[BlandDuck]

I know there is a bunch of new DX7 implementations on more modern hardware, i.e., the Raspberry Pi.

When implemented on modern hardware, wouldn't it be possible to run the algorithm at a higher CPU processing speed, to reduce the aliasing at the higher notes, and avoid the need for keyboard scaling and thus preserve the timbre of the higher pitched notes?

[cesaref]

You mean, would it be possible to oversample the algorithm, run it effectively at a much higher sample rate and reduce the audibility of the aliases? Yes, it'll definitely help, but no, it's not possible to eliminate this effect, even with monstrous levels of oversampling.

The problem is that, say, a piano keyboard runs from 30Hz to 4Khz, so to get an even tone, at the top of the keyboard, you are only hearing 4 harmonics of the fundamental, whilst at the bottom, you potentially have roughly 1,000 harmonics in the audible spectrum.

Without fiddling with the voice with keyboard scaling, that same tone with 1,000 harmonics played at the top of the keyboard will generate a 4Mhz frequency, so you'd need a 2Mhz sample rate to avoid the aliases reflecting into the audible spectrum.

So that's 45x oversampling, which is a scary amount of effort to throw at the problem, to resolve the issue for this one contrived sound.

Now if you modify the above sound, and double the modulating frequency (the operator pitch) then you'll double the oversampling required, and you have basically limitless control to create higher and higher levels of harmonics to tame, so you can always fiddle with the setting to produce aliasing if you try hard enough :)