zynaddsubfx VS yamaha_dx7_rom_disassembly

https://github.com/hselasky/midipp supports 192 TET and there are some filters, see help section, that automagically microtone the input . Then you just round to the nearest TET. The difference is not noticable. Can playback this using SYSEX on ZynAddSubFX (3.0.6) https://github.com/zynaddsubfx/zynaddsubfx

DAW: https://github.com/zynaddsubfx/zynaddsubfx

I suggest that you look into open source audio synthetizers (like https://github.com/zynaddsubfx/zynaddsubfx) to see the approach they use.

I wrote the article mentioned by Ken: https://ajxs.me/blog/Yamaha_DX7_Technical_Analysis.html

I've unwittingly become a bit of a Yamaha FM Synth historian!

Here are some other contributions to reverse-engineering the DX7:

A fully documented disassembly of the DX7 ROM: https://github.com/ajxs/yamaha_dx7_rom_disassembly

A new firmware ROM that makes the DX9 function like a DX7:

I browsed through the repository as discovered by colejohnson66 downthread https://github.com/ajxs/yamaha_dx7_rom_disassembly. This is an example of superb, meticulous, lovingly documented work. The kind of thing you don't see every day, congratulations. The attention to detail is really just chef's kiss, starting with a really good repository name (a small thing, but still), continuing through clear and apparently comprehensive documentation of what you did and why, then on to beautifully formatted and commented assembly language (much better than the original source code I'd wager) with coherent and consistent paragraph commenting a particular delight, and finally (and very importantly) dedication to making sure others can reproduce your results and generate a matching binary too. There are likely to be other things of beauty in there I have forgotten to highlight, it's just that good. Oh the FAQ of course, what a great FAQ. Really I am being very wordy for someone that's lost for words.

BTW, I love retro computing too, this is my best attempt so far in the field https://github.com/billforsternz/retro-sargon. I aspire to similar standards to your good self, but I'm not there yet.

Very cool! This is really great work! It's awesome that there's been so many synthesiser related topics on Hacker News lately. I did a similar project myself to disassemble, and fully annotate the firmware for the Yamaha DX7: https://github.com/ajxs/yamaha_dx7_rom_disassembly

The biggest hint I could give anyone looking to disassemble a synthesiser operating system is to direct your attention towards the code processing individual MIDI messages. The code is invariably is huge mess, however you'll be able to very quickly identify the operating system's core functions, since the corresponding SysEx parameter numbers clearly identify what functionality you're looking at.

Anthony just released his annotated DX-7 ROM listing:

https://github.com/ajxs/yamaha_dx7_rom_disassembly