VOGONS


First post, by Jonas-fr

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Owner of a SC-55 here, I want to shrink down my setup (486 computer hooked to a SC-55 via MIDI) while retaining the SC-55 abilities. I'm currently focusing on getting a 1:1 copy of the SC-55 soundfont (I won't go in the debate between what's the closest soundfont today ,there's some very good clone/reproduction more or less faithful today but that's not the point of this topic). I'm wondering whether it would be possible to extract the exact sounds contained in one (or two) of the chips of a SC-55 to get a soundfont and then flash it on a Dreamblaster X2.

Of course if such dump was easy I think we already got one today they shouldn't be so many reproductions so I'm wondering whether the following will be possible (see it as an thought exercise) :

  • Dumping the actual digital bytes of the SC-55 soundfont from a real unit (in contrary of dumping the analog sound signal from each instrument as it is done today to make soundfont reproductions)
  • Extracting then converting the soundfont from Roland Sound Canvas VA to a format that could be flashed on a Dreamblaster (SF2 or DXB)

Regarding the first option we can try to do that via software (a glitch) to extract needed data, or by hardware by snooping signals with a logic analyser (non destructive method) or by boiling the needed chip(s) in acid a dumping by microscope the actual sound tables (tedious but it has been done on other hardware).
The first method (software) would needs an exploit which need some fairly good understanding of the underlaying firwmare of the SC-55. The second method (logic-analyser) seems to be the least hard one provided that we find a data line between soundbank memory and the CPU to be poked. The last method (acid then microscope analysis) would prove to be the hardest of the bunch and needing the more resources (time, talent, hardware).

Regarding the second option it would implies that Roland actually got the real soundfont for a SC-55 (and not a reproduction) actually flashed/burned in the factory while the SC-55 were made. If that's true then we "only" need to extract it from the software and then convert it to an usable format (SF2).

Well this is it, I certainly missed details here or oversimplified things by being naive but please bear with me and do not hesitate to chime in with your advices and/or view on the subject. And if feel up to join a reverse engineering effort on this matter (hardware of software) please chime in too 😀

Reply 1 of 37, by keropi

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have you seen the "Yucatan FX" daughteboard? it's the closest and effortless way to get sc-55ish midi output: New Waveblaster card : Reptile Paradise - Yucatan FX

🎵 🎧 PCMIDI MPU , OrpheusII , Action Rewind , Megacard and 🎶GoldLib soundcard website

Reply 2 of 37, by Jonas-fr

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Thanks for your input keropi. I wasn't aware of it so I wil keep an eye on it, but the topic isn't on the closest/more faithful solution but on getting actual SC-55 sound bytes on a waveboard (Dreamblaster on my case since it has flexibility to flash any soundfont that is under 64MB) 😀

Reply 3 of 37, by Oetker

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Isn't the issue just the sounds, but also the general behavior of the synth, such as the way it applies effects? As an SC-88 in 55 mode also doesn't sound right.

You could just find an SCB-55 😜

Reply 4 of 37, by darry

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You are talking about 2 things here.

a) Reverse engineering and replicating the SC-55 (likely in software).

b) Converting the sound banks of the SC-55 to something an X2 could use .

Option a) is likely possible but probably quite difficult. The ROMs are almost certainly unambiguously copyrighted (unlike the MT-32's which lie in more of a grey area), which would limit the practicality.

Option b) , even if possible (the way sounds are generated from samples on a Sound Canvas is more complex than what can be done with a soundfont or equivalent), would not sound the same because the synthesis engine is different . There is much more to an SC-55 (and its successors) than the sample ROMs in it .

EDIT: Other than for the academic exercise, I don't see why there would be an interest in reverse engineering the SC-55 ROMs just to produce a soundfont that won't sound like a real SC-55 anyway. This is especially true in the context of the Yucatan FX that Keropi mentioned .

Reply 5 of 37, by Jonas-fr

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Thanks for your feedbacks Oetker and darry !

@Oetker : So if the SC-55 applies effects on top of the sound this whole ordeal will fell through indeed.
I happen to have a NIB SCB-55 but I'll sell it because uno: as I'm downsizing (space issues) I feel awkward to use it and keep a hollow box with manuals in it and secundo: I may do some gigs with this setup and will be forever sorry if something happen to the SCD-55 (the same cannot be said with a nice but easily found Dreamblaster X2).

@darry : Regarding to legal issue it is easily bypassed if anyone who attempt to reproduce that dumps from one's own SC-55, at least were I'm currently located (France) it would be perfectly legal to do so (backup copy). I guess it would be the "sharing the ROM" part which would be illegal everywhere, I don't intend to do that.

Well I guess that if the SC-55 is more than just a rompler (rompler + FX) and that we cannot easily reproduce such FX in currently available waveblaster boards then the whole project isn't feasible.
The only other way would be to reverse the whole workflow from the SC-55 internal soundbank to the FX and implement all of it in a FPGA (maybe first on a widespread platform like MISTer and then on specialised FPGA sound cards) but this is again a magnitude bigger project altogether ! FPGA sound reproduction efforts are currently focused on OPL2/3, AY-xxx and SID but maybe one day it will shift to our trusty MIDI boxes, who knows ? : )

Reply 6 of 37, by cyclone3d

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You could also get an SCC-1 or SCC-1a

The SCB-55 would work as well.

