Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Popsleigh on March 27, 2016, 01:08:58 pm

Title: Pots
Post by: Popsleigh on March 27, 2016, 01:08:58 pm

Hi,

am considering my first tube build. While reading and absorbing information I was left a little confused on pots. I see too the suffixes have changed.

What is the convention. Log for some applications Lin for other?

Regards

Title: Re: Pots
Post by: sluckey on March 27, 2016, 01:25:46 pm

Quote

What is the convention. Log for some applications Lin for other?

A linear taper pot changes resistance linearly, ie, same resistance change per degree of shaft rotation. Not so with a log taper pot. The first half of rotation results in very little resistance change. The last half rotation results in a lot of resistance change. Plotted out, it looks like a log graph.

The schematic should specify which taper to use. But generally, a volume pot will have a log taper. That closely corresponds to the log response curve of the human ear. The net result is that the change in volume per degree of rotation will  appear linear to the ear.

Title: Re: Pots
Post by: Popsleigh on March 27, 2016, 02:05:19 pm

Thanks