Re: Dead Synth (Was:Mains voltage step-down converters)

Posted on 2024-03-19, 22:52

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

do NOT get me started on Brexit, for the love of god. and that's not all, on top of it - Parcelforce are not accepting Bank cards not issued by UK bank for online payment of duties: https://www.reddit.com/r/royalmail/comments/qfhosv/parcelforce_keeps_denying_my_card_when_i_try_to/ it's really …

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Re: Dead Synth (Was:Mains voltage step-down converters)

Posted on 2024-03-19, 22:42

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

Tiido wrote on 2024-03-19, 22:38: but shipping cost would need to get covered... IMHO, the "Customs Clearance" will be the biggest problem.

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Re: Dead Synth (Was:Mains voltage step-down converters)

Posted on 2024-03-19, 22:36

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

use the same or similar PSU hmm, too many reports from actual owners it works just fine on 220-240V and the switch-mode power supply inside is in fact universal: https://www.vogons.org/viewtopic.php?p=998135#p998135 https://www.vogons.org/viewtopic.php?p=995084#p995084 and so on. So, I am staring …

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Re: Dead Synth (Was:Mains voltage step-down converters)

Posted on 2024-03-19, 22:18

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

so, am I right and there is no SC-S70 Service Manual available, at least not one that is in the public domain?

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Re: About Roland Virtual Sound Canvas 3

Posted on 2024-03-19, 22:05

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

binarymaster wrote on 2024-03-19, 21:58: recently I was able to create a tool for decrypting Crystal's CWCDLS8.CLS sound banks nice, I like any decryption tool and it's good to see more sounds liberated.

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Re: sc55mkII vs. sc55st ROM Analysis and Demo Song?!

Posted on 2024-03-18, 02:31

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

I am fond of the Nuked-x projects, silicon based reverse engineering has the protential for completely accurate behaviour although I believe we all are - it's simply incredible and fascinating work by @nukeykt ! I hope he gets his hands on few more SC-55 units, because the MCU firmware dump only he …

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Re: sc55mkII vs. sc55st ROM Analysis and Demo Song?!

Posted on 2024-03-18, 02:07

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

is doing "RIAA IIR filtering" (and doing it twice one after another), because that is what the community somehow took for a fact and what projects like 'emusc' are utilizing.... ...when at least I have 0 evidence such thing is correct... I want to update this thread, because after I don't know for …

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Re: Nuked-SC55, low-level Roland SC-55mkII emulator announcement

Posted on 2024-03-17, 23:29

by

by mattw

in Release Announcements

in Release Announcements

I don't have complete ROM dumps for original sc-55 to support it first of all, you made incredible progress in no time - real impressive! So, I have original SC-55 with v2.00 ROMs, MAME dumps are from v1.21 unit, but I guess you say they are incomplete, because of the magic you did: https://twitter …

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Re: Help IBM PS/2 model 8556 wiring 1.44MB floppy

Posted on 2024-02-13, 19:13

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

cbcduna wrote on 2024-02-13, 18:45: With your way of wiring the unit also works, but it detects it as a 2.88 Mb unit and not as a 1.44 Mb unit. thanks, in any way, it's good we got to the bottom of it.

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Re: Roalnd software emulation? GitHub project in post.

Posted on 2024-02-08, 22:58

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

Some news https://twitter.com/nukeykt/status/1752965047179981212?t=Gf5BjSOblQ85WGIEKbPBaw&s=19 I presume the dump is not publicly available, right? So how much of the SC55s hardware is still an unknown quantity? Is this the last chip they had to figure out? it's the last ROM that was not dumped. …

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Re: Help IBM PS/2 model 8556 wiring 1.44MB floppy

Posted on 2024-01-20, 09:24

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The result for Floppy 3,5 1.44Mb the correct status is Pin2=0, PIN4=0, PIN9=0, PIN17=1, PIN27=0 and PIN33=0. With this disposition the function is correctly and the driva load reference Disk and SO fine. I am glad to hear, you found a solution that works (in you case), but are you saying with my …

