Go Down

Topic: Amplify toy speaker output with LM386 (Read 2715 times) previous topic - next topic

ifugaopapercraft

My project involves sounds from boards salvaged from children's toys running at 3v~5v. These need to be much louder. I have built a circuit with LM386 (http://www.learningaboutelectronics.com/Articles/How-to-connect-a-LM386-audio-amplifier-chip) without success. I assumed that audio input was from the +/- speaker wires of the toy to the 386. Is this correct?

Grumpy_Mike

That is correct, however you may want to couple into the input through a capacitor to remove ant DC on the input signal.

ifugaopapercraft

Thanks for the advise. To be sure I understand correctly, should a cap be placed across pos to neg of these two wires from the toy board speaker to the 386 amp circuit.  Also, should the grounds of the two (toy and amp) be joined, or is this already happening with the ground speaker wire when connected to the amp circuit? 

Grumpy_Mike

No the c should be in seriese with a speaker lead.
The -ve speaker should be ground. If it is not then connect the grounds together and have another c in the -ve input as well.

Go Up
 


Please enter a valid email to subscribe

Confirm your email address

We need to confirm your email address.
To complete the subscription, please click the link in the email we just sent you.

Thank you for subscribing!

Arduino
via Egeo 16
Torino, 10131
Italy