Copyright (c) 2025 by E. Lamprecht. All rights reserved. See LICENSE.md for licensing terms and TODO.md for notes on the current development status.
mz2 [option]... <input_file>
MZ2SYNTH is a wavetable synthesizer inspired by the ANS synthesizer built by Yevgeny Murzin in various versions up to 1958, and currently housed in the Glinka State Central Museum of Musical Culture in Moscow (https://en.wikipedia.org/wiki/ANS_synthesizer).
MZ2SYNTH models 720 oscillators spanning 10 octaves, with oscillator no. 294 set up with a fundamental frequency of 440 Hz and all others calibrated to this using equal temperament. Each oscillator has four channels, these generating sine, square, sawtooth and triangle waves. The wave-table is initialized in such a manner that, at the desired audio sampling frequency, no aliasing will occur. In practice, this also means that oscillators with fundamental frequencies above the Nyquist frequency corresponding to the desired audio sampling frequency would be silent.
Input takes the form of a PPM graphics file with 720 rows and as many columns as desired. MZ2SYNTH begins at the leftmost column and advances, column by column at the desired rate. By default, the amplitude of the sine, square, sawtooth and triangle wave channels is multiplied by the red, green, blue and luminance channel values at each instant within the run, but the specific channels can be linked as desired. A simple bumpless transfer mechanism is implemented so that oscillator channels are rapidly but smoothly turned on or off.
Each of the sine, square, sawtooth or triangle waves can be linked to the (r)ed, (g)reen, (b)lue, (l)uminance values of the graphic file pixels, or else (m)uted. See option -c below for syntax.
Output takes the form of a stereo 32-bit floating point PCM Sun audio file.
The following options are available (case insensitive):
| Short form | Long form | Description |
|---|---|---|
| -h | -help | Show help screen and exit |
| -v | -verbose | Toggle verbose textual output mode |
| -d | -debug | Toggle debugging output mode |
| -p | -dynamic-compression | Toggle dynamic compression on |
| -w | -overwrite | Toggle audio file overwrite mode |
| -x | -fixed-phase | Toggle on fixed-phase mode (slower, accurate) |
| -z | -zero-phase | Toggle on zero-phase mode (changes beat freq.s) |
| -a cps | -advance cps | Set advance rate in columns per second |
| -c XXXX | -channel selct XXXX | X in (R,G,B,L,M) |
| -m mul | -volume-multiplier mul | Multiply raw volume by factor mul > 0 |
| -o ofn | -output-file ofn | Set output file name to ofn |
| -r ftr | -transition ftr | Set transition TC (as fraction of |
| -s spr | -sampling-rate spr | Set sampling-rate in c.p.s |
- Input file: input.ppm
- Output file: output.au
- Channels: sine:square:sawtooth:triangle = R:G:B:L
- Volume multiplier: 0.1
- Transition fraction: 0.01
- Sampling rate: 44100 c.p.s.
- Fixed phase: off
- Zero phase: off (i.e., phases are randomized at start by default)
-
Generate file track01.au from input track01.ppm, advancing at 12 columns per second, at a sampling rate of 48000 c.p.s. Enable dynamic compression, overwriting of output if it exists and verbose textual output.
mz2 -verbose -overwrite -advance 12 -output-file track01.au -dynamic-compression -sampling-rate 48000 track01.ppm -
As above, but play real-time through the SOX play program with some effects, via a named pipe called fifo
- In one terminal enter:
mkfifo fifoplay --buffer 16384 fifo reverb deemph- In a separate terminal enter:
mz2 -verbose -overwrite -advance 12 -output-file fifo -dynamic-compression -sampling-rate 48000 track01.ppmThe play process will block until mz2 starts generating output.
WARNING: This synthesizer can generate very loud and very high-pitched sounds. Playing unknown inputs through powerful speakers or earphones can result in pain or hearing loss, so set your volumes low to start with, and beware of using volume multipliers larger than 0.01 or so until you become familiar with the audio that your input files generate.
NOTE: Intel Fortran (ifx (IFX) 2025.0.4 20241205) executables cannot write to named pipes as noted above, for reasons currently not known. There is a work-around:
- In a terminal, start mz2 as explained in the second step above, but writing to an ordinary disk file instead of a FIFO
mz2 -verbose -overwrite -advance 12 -output-file output.au -dynamic-compression -sampling-rate 48000 track01.ppm- After file generation commences, enter the following command in a separate terminal to play the file in real-time:
cat output.au | play - reverb deemph