Experimental Pitch-Shifter using Single Sideband Modulation
Archive · 20064 old posts
From the original SynthMaker forum (2004–2014), with its members’ names and dates.
rl ·
Inspired by a post by doug4350 I buried myself in my mad scientists lab and came out with an experimental schematic demoing single sideband modulation. SSB-M is simillar to ring modulation (RM), but in difference the modulated signal contains only one half of the sidebands.
The implementation uses an hilbert transform implemented with IIR filters (allpass with 90 degrees phase shift)
Here is a good lecture on the topic: http://www.mathworks.com/products/signa ... mdemo.html
The schmatic lets you choose between RM and SSB-M, furthermore you can either modulate 2 oscillators or modulate an oscillator with a wavefile-loop to demonstrate pitch-shifting. For good results use a sinewave for osc 2 and start with low freq.
Parental Advisory: Explicit noize. Wicked sound mangling tool! 😉 (...and anti-aliasing is for sissies...)
(oh, and here is the link)
Tom7777 ·
Thanks for the example rl 🙂
doug4350 ·
WooHoo! 😮 🙂
I thought there might be something there... ATM, I'm too saturated and bogged down in my day job. Glad to be a mental spark plug rl 🙂 .
As it's approaching midnight here, the lecture will probably knock me out faster than ether at a fund-raiser 😀 .
I can also tell I'm due for some remedial math(s) if I'm gonna keep up with you guys & gals.
...and anti-aliasing is for sissies...
And so is transposing 😉 .
Aloha,
Doug
Tom7777 ·
I just found a bug (i think), not sure if its to do with the schematic or SM, to get the bug enable DS out then on the Freq control which is connected to the sine Osc lower this to its min value then move the knob control (whole module) and the audio will cut out. This won't happen if the values higher than its lowest value though.
Wrote something here? To have a post removed or your name hidden, write to [email protected].
SynthMaker