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tube preamp makes rushing noise at speakers
tube preamp makes rushing noise at speakers
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Old 2nd November 2020, 04:54 AM   #1
gregas is offline gregas  Canada
diyAudio Member
Join Date: Nov 2018
Location: Toronto
Default tube preamp makes rushing noise at speakers

Hey guys,

I've been working on this tube preamp build for a few months now, with the help of a friend. I finally finished it and noticed a rushing noise coming out of the speakers. We haven't been able to figure out how to get rid of the noise.
The noise seems to be coming from the mosfets. I double checked the vero board where the mosfets are but i don't see any mistakes. I also checked to make sure the zeners are orientated correctly and they are. The mosfets make noise with nothing connected to the gates. I.E. when the 6SN7ís have been pulled so that only the B+ is present. I've pasted the schematic hopefully you guys can see it. Does anyone have any advice?