control Stereo Volume

I have an old style Cassette SONY x-plod car audio stereo player for car. i have removed main cassette section & replaced it with an USB MP3/FM board with remote control. I made this because i believe in SONY's amplifier so successfully tracked amp track to get source from USB board.

But here i got a problem with board which forgets volume level & restores to 25 level(Default range 0 to 50 level). so volume is boosting at high at every start of player. Now i want to Analog stereo volume controller between USB board's output & SONY amplifier's input.

so what should be the configuration for volume controller??? Output target for amplifier is 4speaker(2x150Watts[Front] & 2x180Watts[Rear]).

Does my idea works?? if it works what is the configuration for Analog stereo volume controller.??

Picture of control Stereo Volume
2013-03-26 09.33.51.jpg
chinnuabhi (author) 4 years ago
Fixed with 47K stereo analog potentiometer
I think the usual trick for attenuating (making smaller) a line level analog audio signal is to run each channel through a potentiometer, one for each channel.

There exists a gizmo made to do exactly this for a pair of headphones.  It is probably called a "in line volume control for headphones", or something like that.  Inside it has two tiny little potentiometers, one for the left channel and one for the right, and typically both those pots are connected to the same wheel, and the wheel is made to be turned with your thumb.

A picture of one of these "volume control for headphones" gizmos is attached.  Also a circuit diagram of what I think it looks like inside.  The dotted line in that circuit labeled "Dual-Gang Volume Control" indicates two pots mechanically linked so they turn together.    Both of these pictures were found by me using Google(r) images.

I am guessing the output from your player board is low powered, is line level, so that you could comfortably run it through such a "volume control for headphones", without it hurting the tiny little potentiometers.

However it seems to me somewhat  kludgy to have to turn a little knob every time you want to turn on your car stereo.

Another possibility might be if there were some way to somehow keep your player board powered all the time, so that way it will not "forget" its settings.

chinnuabhi (author)  Jack A Lopez4 years ago
Thanx for Answer but i already had bit similar idea.

I need specific values for potentiometer which is compatiable for proper output.
Try 50K log track.