How E.S.P. works is you just get a onetime code with the synth, and it can only be redeemed once ever.

Nuked used a non commercial license specifically to get Roland to look the other way, and it seems to have worked. But a non commercial license will probably limit the usefulness of this, because it's clearly intended to be used in music production, which is commercial use.

And legally, this is indeed more problematic than the use case for nuked-sc55 (playback old midis).

But they haven't stopped mame from trying to emulate their hardware yet. which gives hope that the bring your own rom will cause no trouble.

If Yamaha is informed of this before public distribution, the hope is that they adapt it to the state that it will playback all the midis properly, and then sell it at a fair price. I do think as long as this is not publically distributed before Yamaha sees it, an arrangement might get worked out. if attention is gotten by means of public dsitribution, that is likely to go much more wrong if they care.

zaphod77 wrote on 2026-06-03, 14:17:

In particular, the reverb, chorus, filter, and envelope stuff *must* be correct, because these parameters modify the original sa […]
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In particular, the reverb, chorus, filter, and envelope stuff *must* be correct, because these parameters modify the original samples to create the default patches.

Can we do better inside a daw? sure. but to playback existing midi data, the already existing stuff needs to be implemented correctly. and that's what i want. I'd like to see this project playback the entire XG ff7 soundtrack correctly.

I would like to see this project to end up being dual licensed, with yamaha being given a separate license that lets them (and them only) do whatever they want with it (like sell us an s-yxg2000), while the free download will not come with roms, and have a basic license that requires that you own the synth that you dumped the ROMs for. Yamaha's ESP only comes as a free license with the actual hardware, so this new project should work the same. if you own real hardware, you can use it, while if you don't you can't. I think that as long as it works that way, Yamaha won't have an issue. I am curious if enough can be dumped from the actual synth using sysex instead of a rom dump, though i'd guess you can't extract the samples this way.

Then Yamaha could maybe make a new s-yxg50, s-yxg80, s-yxg100, s-yxg125, and s-yxg2000. with the prices going up as the numbers do. S-yxg2000 i could see having a similar price to Sound Canvas VA, with s-yxg50 being anywhere from 20$ or so to free. Most people who just want to play midi files would use the remade s-yxg50, while serious xg music makers would want the 2000.

It's a common misconception that XG FX are used as part of a programs 'sound' internally. There's no MEG element involved. All programs are dry and processed with AEG and FEG1 to 4 only depending on element count, no FX DSP is used by XG internally, it's purely user FX as send and variation.

I've reverse engineered all the FX DSP from syxg50, so Chorus and Reverb FX are faithful, just sound better due to not limited by hardware constraints of the 90s

The things is, this project is for music production, so the focus is on the sound, not the FX, but 90s dsp is well documented, it won't be difficult to emulate. Although Yamaha were quite clever in using the same DSP for many uses, it's not like there's Reverb DSP, Chorus DSP, Flanger DSP or Delay DSP etc, it's all basically the same thing sharing common DSP.

Bu, all sysex and midi is built in and all FX do route to real FX DSP that does something so it will play a midi file or stream and respond similarly. I've used all existing parameters so the FX are constrained to the limits of the hardware. It all matches in that regard.

All the licencing stuff is only going to be known after I send them the final synth. It is already sounding so much better than the hardware and takes many aspects of it beyond what was possible in hardware, so we will see. If not, I'll have quite a nice synth nobody on the planet has to make music with which has value in itself.

that's odd, because other people i've chatted with do state that the filter, and the envelope generators have default settings.

And these default settings are applied to the parts. the adjustments done by the mid controllers are relative to these defaults set for the part!

THE reverb and chorus are separate. you are correct there. but the following parameters are relative.

nn 15 1 00 - 7F VIBRATO RATE -64 - +63 40
nn 16 1 00 - 7F VIBRATO DEPTH -64 - +63 40 (drum part ignores)
nn 17 1 00 - 7F VIBRATO DELAY -64 - +63 40 (drum part ignores)
nn 18 1 00 - 7F FILTER CUTOFF FREQUENCY -64 - +63 40
nn 19 1 00 - 7F FILTER RESONANCE -64 - +63 40
nn 1A 1 00 - 7F EG ATTACK TIME -64 - +63 40
nn 1B 1 00 - 7F EG DECAY TIME -64 - +63 40
nn 1C 1 00 - 7F EG RELEASE TIME -64 - +63

these are all relative. they are changes from what is in the patch.

say you grab that silly xg by dls file. it has the samples. but they are recored with the filter and envelopes alreacy applied. so if you try to playback midi with them that actually messed with them, things sound completely wrong.