What's causing the ugly noises?

  • Thread starter Thread starter thebigcheese
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thebigcheese

thebigcheese

"Hi, I'm in Delaware."
Ok, that's sort of misleading because I have a general idea, but I'm hoping someone here will be able to give me a good idea where to start looking. Today I was playing with my new amp, a Blues Jr., and I noticed this ugly noise, like a high-pitched ringing, that was going on. After a while, I decided to blame my pedals and tried running the guitar straight in. It's definitely something having to do with the pedals. Right now, my pedals are setup like so: Whammy (with it's own power supply)->DF-7->Phaser->Tremolo->DigiDelay (all of those on a cheapo Danelectro power supply that came with some cheapo pedals). What would be causing the noise? Is it the way the power supply is set up, or should I look at individual pedals?

The other noise that's bugging me is a metallic rattling that only happens when I hit the low G on my guitar. I tried pinpointing if it was coming from the reverb unit or the amp circuitry, but when I put my ear near the reverb thing, the bass from the amp hurts me ear. I think I can literally feel my eardrum vibrating. So the rattling seems louder near the circuitry, but it could just be that my eardrum dying mutes it when I try to listen elsewhere. Any ideas where I might start looking?
 
Check the polarity requirements for your pedals, they might be different from one another - I tried to power a Dunlop wah with a Boss PSA and got a squealing feedback noise; different polarity required.

As for the amp, don't put your ear near it! I had a similar problem with a Marshall TSL, it was a sympatehtic vibaration upsetting something wihin the reverb tank. I'd start by tightening all the screws that you can, but be careful! Tube amp caps can store lethal charges.
 
Check the polarity requirements for your pedals, they might be different from one another - I tried to power a Dunlop wah with a Boss PSA and got a squealing feedback noise; different polarity required.

As for the amp, don't put your ear near it! I had a similar problem with a Marshall TSL, it was a sympatehtic vibaration upsetting something wihin the reverb tank. I'd start by tightening all the screws that you can, but be careful! Tube amp caps can store lethal charges.
It's not the polarity. I made that mistake once, so I know what that sounds like. I'm pretty sure I'm overloading the power supply, since it only outputs 200 mA, but I'm a little unclear on how all the conversion goes b/c all the Digitech pedals (everything except the tremolo) take in 4.8 watts. Ugh. The tremolo is a BYOC kit, so I'm not really sure what it takes. If I am overdrawing, would that be causing the noise, or would they just not work?
 
On the upside, I figured out what the rattling is, just not how to fix it yet. There's are two springs attached to a metal thing under two of the tubes (the preamp tubes, I think) and one of the springs is resting up against one of the tubes. It goes haywire when you hit the right note and buzzes against the tube. Given that tubes get pretty hot and I'm not entirely sure what this spring does, though, I'm not really sure how to fix the problem yet... but at least now I know where all the rattling is happening, so I can potentially fix it all.
 
It sounds like the pedals are starved for current-200 ma isn't nearly enough for the pedals you are running-if I am correctly understanding your setup.
Is it a reverb spring that you are talking about, causing the racket?
 
It sounds like the pedals are starved for current-200 ma isn't nearly enough for the pedals you are running-if I am correctly understanding your setup.
Is it a reverb spring that you are talking about, causing the racket?
No, the two springs hold up a piece of metal that goes under two of the tubes as if to hold them in place (except that they stay in place anyway). I discovered that I can actually just rotate the spring to get it out of the way, so that's taken care of now.

Would being starved for power actually create the whining noise? Also, I noticed that there are 9v power supplies and 9.6v power supplies. Digitech says to get a 9.6v one for the pedals, even though they can take 9v batteries, so I'm a little confused about what I'm supposed to get... Also, how do I figure out how much current my pedals are drawing? The only thing they tell me in the manual is that they draw 4.8 watts, which isn't very helpful when all the power supplies list mA. I tried a conversion formula I found and that resulted in each pedal drawing 500 mA, even though I've heard that they normally draw 250 mA. And I still don't know what my tremolo draws... all this electronics stuff is confusing to me...

Edit: Maybe someone can recommend me a good power solution. I would love to only have to use up one outlet for all my pedals. I have those that I mentioned and also a Rocktron Banshee that uses the same kind of power supply as the Whammy, which is apparently not the same as the other pedals. The smaller pedals all seem to work with a 9.6v supply, while the bigger two work with a 9v supply (and maybe the opposite polarity, too; the plug is a slightly different size, anyway).
 
So I got one of those 1-spot thingies. The pedals all worked before and they all still work now, but I was still getting the annoying whistling noise. I went through and unplugged my pedals one by one and it seems like it was the Hyperphase causing the problem. I took it out of the chain and the problem seems to be gone now, though I am still getting minor amounts of hissy staticiness (more noise than if there were no pedals plugged in, I mean), probably a result of the Digitech pedals not having true bypass (though I could be mistaken about that). Luckily, I never used the Hyperphase for anything.
 
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