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previous: KB Is the pot grounded ?,KB... -- 10/17/2004 2:23 PM View Thread

Re: help with buzz

10/17/2004 4:08 PM
Re: help with buzz
Rewire those heaters. Twist the wires and keep them away from any signal wires, especially the grids, pins 2 and 7 on the 12AX7. The symptoms you described suggest the output of the pot is running too close to one of the heater wires. Replacing that wire with coax grounded at one end should help. Also, check that the heater supply is grounded either through a center tap, artificial center tap (two 100 ohm resistors) or hum-balance pot.

drewl heater supply is -- 10/18/2004 6:17 PM