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what transistor should I use? Answered

I'm trying to make lights for my car that pulse to the music. I've tried them out, but I have to have the music up really loud to make it work. I'm wondering what type of transistor I can use to make it more sensitive. obviously (maybe not, though, depending on your knowledge of cars), I'm using 12 volts, and line level on the stereo is 2 volts, but we need it to run with around one volt so that it doesn't get too loud.


Npn. Something similar to this may work. Resistors will need to be adjusted for correct voltages. Correct me anyone if this won't work.


Put a 1K-4.7k resistor in series with the base. The LEDs ARE the output. Put them in series with the collector, remove the 1.5k and see what happens.

Darlington pair modification on what you have? L

honestly, it's not so much the kind of transistor in most cases, it's the amount of gain used to amplify the input signal. In general, it sounds like you need to increase the gain (amplification) by at least a factor of 2- 4 on your circuit in order to bring the working range into "view" If that is mumbo jumbo, can you post the schematic or the portion that contains the amplifier/discriminator so that it can be better evaluated?? If not,. I think you see where I'm headed.

how about a cheap 20 - 40 watt amp just for the lights. That way you could run the sound the way you wanted it and adjust for the lights seperately.