Download: aMg-zPianoRainbowV1.zip
7 colors for each notes, beginning with lowest vibration color and beginning octave, Red = C and so forth. A system I use for notation color coding them.

So I toyed around with this, it works at 16hz, 250hz and the above steps that is available as per now for the beginning of the frequency, 500, 1k and 2khz. Like 30hz is very close but just off a note, 32hz should fix that, or 33hz - 32hz seems better to the eyes. 60hz is also very close, one note off as well. Like if you do not have a bigger reason to use 30 and 60hz, then an update them to 32 and 64hz would be nice, and maybe upgrade the 100hz for 128hz as well. At least if there is no bigger reason for you choosing those specific numbers, it would help this Gradient work in those levels.

Actually: 16hz, 32hz, 64hz, 128hz, 256hz, 512hz - would not look bad as options, keeping them to C, pretty much. Still a little off I guess but it looks the best, and less off then what is there already.

Note | Frequency
C₀ | 16.35 Hz
C₁ | 32.70 Hz
C₂ | 65.41 Hz
C₃ | 130.81 Hz
C₄ | 261.63 Hz (Middle C)

Anyway, here is a picture of it running in 16hz:

250hz:

Of cause there are other settings you can use it for, and I am thinking if I should make the Red and Violet slightly bigger at both ends for vertical mode - although it flips the colors upside down as that is an issue from Vertical to Horizontal at the moment in aM. But overall, the ends might need some more in vertical to be shown more like the rest.
Here is the Horizontal mode although not really the purpose of this Gradients:

And here another in Vertical mode, but here it sadly flips the colors in opposite direction - here I might need to adjust things a little at the ends to make the 2 end colors show more up, but I will think about that.

Enjoy, if anyone is going to use it. I was thinking of doing some fluting and seeing how it does with that and the notes :)

-- Darkijah