Filters
Analog
- Guitar tone control
- impedance matching http://www.learnabout-electronics.org/ac_theory/transformers04.php
- resistors, capacitor RC circuits http://www.electronics-tutorials.ws/filter/filter_2.html
- capacitor calculation: http://www.convertunits.com/from/farad/to/picofarad
- identifying capactiors: http://grathio.com/assets/capacitor_tags.pdf
- Wolfram Alpha: http://www.wolframalpha.com/input/?i=1+%2F+%28.0000000047+*+10000+*+2+*+3.1415%29
Digital
- Max filter tutorial: https://cycling74.com/wiki/index.php?title=MSP_Filter_Tutorial_1:_Simple_Filters
- cutoff frequency, stopband, passband, bandwidth, q, resonance, poles, slope, phase shift, delay, order,
- impulse, impulse response, fir, iir
- Links to all Max filter tutorials: https://cycling74.com/wiki/index.php?title=Special%3ASearch&profile=default&search=filter+tutorial&fulltext=Search
- Filter modulation and envelopes
- the frequency domain: noise gates, parametric eq
- forbidden planet (max example)
- fft filter by Katja Vetter https://reactivemusic.net/?p=11207
- sinusoidal, harmonic, stochastic models
Other
We usually think of filters in terms of frequency. Any process that removes information is a filter. Curation or abstraction, for example.
- multirate DSP: upsampling, downsampling, decimation and interpolation https://reactivemusic.net/?p=11392
- slew-limiter: https://reactivemusic.net/?p=2506
- randomness, entropy
- heterodyne filter: https://reactivemusic.net/?p=17338
- nothing-detector: https://reactivemusic.net/?p=11770
Reversability
- encryption – Markus Brandau – http://upcommons.upc.edu/pfc/bitstream/2099.1/4858/1/MarkusBrandau.pdf
- various methods: https://reactivemusic.net/?p=7752
- Fiber optic noise cancellation: https://reactivemusic.net/?p=6680
- Noise cancellation for light: https://reactivemusic.net/?p=6381
- language translation http://richard-blanco.com/book/city-of-a-hundred-fires/mother-picking-produce/
examples
- Simple phase cancellation (disappearing-act.maxpat) https://reactivemusic.net/?p=8879
- Encryption by masking and phase cancellation: (phase-cancellation-example.maxpat)
- 2 methods of reversible audio encryption in Max: reciprocal and frequency shifting: https://reactivemusic.net/?p=9030 (voice-encryption2b.maxpat)
- FM, AM, and SSB modulation/demodulation in Max https://reactivemusic.net/?p=8885
- weird spectral symmetry: https://reactivemusic.net/?p=11747