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Re: Help IBM PS/2 model 8556 wiring 1.44MB floppy

Posted on 2024-01-07, 17:44

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

@cbcduna: do I understand right - you can boot the "Reference Diskette", but you cannot boot DOS from the floppy? so, maybe, everything is alright, I mean I doubt that I ever tried to boot DOS from the floppy. And after all the whole point is to be able to boot the "Reference Diskette", then after I …

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Re: Help IBM PS/2 model 8556 wiring 1.44MB floppy

Posted on 2024-01-06, 22:22

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Any idea? unfortunately, I don't have any idea - it worked very well for me. also, as I mentioned here: https://www.vogons.org/viewtopic.php?p=1198293#p1198293 you need to use the floppy only once - to make "IML"-partition, then make image of that SCSI HDD using regular PC and SCSI card (f0r backup …

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Re: The Soundblaster DSP project

Posted on 2024-01-04, 15:20

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

fixing the hanging note bug makes a huge difference. yeah and you can use cool setup like this one: https://www.vogons.org/viewtopic.php?p=521170#p521170 i.e. not only avoid the DMA bug, but going pure digital without any crappy noisy DACs. So, you can use CMI8330-based card (like AV310), because …

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Re: Show us your custom Physical mt32-pi Builds

Posted on 2024-01-03, 21:26

by

by mattw

in MT-32 General

in MT-32 General

Honestly, I don't understand what is the point of MT-32Pi and I will be very glad if someone can explain it to me - what are the advantages (if any)? Especially, when from my point of view using Thin-Client beats it in every possible way, including it's several times cheaper plus it allows to use …

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Re: Faulty Roland SCC-1 (no audio): attempts to diagnose and repair this card

Posted on 2023-12-30, 07:08

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

Holtek HT27C020-70 EPROM chips those are One-Time-Programmable, but still you're in luck that you found any, because SOP32 '27C020' PROMs seem to be very rare now to find and it's better than having nothing. So, I see your board is with chip marked with"A2", i.e. it's V2 ProgramROM. that's why I …

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Re: Faulty Roland SCC-1 (no audio): attempts to diagnose and repair this card

Posted on 2023-12-29, 11:15

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

Tempus wrote on 2023-12-29, 10:26: and the instruments from that ROM made clicks and noise. thank you, that is good to know and it makes perfect sense. so, @Shponglefan can rule out all 3 WaveROM chips - they all cannot be faulty and focus on the rest...

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Re: Yamaha MU2000 Service Manual - where to get it?

Posted on 2023-12-29, 09:48

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by mattw

in Marvin \ Sound

in Marvin \ Sound

Undoubtedly, though it's not one that I possess. You might try requesting it from Yamaha's service department; that's how I obtained the MU2000 service manual. (Granted, that was more than fifteen years ago...) thanks again, I am asking all of those, because I am trying, as much as I can, to help …

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Re: Faulty Roland SCC-1 (no audio): attempts to diagnose and repair this card

Posted on 2023-12-29, 09:19

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

Then maybe moving to the main program ROM next. yeah, I also think if any of the 3 WaveROMs has a problem it will cause corrupted sound rather than no sound - but who knows, maybe the ProgramROM has CRC check for the WaveROMs and if some of the WaveROMs is bad/corrupted/missing it just stops …

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Re: Faulty Roland SCC-1 (no audio): attempts to diagnose and repair this card

Posted on 2023-12-29, 03:01

by

by mattw

in Marvin \ Sound

in Marvin \ Sound

Maybe it can serve as an MPU-401? I mean if you can't figure it out. Yup, it does work perfectly as an MPU-401 interface. So if all else fails it's still useful for that. regarding the Intelligent MPU-401 chip, maybe this post I made will be of interest to you: https://github.com/schlae/mpu-imc/ …

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