Sound to L.E.D strip pre-amp

266

04:16:29

Just a quick circuit I was working on and testing with an led before I finish it off with an rgb strip. I used the a 3.5 mm jack as my input and got the led to flash to whatever the input was. The problem in trying to solve right now is that if the volume is increased, the op amp cuts the signal and it also seems as if the led remains on all the time because of this. I was thinking of using the input signal to vary the gain of the op amp so that if the volume is increased, then the gain would somehow remain the same as it was before the volume change. Any ideas on how to do this or any other methods of achieving this? Also, I'll update a new circuit once I get this all working so that everyone can have a sound "viewing" rgb led strip 👍

published 8 years ago

rich11292000

8 years ago

Maybe your transistor melted

x35m95

8 years ago

Tried it with another one(Tip120 btw, thats what i had) before because i thought i had a bad one and it did the same, also tried it with a FET and it did the same thing, just at full brightness

rich11292000

8 years ago

Maybe your opamp fried. Do you think you need a base resistor?

2ctiby

8 years ago

http://everycircuit.com/circuit/5704067075801088

x35m95

8 years ago

@rich11292000 The op amp was fine, i tried it with another and i tried with the base resitor and the same happened.

x35m95

8 years ago

@2ctiby Ill give it a try later, thanks

2ctiby

8 years ago

Adjusted 2 version to try here... this may work if your individual Mosfet parameters are very different than the earlier Mosfet settings http://everycircuit.com/circuit/5713056381534208

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