cut control question

General discussion area for tube amps.

Moderators: pompeiisneaks, Colossal

Post Reply
wsaraceni
Posts: 517
Joined: Fri Apr 14, 2006 5:18 pm

cut control question

Post by wsaraceni »

sometimes the capacitor connects to the middle leg of the POT. sometimes it connects to the opposite leg to the other lead. what purpose does that serve?
User avatar
Super_Reverb
Posts: 188
Joined: Tue Dec 21, 2010 6:28 am
Location: Indianapolis, USA

Re: cut control question

Post by Super_Reverb »

Two ways you can connect your variable resistor on a cut control.

A cut control is adding a high frequency corner based on f=1/(2*pi*R*C) To control the corner frequency, you are varying the resistor value, so you have to connect between one end of the resistor and the wiper (center lug on most pots)

You can also short one end of the pot to the wiper and connect the two terminal variable resistor, you just created, in series with the cap.

Difference between the two is: in #2, you are shorting the "unused" portion of the pot. Do you care? The cut control doesn't care.

Strictly speaking, pots are three terminal variable resistors used as a variable voltage divider and a rheostat is a two terminal variable resistor, so in the case of a HF cut control or as part of some tonestacks, the variable resistors (pots) are being used as rheostats.


rob
Post Reply