Ohms may be 13 Watts @ 16 Ohms.

You do not mention a horn. . .


Thanks for your comments!

Do you know what the rough calculation is to determine how many watts an amp rated for 100W @ 2ohms will provide at 16ohms? If I want to reach up to 40W peak @ 16 ohms. . .what mono amp should I be looking for? It seems Sure rates everything @ 2ohm or 3ohm. . . maybe a 300W @ 3ohm amp would work?

You do not mention a horn. . .


Yes I was not very specific. I am building a kind of body mounted talkbox. . . so the driver outputs to a plastic tube which passes to the performers mouth, and transforms the mouth into a horn. Source signals are strictly processed voice. . . so a frequency response from ~400hz->3khz is workable in this case.

I have tried sticking actual speakers (piezoelectric) in the mouth to achieve a similar effect, but the only speaker I could fit into the dancer's mouth without causing a great deal of discomfort is decidedly too quiet for my purpose.

The amp/battery/driver need to be body mounted because the performance unfolds across multiple rooms (& separate spaces in a city).

Thanks !
pvh
 
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