wiring from OT to power tubes

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wiring from OT to power tubes

Post by Bieworm »

is there any impact on sound or noise when the blue and brown wire from the output transformer to pin 7 on V4 and 5 are switched?
I read that this sometimes is a remedy for eliminating noise. Is that only squeal noise or is this also for other noises? Is it of importance which phase is going to V4 or 5? And if so..why?

It's for the 18W TMB..
I ask this because I noticed that on my 18W classic the brown wire goes to V4 and blue to V5, while on my TMB I did the opposite. I think this is only of importance in case of a NFB loop or presence control...but I might be wrong.

THX , Bjorn
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Re: wiring from OT to power tubes

Post by JMPGuitars »

Ideally the brown wire goes to the higher valve number, but you're correct. It usually only matters when a Negative feedback loop is used.
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