keychain sound mods

Amplifier circuits (even very tiny ones that run on low power) are a dime a dozen. Not clear how "access to the blob" or "access to the preamp" will help you "add sounds" to them, however. Those sounds are typically hard-coded into the chips themselves and not changable by you or anyone else here.

There ARE units that can record sounds for playback at the push of a button, but not the pre-programmed mass-market ones you are asking about.

Hi Rich,

I am hoping that just the recorded sounds are on that chip, and if i input my own line level audio signal to certain traces (or discrete components) I can get it to directly play it at higher volume... sort of like adding an auxillary jack to a stereo receiver, it bypasses the main source of the sounds (AM/FM, etc.) and just amplifies what coming in externally...

Hope that helps,

--L'ectro-- ww.dprg.org

To access the playback signal, I would suggest simply replacing the piezo speaker with a connection to a line-level amplifier input. You may need a good bit of low-pass filtering, or you may not.

Are you talking about devices that also record? In that case, find the tiny microphone, remove it, and experiment with feeding low-level audio in.

often the amplifier is on the chip.

Bye. Jasen

These things tend to be full-custom. You can't expect to generalize this kind of information across the whole class of gadgets. If you want to modify a unit, you will need to fully scope out the exact unit you want to start with. If it has a "blob" chip, it makes an sort of modification practically impossible for the average person without very specialized facilities.

Perhaps you have taken a wrong turn in attempting so solve some (unstated) objective?