[2435] Hum, Whine and Noise

Date: October 10th, 2018 | Comments : [1] | Categories: DIY.

I often see people post that their pedal is making a noise, but they fail to describe the sound adequately to allow anyone to decipher the cause. For example, a hum is low pitched and is often caused by a poor ground connection or bad cables. A hum sounds like this (you may need to turn down the volume):



A noise caused by power supply aliasing, as from a poorly designed charge pump, or from radio frequency interference will be higher in pitch and often sounds like this:



Another common noise is a random background hiss. All electronic components generate a very small noise voltage and high gain circuits can make the sound much more prominent, like this:



Recognizing the type of noise your pedal is producing is the first step to working out a solution to the problem!


One Response to “Hum, Whine and Noise”

[786412] pink jimi photon Says: 10:48 pm, May 23rd, 2019

hi jack,
as usual, great posting.
the final example at least may be helped by a bigish cap… say 100n or so to ground.
a lot of times, stuff just needs decoupling, i guess 😉
all the best bro


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