Yamaha modified setupds and drivers
Yamaha XG repository
YMF7x4 Guide
Aopen AW744L II SB-LINK

Reply 7 of 37, by darry

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There's also the Roland Sound Canvas VA VSTi Plugin! Heads Up: Roland Sound Canvas VA VSTi Plugin! .

Both fully legal and quite authentic sounding, if comments are to be trusted .

Reply 8 of 37, by Jonas-fr

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@cyclone3d: I've got a SCB-55 but will sell it for reasons I stated just above your comment : )

@darry: I explained in my first post why Sound Canvas VA isn't on the table : )

Pushing further my search on this topic I stumbled upon this gem of a project (https://www.youtube.com/watch?v=0aCy3ccLZzo) and will monitor the hell of it. It's been a while I haven't kickstarted anything but this will get all my attention (a Kickstarter was going to be for 2020 Q1/Q2 but I don't see any evidence of that)!

Reply 9 of 37, by darry

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Jonas-fr wrote on 2020-07-09, 21:54:

@cyclone3d: I've got a SCB-55 but will sell it for reasons I stated just above your comment : )

@darry: I explained in my first post why Sound Canvas VA isn't on the table : )

Pushing further my search on this topic I stumbled upon this gem of a project (https://www.youtube.com/watch?v=0aCy3ccLZzo) and will monitor the hell of it. It's been a while I haven't kickstarted anything but this will get all my attention (a Kickstarter was going to be for 2020 Q1/Q2 but I don't see any evidence of that)!

@Jonas-fr : Sorry if I was unclear, but what I meant is why not simply buy and use the Sound Canvas VA on your modern computer (I assume you have one) and hook the up the 486 to it ? Sorry if I missed something obvious in your first post, which I just re-read, but I do not see why what I suggest would not be an option for you .

Reply 11 of 37, by Jonas-fr

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darry wrote on 2020-07-09, 23:58:
Jonas-fr wrote on 2020-07-09, 21:54:

@cyclone3d: I've got a SCB-55 but will sell it for reasons I stated just above your comment : )

@darry: I explained in my first post why Sound Canvas VA isn't on the table : )

Pushing further my search on this topic I stumbled upon this gem of a project (https://www.youtube.com/watch?v=0aCy3ccLZzo) and will monitor the hell of it. It's been a while I haven't kickstarted anything but this will get all my attention (a Kickstarter was going to be for 2020 Q1/Q2 but I don't see any evidence of that)!

@Jonas-fr : Sorry if I was unclear, but what I meant is why not simply buy and use the Sound Canvas VA on your modern computer (I assume you have one) and hook the up the 486 to it ? Sorry if I missed something obvious in your first post, which I just re-read, but I do not see why what I suggest would not be an option for you .

No problem maybe some of my meaning was lost in translation ! I want to shrunk down my setup so no more external device(s) and cables, that's why I want to retire my SC-55 and another computer with SoundCanvas VA would mean coming back to the same issues (another external device but this time with quirks !). Ideally I'd like an internal solution but I think I will wait until that FPGA Soundcard comes out and will do some homework on reversing the hardware of the SC-55.

Reply 12 of 37, by darry

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Jonas-fr, thanks for the clarification. I understand now (I had assumed you had a modern PC nearby, as many of us do).

I wish you luck on the reverse engineering thing, but I fear that there will be less interest behind something like this for the SC-55 than there was for the MT-32 as an official Roland alternative exists for the former, but not the latter .

I also hope that youtube project takes shape, as more options are always a good thing .

Reply 13 of 37, by carlostex

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In my opinion, best soundfont that comes close to SC-55 is a 4MB one for the Dream SAM 9407. It was so close, or probably a perfect copy that Roland couldn't just let them go without a lawsuit:

https://www.eetimes.com/atmel-and-crystal-sem … oland-corp-u-s/

I made the comparison and its virtually the same.

Last edited by carlostex on 2020-07-10, 23:49. Edited 1 time in total.

Reply 14 of 37, by Jonas-fr

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Very promising ! I never heard about those cards, I think they're unobtainium nowadays and basically rare than a SCD-55 ? I wonder if there's some attempt made to clone them since I read somewhere that dream branded chips can still be found.

Reply 15 of 37, by darry

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Jonas-fr wrote on 2020-07-10, 22:53:

Very promising ! I never heard about those cards, I think they're unobtainium nowadays and basically rare than a SCD-55 ? I wonder if there's some attempt made to clone them since I read somewhere that dream branded chips can still be found.

The Yucatan FX (resurrected Cancun FX) mentioned earlier in this thread uses a Dream chip and the infamous GS ROM that Roland sued over and then licensed .

