Hi Orm,
Orm Finnendahl schrieb:
did anybody implement a frequency shifter using single-sideband modulation with Hilbert-Transform in pd?
If so, I'd be very much interested in it.
If I remember correctly, you're on Linux, right? Then maybe this LADSPA plugin (use with plugin~) by Steve Harris might do what you want, and it shouldn't be too hard to port to PD native:
[Quoting http://plugin.org.uk]
Bode frequency shifter (bodeShifter, 1431)
A Bode/Moog Frequency Shifter is a popular analogue synth module, it works by shifting all the frequencies of an input signal up or down by a specified frequency. This version shifts in both directions at the same time as its almost no extra work and its often useful to have both directions.It doesn't actually work in the same way as an analogue Bode/Moog, which use Dome filters as the core, it uses a Hilbert Transformer, which is much simpler to implemtent in digital systems. The output is very similar though, and people are familiar with the name Bode.The theory of operation is pretty simple, and uses some clever maths to cancel out the upper or lower sidebands of a ringmodulator applied to the input signal. Read the source if you want more information. The Hilbert Transformet coefficents came from mkfilter, the excellent filter calculator, available at http://www-users.cs.york.ac.uk/~fisher/mkfilter/.
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