Välimäki and Houvilainen have published a number of articles about something called 'differentiated parabolic waveforms'. Basically, you square a digital sawtooth and put it through a one-zero differentiating filter (y(n) = x(n) - x(n-1)). What you get out is a slightly rounder (less aliasing) sawtooth. I've never actually tried this, but it looks pretty interesting and could easily be patched. Super simple.
The CMJ paper explains it in full detail. You might need a University-style subscription to get the actual PDF: http://www.mitpressjournals.org/doi/pdf/10.1162/comj.2006.30.2.19 but the reference is: Välimäki, Vesa, and Antti Huovilainen. "Oscillator and filter algorithms for virtual analog synthesis." /Computer Music Journal/ 30.2 (2006): 19-31.
On 11/23/2015 6:07 PM, Christof Ressi wrote:
I can think of at least two:
- wavetables filled with sinesum/cosinesum (possibly blending between different wavetables according to frequency --> many partials for low pitches, few partials for high pitches)
- transition tables (check out 3.audio.examples/J09.bandlimited)
Gesendet: Dienstag, 24. November 2015 um 02:30 Uhr Von: "Alexandre Torres Porres" porres@gmail.com An: "pd-list@lists.iem.at" pd-list@lists.iem.at Betreff: [PD] band limited (anti-alias) techniques
hi, I know about the oversampling + filtering technique, which you can patch it, but what are other techniques for creating band limited signals you people know (not only those you could do it as a pd patch)? Yes, I'm thinking about oscillators mostly.
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