Guitar pedal hiss (and hum) -- is it time for a better source of power?

Should have mentioned that this noise is with all pedals turned off.

Noise comes from a variety of sources.

Poor connections or cheap cables let the hum in.

Using the wrong type of power source also lets noise in. I rarely ever used any sort of pedals but when I did, if they were on a wall wart they had noise, but on battery they were perfectly quiet.

All electronic circuits create their own internal noise. The cheaper the circuit design the more noise you are likely to hear. For stage/live use, this is usually not a problem, but in a studio it's not acceptable.

10 pedals.... wow.... that's alot of stuff that could be causing it.

Be a detective.... go back to a straight guitar cord... if it's quiet, add one pedal on the power supply. Check the sound to see if it's quiet. If yes, proceed, if not swap to a different pedal until you have a quiet signal. If no.... swap to battery power to check noise.  

Then before plugging any more pedals into the sound chain, plug them all in, one by one to be sure the load on the supply is not causing the noise.

Assuming you have quiet, add the pedals one by one, until you find the offending one. You could have one that has gone bad or has a loose connection in it.

on power supplies: batteries put out an even DC voltage so on them, you should have little noise caused by the power supply.  The wall warts and other power supplies take the AC voltage and convert it to DC and filter it to smooth it out. All AC to DC supply will have a "ripple voltage" and depending on the level of that, will cause noise and hum. I work from time to time with intercom systems and once I tried to save over a hundred bucks on a power supply. Installing a cheaper DC supply resulted in massive hum. Battery power, it was totally quiet, so I ended up buying the correct supply and it worked perfectly. So the supply could very well be the problem.


Play detective and try to isolate the noise...see if it comes from one or more of the pedals. Good luck.

To reiterate what Hacker is saying... I firmly believe that any quality you might hope for with any sound circuit starts with the power supply. The circumstance of music gear distribution is that if you shop for gear with a good power supply the good sound circuit comes along for the ride. Lots of 'sumer gear has a good sound circuit design that is being ruined by a marginal power supply.

I tried several cheaper power supplies because I use a lot of pedals when I use pedals. It's fun.

I just couldn't justify keeping batteries in everything... even though that's what sounds the best.

The VoodooLabs was the cheapest one that eliminated problems CAUSED by the power supply. They are not the only ones making such a nice supply but theirs is easily available.

Hidden in the history of sound circuit design is the origin of the term "B+"... the earliest amps used Batteries for DC voltage because the other options were just too noisy. Now we use highly rectified power supplies with lots of filtering and still call the power rails B+.

:-)

Good stuff!

The culprit seems to be my Electro Harmonix Cathedral reverb. If I remove it, the whining sound goes away. The overall noise is louder than when I am plugged strait into the amp, but I guess that is to be expected.

I think I may be grab a voodoo labs pedal power anyway to see if I can bring the overall noise level down a touch. I'm using some wall warts that are of questionable quality.

Anyone have any opinions on running pedals at different voltages? I have a couple of pedals that will accept 18v as well as 9. Is this worth doing or is a golden eared delusion?

I've had some Electro Harmonix stuff in the past and it was noisy. If it is turned up for high gain mode..... the noise will be even greater.

Also remember that when you have 10 pedals in series, all that noise (even though individually they are quiet) gets added together.

Just a side story: I bought and used a "Hot Tubes" distortion pedal for a number of years. Then stored it away for even more. When I pulled it out again and tested it, well, it worked fine but I didn't remember it being that noisy. I sold it on eBay with the warning that it was noisy. Some body bid it up to more than the thing cost me new, and when they got it....raved about how good it sounded. Glad they liked it, because it was a nice sounding pedal.... noisy but nice... since I had a Boogie, I didn't figure I would ever use it again and became a straight cord purist.