Power supply / noise issues

NPP

I'm having trouble with a very loud hum with certain combinations of amp, pedal and power. Before I fork out on a new power supply I'd like to get an idea of what the actual fault might be, and ask for advice on how to track it down. 

This is the situation:

Old amp: Blues jr. No trouble. New amp: 5F1 clone. Fine on its own and with some pedals but hums with others.

Pedals that work fine with the power supply include: Mooer Yellow Comp; PlimSoul; Soul Food. My TC Nova which has its own 12V power also works fine.

Pedals which produce hum with the power supply: Catalinbread 5E3 clone, Catalinbread Pareidolia. Maybe it doesn't like Catalinbread circuits?

The Pareidolia runs on a battery, and doesn't hum then. The 5E3 clone unfortunately doesn't run on a battery.

All testing was done with only one pedal between guitar and amp to rule out daisy chaining or other interference issues.

Any advice gratefully received! 

ICBM

Sounds like it might be a ground loop problem of some sort.

Is the power supply earthed? (What type of mains cable does it have, and is the earth pin on the plug metal or plastic?)

Are both amps definitely earthed correctly? (What make is the 5F1?)

crunchman

If one of the pedals is ok running on a battery then power supply would be the most obvious.  Having said that, power supply problems normally manifest when using multiple pedals together, rather than with a single one.

Other possibility is some kind of earth loop - especially if it is not doing it with the other amp.  Was the 5F1 built by someone good?  Is it earthed properly?

NPP

The power supply is not earthed, it's a continental 2-pin thing. I use it for the simple reason that I already had it before coming to the UK and didn't want to throw it away while it was working. 

The new amp is a Danplifier that was advertised on here recently. I don't have any reason to suspect that there's anything wrong with it in case Dan ( @4114Effects ;) reads this.

4114Effects

Yep, I can confirm the amp is earthed very soundly indeed :-) 

Sorry to hear it's not playing nicely with some pedals though, let me know if there's anything I can do. 

ICBM

My guess would be that it's something to do with the Catalinbread pedals, if the power supply isn't earthed (ruling out an earth loop), the amp is, and other pedals don't do it even with the same power supply and amp.

NPP

@4114Effects ; as you are also a pedal builder you may have an opinion on whether there's anything specific to Catalinbread pedals that makes them difficult, or on what power supply to get. 

I don't need all that many pedals but the 5E3 clone was my favourite overdrive and I can imagine it working well with the new amp soundwise. The PlimSoul has scratchy highs and the Soulfood doesn't really work very well with the gain up. And I'd really like to get the Pareidolia working without a battery because it complements your amp very nicely (whereas it always produced harsh mids through the Blues Jr.). 

Just to reiterate, this is not a thread on buyer's remorse. 

NPP

in case anyone is interested in the outcome of this: the culprit was, somewhat expectedly, the power supply. Last weekend I managed to dig out a spare one (it was in another country) and with that, all pedals are as quiet as mice. Problem solved. 

I also brought over the TS10 I got as a birthday present in 1985 or so and even though I've heard it said that you shouldn't pair TS-type pedals with Tweed amps because they are both mid-heavy, the sound is very pleasant, instant SRV on the neck pickup.