12v transformer for relays

[Enzo]

Didn't we determine earlier that if you turned the guitar down the hum went away? Refer to posts #32 and #33 That meaning the guitar was picking up the hum. if you can turn the guitar volume control to zero and the noise stops, the noise is not from the amp. And that would rule out the pedals as well. You can look all you want in the amp or your pedals and you won;t find a problem that is in your guitar.

Why does it wait until second set? becasue that is about the time the heavy air conditioning starts to work, the walk-in coolers start to work because the doors are opening a lot, the compressors on various stuff are working, and who knows how balanced the mains power is at the gig. You think your amp is any less warm when you run it at home where it doesn't hum. Also could be that by second set they have dialed the house lights down and the dimmers are radiating hum. believe me that is nothning new.

Why does it happen in the OD channel more than the clean? The OD channel has more gain, so it amplifies noise more, just as it amplifies your guitar more. That is why OD chanels hiss more than clean channels.

Popping - do you have the reverse diode across the relay coil or not?


And when it comes to hanging resistors, you have to do them all as required for results. You can;t try them one at a time

[lowell]

Enzo,
No we determined in previous posts that the hum did not go away when guitar volume was turned down. It did however go away when input to the amp was removed. It's now quite obvious to me that it's one of my pedals if removing the input rids of it but the guitars volume does not, as the guitar is before all my pedals obviously. And it has happened at 2 different venues which I play at weekly, and this never happened w/ previous amps, leaving it very unlikely it's the venue's power, though I know that can be a problem sometimes. I think it's my 70's Maestro phase shifter which has an AC plug and no external step-down transformer. That pedal has caused other pops and hum in the past so it's very likely to be the culprit of all this.

Oh I will be sure to try all the 1m's at once instead of 1 at a time. I'm actually blown away by how minimal the popping is now after moving those caps and leaving the OD channel input on at all times. Thanks Defaced.

Oh and yes I have the reverse diodes on both relays and they are correct polarity. Thanks for your help Enzo.

[Enzo]

Ah, detail I missed then. Sounds like you are right.

If you have seen improvement moving the caps, then you can see how much difference it makes. The devil is in the details, as they say. Just keep an eye for any cap that would be made to change the voltage across it when switched.

[lowell]

Damned phase shifter... was definitely problem. Time and time again I get fooled by simple fixes, things I should check for just to rule them out. Well, keeping educated I guess is one way to look at it.

Now on to adding some warmth to and tweaking the OD channel.

[defaced]

Cool. Glad to see you got it fixed.