LM3886 volume pot

[dr.power]

Hello guys,

I have amde a power amplifier based up on LM3886.

Unfortunetely the input signal decrases when I put a 10K pot for the level control at the input of the chip per datsheet.
Whats wrong here? Is that due to impedance of the input signal?

the other question is that The sound decrases/incrases in level just by small turns of the volum. How can I correct this problem?

Thanks a lot

 

[gary350]

Defective 10K variable resistor. Test your variable resistor with your ohm meter.

Put a .01 uf cap on the input before the 10k resistor.

 

[audioguru]

What is your signal source that is reduced when it has a 10k load? Maybe your 10k pot is actually a much lower resistance. Measure it.

A trimmer pot has a linear taper. But a volume control has an audio taper (logarithmic) so that when it is turned down to half then the level is reduced to 1/10th that sounds half as loud. When a linear taper pot is turned down to half then the loudness is reduced only a little.