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Is there a method available to help differentiate notes on a wide variety of electronic noise sounds (not-quite white/pink noise, heavy buzzing, fuzz, etc.)?

I've taken on an odd project where I am trying to get the pitch of sounds that are not generally particularly musical to try and make something out of it. They are electronically generated from very old computer hardware (old Atari POKEY, if anybody cares). However, the software/devices I have been trying to use fails to pick up notes on so much of the sounds produced, even though I can clearly hear a "note" in the sound. I can hum along and tune that, but I want to chart them to +/- 2 cent accuracy if at all possible, and I am not pitch perfect myself.

Using tuners have not been very successful. I have tried:

FMIT (Free Music Instrument Tuner) for Windows -- has a few options to control the pick up, but many sounds get nothing or jump all over the place

ReaTune for Reaper DAW -- I cannot get this to pick up anything meaningful

Various Snark instrument tuners that I have -- Holding these up to the speakers does nothing, regardless of the volume of the output

Are there methods to help figure out the pitch/frequency that noise is making?

Here are some samples (in WAV, so they are ~1-3MB) that I sustain for a moment, then start changing the pitch to make it obvious:

"White Noise" - I'd be surprised if much can be found here, but I'm asking anyways:

http://junk.zolaerla.com/Media/Stack/Distort0.wav

http://junk.zolaerla.com/Media/Stack/Distort0-Poly9.wav

Buzzy, almost engine-like sounds:

http://junk.zolaerla.com/Media/Stack/Distort4-64.wav

http://junk.zolaerla.com/Media/Stack/Distort4-15-ch0.wav

http://junk.zolaerla.com/Media/Stack/Distort4-15-ch2.wav

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  • Welcome! I'm afraid requests for recommendations are not one of the topics covered here. But I suggest you experiment with the idea of filters, especially "band pass" filters. It's the idea that you're letting certain frequencies through and suppressing others. Make that range narrow enough and you'll emphasize a particular "note." You can experiment with this idea in lots of DAWs, from Audacity to non-free software, or with old-school hardware. Commented Feb 6, 2023 at 22:26
  • (Meanwhile, if the task giving you difficulty is simply identifying a pitch, don't overthink it: if you can perceive an overall pitch, just compare it to another source like a piano until you figure out what pitch it is.) Commented Feb 6, 2023 at 22:28
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    The issue is that questions of the form "please recommend an app for ___" or "what's the best ___" are not covered. If you search in the Meta section you can find some of the arguments that led to that decision; it includes reasons like recommendations becoming outdated quickly, a lack of a "correct answer," etc. Nothing stopping us from giving our opinions in the comments, though; mine is "using a tool to identify pitches is always going to be difficult." Especially if the sound source is not just one discrete pitch, or has a complicated waveform. Much easier just to do it "by ear" Commented Feb 6, 2023 at 22:39
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    Compulsory floppotron link - youtube.com/watch?v=Oym7B7YidKs ;))
    – Tetsujin
    Commented Feb 7, 2023 at 8:33
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    Samples of the actual sounds would be really helpful
    – ojs
    Commented Feb 7, 2023 at 8:51

2 Answers 2

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Some sounds do have pitch, some don't. In general, pitched sounds will have strong discrete sine components, following harmonic series, while unpitched ones will have continuous spectrum and nonharmonic relations between frequencies, but there is no clear boundary. Pitch belongs to psychoacoustics, not math or physics.

You can try to look at the frequency spectrum of a sound (e.g., using free audacity), and see if there is any dominant frequency in the sound. However, in the end, it's only your ear which can tell you if a sound does have a pitch and what is it.

Here are some examples of synthesizing sounds with a perceivable pitch by applying frequency filters.

  1. Note how the sound gradually changes from unpitched to pitched when the filter strength is increased (3:28–3:59):

  1. Note how the tone changes between two series of examples with broader and narrower filter frequency range. If you tried to increase the filter width more, the pitch would become gradually less apparent (0:11–0:31):

  1. Note how the sound containing multiple frequencies might be perceived as a single sound, or a chord (2:54–3:26):

You can perform similar experiments with audacity or other free software.

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Note: The original question asked for detecting a pitch in a pure noise signal. This is what this answer refers to.

Noise is actually a random waveform. In order to perceive a signal as a specific note (pitch) the waveform has to be periodic, which is not random. Therefore noise cannot have a defined pitch by definition. If a sound has a pitch it is not noise.

You can also go the opposite way and use a synthesizer software like amsyth to produce a noise at a specific pitch. You will hear no differences in sound regardless of note you use to produce the sound. An A will sound the same as a C or a Bb or anything else.

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    This isn't purely white noise. It's generated by hardware and allows changing a divisor value that very clearly modifies the sound. What I was calling white noise SOUNDS like TV static, but you can make it sound higher or lower pitch by changing the divisor value. Commented Feb 7, 2023 at 3:06

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