Need help identifying an amplifier

Hello All!

So long story short, my friend has this voice-changer toy that he bought that contains a small speaker. We'd like to put a larger speaker on it. Is it possible to just wire the speaker to the old board, or do I need an amplifier in between? And if so, I have a toy guitar amplifier that I've posted a photo of below (both sides of the circuit board). Would I be able to use this as the amplifier (and use its speaker), and if so, where can I attach sound changer to this board? Many thanks for the help, I love this forum!

-Tom


you can probably just attach the larger speaker, but it might not be that much louder. give it a try and see how it sounds.

what is the toy amplifier meant to amplify? is there an input jack of any kind on it?

http://www.mpja.com/4-Ohm-Mini-Speaker/productinfo/14618%20SP/
This one is efficient (high sensitivity) and has good sound.
It is 4 ohm vs 8 ohm, get 2 and wire them in series.

The amplifier was used for a shirt guitar toy (link http://www.thinkgeek.com/product/ded2/). There are 8 pins on the toy amp that connected to the shirt, probably connected to the buttons on the shirt, so I don't think those 8 pins apply to any sound functions. The amp itself doesn't have an input jack, but does have an output jack, so I'm stuck there. It's sort of a miniature guitar amp, just without the normal input for the guitar. Any help / advice would be appreciated. I'm going to try just attaching the larger speaker in a little bit, and I'll let you know how it goes. Thanks again to the two of you for the advice!

it probably generates its own audio onboard, and therefore doesnt have an input. it looks like the chip in the upper right hand corner is the amplifier. c8 might be the input coupling capacitor.

Thank you for the reply! If you don’t mind my asking, what is the coupling capacitor? And would I be able to wire the voice transformer to this chip? You’re brilliant!

oops, i meant c20.

you can try sending the signal in there. just cut the trace thats coming from dual pot. what is the part number on u8. that might help figure out if its actually the amp chip, and which pins are which.

The chip is an XPT4871, which after googling, you're right, is the amplifier. So, which pin on this would I connect to? And thank you again for the help.

awesome. c20 is the input. just cut the trace, and solder to the end of c20 facing away from the chip.