Pedal noise

[naz420]

I'm getting a lot of noise when I plug in and in my not playing anything. Even when no pedals are engaged. What can I do to get rid of this hum . I see people with a lot of pedals in there chain how can this be done with out a ridiculous amount of hum.

[WRGKMC]

It would be allot easier to advise you if we knew what kind of pedal, amp and guitar you use. Hum has several causes and you aren't giving us much to work with.

 

The possibilities are, Bad cord, Amp grounding, tube bias, Wrong AC adaptor, poor guitar shielding, or a ground loop.

 

I'll throw the dice and say you're using a boss type pedal with the wrong adaptor. Boss type pedals are not true bypass and will remain active when bypassed. If you use an unregulated and poorly filtered AC adaptor it will hum badly whether the pedal is on or off. A cheap generic Wal-Mart style adaptor wont filter the AC properly and leave all kinds of ac ripple behind instead of pure DC voltage an it winds up getting amplified as a low level hum.

 

If you use the proper boss style Zero Hum adaptor you wont have any hum. Dan electro used to make zero hum adaptors that were inexpensive too. Most of them are 9Vdc 200~300ma. Its not just the voltage that's important its the current and how well they are filtered and regulated.

 

You can also use a multi pedal adaptor like a 1 Spot or any of the brick type which provide multiple pedals power. All should be well regulated.

 

Some pedals do require specific adaptors that provide specific voltage and currents. Using something generic can damage them. The hum that occurs is a sign the pedal isn't receiving the right voltage so you should never run them that way.

 

Other causes of hum can be cords that lack shielding or have bad grounds. Cheap cords only have 70% shielding which may be OK if you don't use pedals. If you use gain pedals you need cords that are 90% or better to minimize the noise from being amplified.

 

Fender guitars are well known for having crap shielding. They weren't designed to be gained up so all the noise could be heard. Shielding the interior from stray EMF is needed if you use high gain pedals and you want low noise.

 

Having your guitar pedals and amp on separate AC lines, having the amp plugs ground missing or bypassed can cause ground loops. Tube amps that had power tubes replaced without being rebiased can cause a steady AC hum too.

 

If you plug straight into the amp and there's no hum, then you connect the pedal and you get hum - My first suggestion abut AC hum from the adaptor is most likely. Try the pedal on a battery and it should go away, or save your money on buying that battery and just buy the right adaptor.

 

You've likely heard the term True Bypass pedals. They bypass the circuitry completely when you stomp on the switch so you wouldn't hear hum when bypassed. Boss type pedals are buffered and the signal is preamplifier even when the pedal is turned off. You can easily verify this. When you unplug the adaptor the pedal goes completely dead weather its on or off. A true bypass pedal will still pass a signal in the bypass/off mode whether it has power or not.

[daddymack]

Add to the list of hum generators: bad AC wall current, fluorescent lighting, other 'noisy'/poorly grounded electronics on the same circuit...

 

Easy questions:

1) Do you get that hum when you are plugged straight into the amp?

2) Do you get the same hum with both the Fender and Gibson guitars?

No to both? Then WRGKMC nailed it, your pedal needs a better quality AC/DC voltage converter.

Yes? Then buy an inexpensive circuit tester and make certain your AC ground is good and that your hot/neutral are not reversed.

Make sure your amp and the wall wart are on the same circuit.

Yes on the Fender, no on the Gibson? Improving the shielding may help, or putting a strat-sized humbucker in place of the single coils may help

[naz420]

Thanks for the responses. There is no hum when plugged directly into amp. It's a brand new black star ht-60 combo amp. I will have to look into these other things

[WRGKMC]

What kind of pedal is it?

[1001gear]

What are you powering the pedals with? If you aren't on an isolated power brick or batteries, you might have a grounding problem. Also related, the signal plugs might be shorting.

[Phil O'Keefe]

What pedals are you using? Are they all true bypass? If so, and if you're using a lot of them, a buffer might help.

 

[mbengs1]

remember that its normal for distortion pedals can create hum when theyre on.

[WRGKMC]

remember that its normal for distortion pedals can create hum when theyre on.

 

Common? Yes, Normal? No. Some sources of hum can be difficult to eliminate and some of it may be unavoidable due to the gear choices. Most pro musicians choose gear that minimizes the issues and also learn to reduce it well below noticeable levels.

 

With the proper cables and shielding and reasonable gain levels all you might hear is a ambient white noise created by the collision of electrons passing through layers of silicone. If you're getting hum you should buy cords with a 90+ shielding ration and work on shielding your guitar cavity better.

 

Some of it may be unavoidable if you use single coils but even there you can add dummy coils to get them to hum buck. Weeding out the culprits then finding better solutions is the name of the game. Not always easy but definitely doable. Having high quality jumpers between pedals is just as important too. Whenever possible I use these kind of jumpers to eliminate the extra wire. They make them straight and offset.

 

 

 

 

You could even convert a guitar to an active or balanced system to eliminate hum. Ever see one of these? There's a reason Les Paul built this recording guitar with balanced XLR outputs. He was big into recording and found it gave him zero hum and even ground lift options. You can do similar things with an active electronics that boost the signal way above the noise floor making hum a non issue. Its not always cheap but with most stock guitars you can easily cut the hum in half or at least well below noticeable levels.

 

[t_e_l_e]

to give any real advice to your current problem, please tell us your whole signal chain (e.g. guitar -> pedal a -> pedal b -> pedal c -> amp) and tell us how each pedal is powered. also if you use your fx loop, and if a pedal in the loop is powered from the same source as on pedal in front of your amp.

 

using one powersupply with a daisy chain can work pretty fine, but if you have one wrnog pedal in the daisy chain, or if pedals are in front of the amp and in the fx loop, noise can be really annoying...