I have a Monster MIDI which uses the same Dream chip and ROM, so sounds essentially the same as the Yucatan FX should . I do not find it that close to a Sound Canvas . I prefer my SC-88VL in SC-55 mode to it. I will probably be buying an X2 when they are back in stock and putting the Monster MIDI back in storage .

Here is a sample recording from my Monster MIDI . Forgive the clipping .
download/file.php?id=81343

It is the Water World track from Duke Nukem 3D

Reply 16 of 37, by carlostex

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darry wrote on 2020-07-10, 23:04:

The Yucatan FX (resurrected Cancun FX) mentioned earlier in this thread uses a Dream chip and the infamous GS ROM that Roland sued over and then licensed .

I have a Monster MIDI which uses the same Dream chip and ROM, so sounds essentially the same as the Yucatan FX should . I do not find it that close to a Sound Canvas . I prefer my SC-88VL in SC-55 mode to it. I will probably be buying an X2 when they are back in stock and putting the Monster MIDI back in storage .

AFAIK, the GS ROM Roland sued over isn't the exact same the one that came with the Cancun FX.
It follows the GS standard but doesn't sound close because it had to be changed significantly.

Any user with a card that has the SAM 9407 (EWS64, Guillemot) can try the 4MB soundfont, that sounds virtually the same as a Sound Canvas. I don't remember the file name exactly now but its no wonder Roland sued.

So they had to license and change significantly which resulted in the Cancun FX.

Reply 17 of 37, by darry

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carlostex wrote on 2020-07-10, 23:59:
AFAIK, the GS ROM Roland sued over isn't the exact same the one that came with the Cancun FX. It follows the GS standard but do […]
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darry wrote on 2020-07-10, 23:04:

The Yucatan FX (resurrected Cancun FX) mentioned earlier in this thread uses a Dream chip and the infamous GS ROM that Roland sued over and then licensed .

I have a Monster MIDI which uses the same Dream chip and ROM, so sounds essentially the same as the Yucatan FX should . I do not find it that close to a Sound Canvas . I prefer my SC-88VL in SC-55 mode to it. I will probably be buying an X2 when they are back in stock and putting the Monster MIDI back in storage .

AFAIK, the GS ROM Roland sued over isn't the exact same the one that came with the Cancun FX.
It follows the GS standard but doesn't sound close because it had to be changed significantly.

Any user with a card that has the SAM 9407 (EWS64, Guillemot) can try the 4MB soundfont, that sounds virtually the same as a Sound Canvas. I don't remember the file name exactly now but its no wonder Roland sued.

So they had to license and change significantly which resulted in the Cancun FX.

I think you may be at least partly mistaken . I can't speak for the Cancun FX, as I have never seen a photo with the sticker removed from the ROM. But even one of Dream's datasheets confirms the Roland source sample ROM was being offered as an option alongside the CleanWave ROM .

According to ftp://retronn.de/docs/pc_hardware/wavetables/dream/9703.pdf , the ROM part numbers are as follows .

Validation for following ROMs
•GMS960800 Roland 8Mb
•GMS970800 CleanWave8
•GMS963200 Roland 32Mb
•GMS973202 CleanWave32Mb

If you look at the ROM that will be used for the Yucatan FX : Re: New Waveblaster card : Reptile Paradise - Yucatan FX and Re: New Waveblaster card : Reptile Paradise - Yucatan FX you can see it is a GMS963200

If you look at the ROM from the Monster MIDI that I have : Re: Roland SCB-55 in 2020 - fair price and how to find one? you can see it is a GMS963200

According to http://www.os2museum.com/wp/of-g-men-and-farmers/ , the Roland sampled version continued to be offered as an option along with the CleanWave version, as mentioned before .

The SAM9407 compatible GS soundbank may or may not be the same as the one in the GMS963200 ROM . It would be nice to be sure .

Can you provide some references regarding this ?

Reply 18 of 37, by Jonas-fr

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I'm a bit puzzled by all these info. You mean that any SAM9407 based soundcard/daughterboard loaded with a particular soundfont (dumped from a Roland SC-55)? Can sound exactly like a SC-55 ? I'll be willing to test that since I have some guillemot cards, I just don't happen to have the sound font you're speaking of. But be happy to get my hands on it and do some comparison !

Reply 19 of 37, by darry

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Jonas-fr wrote on 2020-07-11, 10:02:

I'm a bit puzzled by all these info. You mean that any SAM9407 based soundcard/daughterboard loaded with a particular soundfont (dumped from a Roland SC-55)? Can sound exactly like a SC-55 ? I'll be willing to test that since I have some guillemot cards, I just don't happen to have the sound font you're speaking of. But be happy to get my hands on it and do some comparison !

I believe the soundbank is the one referenced here :
Re: TerraTec EWS 64 series sound cards?

EDIT: I believe you can get it here :

http://vogonsdrivers.com/getfile.php?fileid=144&menustate=0

EDIT2: As for it sounding exactly like the Sound Canvas, you'll have to be the judge of that . It would be really nice if somebody could record a representative MIDI files using
the Dream GS ROM bank, the GS 94b file and a real SC-55 . Maybe that's already been done and I have not found it yet .