Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: isaac_teller on July 14, 2021, 07:38:46 am

Title: tremolo low frequency oscillation problem
Post by: isaac_teller on July 14, 2021, 07:38:46 am

Hello. I have a newish Fender Twin. When the tremolo is engaged there is a low frequency oscillation that increases and decreases(in speed, not frequency) with the speed knob. What could cause this and how do I fix it? Thank you.

Title: Re: tremolo low frequency oscillation problem
Post by: acheld on July 14, 2021, 09:32:16 am

From your description, it would be hard to distinguish your oscillation from the normal operation of the tremolo circuit.  (I know that is not what you trying to describe.)

Could you provide additional comments or perhaps a sound clip?

Title: Re: tremolo low frequency oscillation problem
Post by: isaac_teller on July 14, 2021, 10:26:29 am

It is a low frequency thumping even when there is no guitar signal or even no guitar plugged in.

Title: Re: tremolo low frequency oscillation problem
Post by: tubeswell on July 15, 2021, 09:32:21 am

Quote from: isaac_teller on July 14, 2021, 07:38:46 am

… newish Fender Twin…

More details please. Model number (assuming it’s a ‘Fender’) and/or schematic, gutshot (if it’s a hand wired cloney thing). There could be a multitude of reasons for the problem and without further info, we could be guessing all week.