mvclpf3 — Moog voltage-controlled lowpass filter emulation.
Mvclpf3 is an digital implementation of the 4th-order (24 dB/oct) Moog ladder filter originally written by Fons Andriaensen. According to the author, mvclpf3 "is based on mvclpf2 , with two differences. It uses the the technique described by Stilson and Smith to extend the constant-Q range, and the internal sample frequency is doubled, giving a better approximation to the non-linear behaviour at high freqencies. This version has high Q over the entire frequency range and will oscillate up to above 10 kHz, while the two others show a decreasing Q at high frequencies. Mvclpf3 is reasonably well tuned, and can be 'played' as a VCO up to at least 5 kHz".
istor --initial disposition of internal data space. Since filtering incorporates a feedback loop of previous output, the initial status of the storage space used is significant. A zero value will clear the space; a non-zero value will allow previous information to remain. The default value is 0.
ain -- input signal.
xcf -- filter cutoff frequency. The useful range is around six octaves below and above middle C (pch 8.00).
xres -- resonance, limited to the interval [0,1].
Here is an example of the mvclpf3 opcode. Play mvclpf3.csd
Example 647. Example of the mvclpf3 opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.