More Pot Play

[Ric046]

Hi, I'm currently building a Ross Compressor. The 100kB pot I'm using for the volume has hardly any play. Basically I'm turning between 9-10 o'clock. Anything else is too low or too high in volume.

So far I tried substituting the 100kB for an 82k resistor and 25kB pot in series with each other. My reasoning was that with the original 100kB, the 9-10 o'clock position was roughly between 80-90k resistance over lugs 2 and 3, (lug 3 taking the signal from the circuit & lug 2 sending the signal to the output jack). Therefore the 82k would be provided at all times and the 25kB would vary the overall resistance between 82-107k and give me much more play in the volume knob, in theory. This is NOT what happen. I still can only turn between 9-10 o'clock and I don't understand why

My question is how can I get more play from my pot? And if anyone's feeling generous, what was wrong with my 82k/25kB attempt?

Cheers
Ric

[Scruffie]

Use an A100k.

[Ric046]

Cool. That would certainly shift my position from 9-10 o'clock to about 12-1 o'clock but I'm not sure if it would necessarily give me more play, as the gradient on an audio pot gets quite steep after 50% turn.

[Scruffie]

Short answer, the ear is logarithmic so the spread will seem a lot more even.

[Ric046]

OK. I'll have to stick a 100kA to see/hear what you mean!