http://matrixsynth.blogspot.com/2009/06/ae…synth-with.html
this video presents some interesting sample manipulation ideas. most of it is already do-able in the renoise sample editor and instrument editor. there is a cool feature that adds harmonics to custom drawn waveforms. if they could do it in the 80s, why not now??
YAY, NOSTALGIA!! I never made music with that, but I had it, and a few PD disks with tunes… and I actually have a bunch of tunes made by it on my mp3 player. turns mp3 player on and rocks out haha
Because that was Amiga, and now we have Windows, Mac and Linux. Because many steps forward in a crooked line will lead you in circles, or even spirals.
Either that or I didn’t have coffee yet, you decide.
What would be cool is the abbility to create waveforms by stacking harmonics ( additive synthesis ) in the sample editor
+1 for being able to add harmonics. Shouldn’t be to hard to implement, right?
Well, in theory, you could for example take two sine waves (sineA;sineB) and transpose sine B a few octaves up and lower its volume to your appropriate needs, render selection, snip to single cycle, and you should have your sine with 1 harmonic.
Absynth has a nice harmonic editor… edit: i don’t think Absynth includes subharmonics in their edit feature, Reaktor5 Subharmonic comes to mind…
Yes ofcourse …and there are a lot of vst out there that do a good job in additive synthesis ( zebra , spectra,etc …)
It is indeed possible to stack multiple sines with a different frequency on different tracks ( for controlling amplitude of each sine independently ) automating the volume sliders for each channel ( partial ) etc…
and render the whole lot to a new sample …
Downside is when creating something with 15+ harmonics …you use up 15 tracks …which is a bit overkill for creating a basic waveform …don’t you think ?
So easy …harmonics generator in sample editor would be a nice feature …hell I don’t even care if turns out to be native renoise waveform generator( as long we have control over the harmonics ) . 
http://www.easy-upload.nl/index.php/file/194a25257297964
I have a lot of fun with programming VST effects, and one of them does something similar.
This is a multiband filter which boosts/passes the exact frequencies of the keys you touch
on your MIDI keyboard in real-time… or you can select any track of your song to control it.
It’s quite strange to play “on” a drum track, or to play real-time on the noise you make by blowing into the microphone 
Soft Distortion is add harmonics to any waveform (u can use hard distortion, personaly i like analogue distortions)
In synth use Square os Saw wave and LP fileter high Resonance and use Cutoff to add harmonics to basic wave
i can recreate this with that High Resonanced Lowpass filter this is Self Resonance Waveform
Square 2 use only lopass filter to remove harmonics finally you get a clean Sine Wave
Ring mod is another way to get harmonic sound from 2 input waveform A+B out 1 and A-B out 2 and 1-2 mixed to one output but there are the input waveforms too
btw you can use comlex patters for that A-3 (220hz) 100%vol *3 *5 *7 *9 in other track and expinential vol down
theese are basic synth ways,
but if you use complex waveforms like Piano (wav) that is include lots of harmonics and timbre etc etc.
Square has A *3 *5 *7 *9 xxx harmonics,
Tri has A *2 *3 *4 *5 *6 *7 *8 *9 xxx harm
Sine wave didnt have harmonics,.
You need to know the basic note is need to high volume
i hope i can help you with this basic Sound Spectrum Harmonics
correct me if im wrong 
.,Fanta,.
www.sounddesign.co.hu