Hi everyone!
I've gotten interested in the so-called SA-synthesis by Roland, since it seemed like there was no info on how it actually worked internally. I've got the custom chips decapped and I analyzed their microscoped pictures, reconstructing a perfect logic level copy.



I've encoded the result of my analysis on a new VSTi/AU plugin, which can be used to play sounds from all SA-based Roland product, like the MKS-20, the RD-200, the P-330 and the Rhodes MK-80.

The analog parts, like the chorus and phaser, are still to be done, but they can easily be replaced with existing effect plugins.

You can find more here: https://github.com/giulioz/rdpiano
And I've played a demo here: https://www.youtube.com/watch?v=7w0uvZ-OZ7U

As I have a Rhodes MK-80 (for 30 years now ..), let me say - this plugin sound totally the same
This strange synthetic, but very playable sound ...

And it's beyond fascinating to me, I totally adore the guys emulating the motorola/freescale DSP, but this is a recreation of a Roland custom chip ... wow

May I ask you, how long did this project take? Aside from your skills, which are obviously there

Great work. Thank you for your efforts.

Thank you so much!
I started working on this in September, and finished it just now. I had to teach myself how to reverse engineer silicon, as I never did before. I also did a talk about it: https://media.ccc.de/v/38c3-propriet...h-a-microscope

Giulio, thanks so much for this - super interesting, educational and fun!

and the bottom line ... 'it's a sample player!'

cheers!

Very cool.. Impressive you got it all working so nicely.

I like the sound - seems to be going into the right direction! I'm having one problem (Mac OS Sequoia, M2 pro, Logic): there is a constant clicking. Could it be there's a problem with 96kHz host setting? (Same thing on intel Macbook: 48kHz OK, 96 kHz clicking periodically)

Hi giulioz

This i brilliant! You´re brilliant!

Cheers Pelle

Amazing work giulioz,

Is there a reason you haven't bought out plugn versions of your other project:

MiniJV880 and Nuked SC-55?

Also any chance of the newer synths such as the JD-990?

I watched the Youtube demo. Huge question is, would it not be better to buy one of the sampled libraries.

Interesting effort though. But to me, from memory, it sounded like something was missing.

Well done for the effort.

Loved it, and I have RD-2000. Always good have a good plugin which I can carry around. I love Piano 1+ Piano 3+ EP1 Stack on this, try it out sometime.

Ciao Giulio.
Enjoyed the talk a lot.
You're quite a talented chap.

Tittle is a tad misleading though, since building an affordable (aka no Kurzweil K250) sample based piano was not trivial in the mid '80s. And the Korg M1 wasn't there yet.

The MKS-20 page at Wikipedia had already some infos from Spectrasonics, but it's been updated as per your findings for MAME, which is great.

https://en.wikipedia.org/wiki/Roland_MKS-20

That's much more than basic sample playback, and offers a lot of digitally controlled expressive means, close to the K250, LA-synth and additive synthesis as you mentioned.
Also, the "voice preserve" aka "patch remain" ability on sustained notes is something that not all current digital synths can do either.

Dave Rossum sure will appreciate those findings and tricks. He always said Roland engineers were very good and creative when facing technical or economic limitations, much like him.

https://www.youtube.com/watch?v=XAuEv29gHo8

Heck, they even had a digitally controlled analog synth that could - almost - do FM like sounds back then (JX-8P) . No wonder hybrid synths are back in the game today.

Most likely the analog parts of the signal path (chorus, tremolo and EQ) which are not emulated int the digital domain.

Hi Poumtschak, thank you so much for your kind words!

I have to say that I choose the title to be more "attractive". It's unfortunately difficult to get into those kind of conferences and sometimes you have to stay a bit more on the "flashy" side. Anyway, I didn't mean to downplay their achievements in any way, more like to criticize their lack of openness when it came to explain how it worked. If you look at other companies at that time (such as Ensoniq) they were much more transparent.

The very impressive thing they achieved is honestly the amount of voices (160 samples at the same time!), but apart from that playing samples from a ROM was already quite common for the time, especially if you look at drum machines. Also, if you look at how the Korg DWGS series worked (https://acreil.wordpress.com/2017/10...hesizers-1984/) it's extremely similar, using the same technology with fujitsu gate arrays even 2 years before.

I added the chorus and tremolo now to the plugin, doing the analog part accurately is very hard but it's a start!

I get your point about the clickbait... er, "marketing oriented" tittle.

Like most R&D heavy businesses, Roland has always been focused on protecting their IP. Which figures.

Thanks for the link to the acreil blog and music.

Looking forward an accurate JD-990 and JV-1080/2080 emulation now, so I can get rid of the hardware gear before it goes belly up, while still being able to playback my old MIDI sequences.

Keep up the good work and musicianship.

I read about this on KVRAudio.com yesterday, and wanted to try it, but I must have missed something. I downloaded the .VST3 file from https://github.com/giulioz/rdpiano/r...iano_juce.vst3, but my DAW (Cakewalk) doesn't even see it during a scan of VST2/3 plug-ins on my Win7 system.

Are there any other files I need for it? I haven't tried the standalone version yet, but I'll try that tonight.

Even if this never works on my system, I wanted to let you know I think it's very interesting how you were able to reverse-engineer this, based upon the processor logic. And I wasn't that familiar with Roland's "SA" synthesis at first, but your video definitely made me want to seek out these sounds.

Steve

Bravo !

I tried this on mac, the standalone and Daw plugin. But it has a bug where it will sustain the odd note forever unless I change pianos back and forth to stop it. So not useable for me.

Does anyone know the best place to post questions to the developer (@giulioz)? I've posted a question here (as have others), but I'm not sure they're being seen. (He may get dozens of messages each week from Gearspace and other forums, so he may not read each one.) I'm just trying to get this to work in Windows 7, but my DAW doesn't even scan the .VST3, let alone try to load it into a project.

Thanks.

Steve