11-05-2014, 07:48 PM
I've been noticing a slight little buzz with each note on my V4. I mentioned in another thread my rocker switches were a little dirty/stiff. I was getting some increased noise/note interference when using the Treble rocker on the "+" position. I thought cleaning might help but that didn't.
The issue is still there (regarding the Treble rocker) and I'm wondering if the issue with the rocker and the general buzzing are related. To clarify, when I take the Treble rocker off the + position, part of the issue is resolved, but the general buzzing on each note - mostly bass notes is there.
I thought it might be a amp vibration issue. I brought the V4 home and put it on my bench, running it into a small speaker for testing and even at low volumes, the issue still occurs.
I took a chop stick and tapped the preamp tubes and V2 seemed like it might be microphonic - it was making a little noise audible through the amp when I tapped it.
I replaced it with a fresh JJ 12AX7 I had. I tapped around again, also on the top of the PCB and around R19/V3, I'm getting some amplification of my tapping into the amp. Its not loud, but its occurring; I'm not sure if that is a bad thing.
With regard to the Treble rocker. Is the noise likely mechanical, i.e. the switch, or something on the control PCB?
All the preamp tubes have been replaced, minus the 6K11. which is either the original, or certainly old.
The issue is still there (regarding the Treble rocker) and I'm wondering if the issue with the rocker and the general buzzing are related. To clarify, when I take the Treble rocker off the + position, part of the issue is resolved, but the general buzzing on each note - mostly bass notes is there.
I thought it might be a amp vibration issue. I brought the V4 home and put it on my bench, running it into a small speaker for testing and even at low volumes, the issue still occurs.
I took a chop stick and tapped the preamp tubes and V2 seemed like it might be microphonic - it was making a little noise audible through the amp when I tapped it.
I replaced it with a fresh JJ 12AX7 I had. I tapped around again, also on the top of the PCB and around R19/V3, I'm getting some amplification of my tapping into the amp. Its not loud, but its occurring; I'm not sure if that is a bad thing.
With regard to the Treble rocker. Is the noise likely mechanical, i.e. the switch, or something on the control PCB?
All the preamp tubes have been replaced, minus the 6K11. which is either the original, or certainly old.