Looking for a amplifier to connect an exciter to raspberry

Hey, for project of a friend I am looking for a small circuit or ready-made board to connect an exciter to a raspberry pi. The exciter is something like this:

It does not need to be very HiFi, just that you can understand some speech recordings, so the raspberry HiFi shield is too much already :wink:

Would something like this work? It has only 5W, but that might be enough…

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You might want to take a look at the datasheet of the tda2822m. I think 5watts is a little optimistic.

Looking at the pictures of the amplifier it’s configured in stereo. That means it can deliver 1w into an 8 ohm load at 9v power supply. This is already at 10% distortion.

It should take up to 15v power supply, though i’m not sure about the total dissipation of the ic. No values above 9v are given in the datasheet.

If you can reconfigure it to bridged mode, it can deliver 1.3w at 6v power supply.

All the above is at 1khz.

It should technically work, though i’m not sure how much power a surface transducer really needs. I’ve never used one before but i guess you’ll be pushing the amplifier pretty hard.
Also i can tell that ‘under driving’ speakers can sometimes sound pretty bad.

I would look for a different amplifier personally :slight_smile:

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Hey, thanks for the explanation! Yeah, this board is at the very low end, but in general one of these small boards from ebay/aliexpress with a bit more power could work? Any recommendation or can I just look for something with appropriate power and give it a try? The input is probably all standard line level for these boards, right?

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Yes i think you were on the right track, you just need a little more power :slight_smile:

There are integrated amplifiers in transistor style packages. I believe it’s called to-218. They look like the small power transistors but with more pins. Tda2030 comes to mind.
I believe these should be in the 5-20watt range, generally :slight_smile:

It always helps to check the datasheets, as the specs on sites like aliexpress and amazon can be a bit off :slight_smile:

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