Hello- I built my 2nd 5F1 that had a bit more hum than the 1st one I built, which is almost dead quite, so I've been reading on here about reducing hum in a 5F1 circuit. The only difference in the builds was that this time I used a Hammond 125DSE OT and set it up for a 5000ohm primary to 8ohm speaker,as opposed to a MOJO 10watt @ 6000ohm primary to 8ohm.
Well a lot of what I read had to do with grounding so I went and re-did the grounds. I had built it with all the grounds going to a single star ground on the chassis (with the exception of the mains and HT CT grounds which had their own each). I switched the grounding so that now the pre-amp grounds go to their own chassis point,and the power grounds go to a separate chassis point. Am I getting the star grounding idea wrong?
Now the amp sounds like a machine gun whenever I turn the vol up past 8. Is this what they call motorboating? I should have left well enough alone as the hum was pretty close to acceptable.
Well a lot of what I read had to do with grounding so I went and re-did the grounds. I had built it with all the grounds going to a single star ground on the chassis (with the exception of the mains and HT CT grounds which had their own each). I switched the grounding so that now the pre-amp grounds go to their own chassis point,and the power grounds go to a separate chassis point. Am I getting the star grounding idea wrong?
Now the amp sounds like a machine gun whenever I turn the vol up past 8. Is this what they call motorboating? I should have left well enough alone as the hum was pretty close to acceptable.
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