# Mathematically come up with EQ frequencies for specific notes

Let’s say I have a sample sampled at C-4. I play melodies with the white keys only, so CDEFGAB.

I would like to find out a way of mathematically going: “OK, these are the frequencies for each octave of CDEFGAB” - and boosting those frequencies with an EQ plugin (EQ8? FabFilter Pro-Q?). Or: alternatively, kill the frequencies that are C# D# F# G# A#.

How would I go about doing this kind of “cleaning up” frequencies of a sample?

I’m thinking “select the contents of a channel, press a key -> EQ8/Pro-Q boosts the frequencies I play at, and kills the frequencies I’m not playing at”.

Any ideas how to go about doing that?

https://pages.mtu.edu/~suits/NoteFreqCalcs.html
If you’re doing it manually, a frequency chart is quicker: https://pages.mtu.edu/~suits/notefreqs.html

What you essentially will be doing is to boost/attenuate the fundamental frequency of the sound.

I’ve experimented with notch filtering out all non-diatonic frequencies of a song. It did bring some kind of flavour, perhaps even subtle increase of clarity, but I’m not sure if it’s technically recommended. Filters will add phase shifting, and I theorize that non-diatonic overtones gives a sound some amplitude at spots that are less likely to clash with other notes/instruments.

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Doing it programatically would allow you to automate an EQ based on notes on the pattern.

I suspect that hard-coding a lookup table would be better than calculating them each time (though memoization would help).

But it could make for an interesting tool (e.g. allow it to EQ not just the given note but offsets as well)

You can check out the tuned devices. There is a keytracked filter there.

TheBellows and ZeroFly seem to have tuned the EQ as well. [2.7] More Tuned Devices!

(oops… 404)

Are you thinking of my 96 Band EQ doofer perhaps? It has one slider for every note frequenzy across 8 octaves.
96 Band EQ.xrdp (351.8 KB)

will it work on Renoise3.1? I’m stuck in (== I’ve had to downgrade to) Renoise3.1-town, because of it supporting 32-bit plugins.

Yeah I made a formula that will let you control the frequency of an EQ tap with the keytracker.

ktrk eq.xrdp (13.3 KB)

Hi. I’m new but I did come up with a basic system of calculating note frequencies with a 99.20% or greater accuracy using third grade math. For comparison, it’s usually more accurate than manually sweeping bands in a GUI. It’s called the F350 Method and you can see it here:

Chart at 6:53
Hope that helps.

Hexspa

I though i remember @taktik posted a link to backups of the Download section somewhere, or was it a dream? I’d definately like to find it if it exists.

esaruoho: it’s made in 3.1 i think, or was it 3.0?