VOGONS


Fixing the Roland CM-500 Vibrato Bug

Topic actions

Reply 20 of 35, by Spikey

User metadata
Rank Oldbie
Rank
Oldbie

So Cloud, while I think of it, were you calling the CM-500 a 3rd gen MT-32 device, given it has the sound quality improvements of the 2nd gen, plus some quirks? Or am I getting confused here?

Reply 21 of 35, by jaffa225man

User metadata
Rank Newbie
Rank
Newbie
Cloudschatze wrote on 2023-01-10, 03:33:

Separate from the LFO/vibrato issue, I am currently troubleshooting yet another errant CM-500 behavior, this time related to the MIDI switching/handling function of the Mitsubishi 7702 MCU. If anyone happens to have a CM-500 with a serial number greater than ZE13000 (with corresponding "CM-500 1.02" ROM @ IC22), can you please get in touch with me?

Not that it matters or will help, but my serial number, which is ZD83743, decodes as being unit # 3,743 from May of 1992 (1.00 IC22 ROM), so you really seem to want someone with a serial number after ZE13743. Of course, this is not a real concern as the release date must be from August of 1992 or later (and having the IC22 1.02 ROM), but I found it interesting that I have a unit number greater than your requested unit with an earlier release.

That silliness aside, I'm probably about to be disillusioned with another unit that won't help you, but we'll see when it arrives. It's got the serial number of ZE80482, which I decode as unit # 482 (lower probably due to the model number change from dm-500n to dm-500n-3) from March of 1993.

I probably should have consulted you before making this frivolous purchase, as it probably doesn't have that 1.02 IC22 ROM version, and you might already be aware of it. But, anyway, it will give me a chance to compare its, hopefully true, General MIDI support to mine's falsely labeled General MIDI support (which has the Sine Wave variation 8 at PC#81, yet not Breath Noise at variation 0 of PC#122 which should have displaced Fl. Key Click to variation 1 for GM support).

Reply 22 of 35, by Cloudschatze

User metadata
Rank Oldbie
Rank
Oldbie
jaffa225man wrote on 2023-03-18, 04:21:

I probably should have consulted you before making this frivolous purchase, as it probably doesn't have that 1.02 IC22 ROM version, and you might already be aware of it.

The last four digits of the serial number seem to loop based on some predetermined counter, and are probably only meaningful concerning production comparisons within the same month or year.

In other words:

ZD83743 < ZE13000 < ZE80482

Unless it was swapped for reasons unknown, the ZE80482 model you just purchased should have CM-500 ROM 1.02. I'd made a few offers on that same unit; alas, the seller wanted more for it than I thought its condition could justify... 😀

But, anyway, it will give me a chance to compare its, hopefully true, General MIDI support to mine's falsely labeled General MIDI support (which has the Sine Wave variation 8 at PC#81, yet not Breath Noise at variation 0 of PC#122 which should have displaced Fl. Key Click to variation 1 for GM support).

I tested all of my CM-500 and CM-300 units after reading your initial account of this, including both earlier and later variants of each (that is, inclusive of those bearing the RLP-3037 and RLP-3170 GS daughterboards, respectively), and was unable to duplicate the behavior. They all produced Breath Noise at CC0 #0, PC #122, and Fl. Key Click at CC0 #1, PC #122. Is the behavior you'd experienced consistently reproducible with your unit?

Reply 23 of 35, by jaffa225man

User metadata
Rank Newbie
Rank
Newbie
Cloudschatze wrote on 2023-03-18, 06:17:
The last four digits of the serial number seem to loop based on some predetermined counter, and are probably only meaningful con […]
Show full quote

The last four digits of the serial number seem to loop based on some predetermined counter, and are probably only meaningful concerning production comparisons within the same month or year.

In other words:

ZD83743 < ZE13000 < ZE80482

Unless it was swapped for reasons unknown, the ZE80482 model you just purchased should have CM-500 ROM 1.02. I'd made a few offers on that same unit; alas, the seller wanted more for it than I thought its condition could justify... 😀

This is a link to the file that I use to decode serial numbers from 1989 and later: http://llamamusic.com/super-jx/Roland_Serial_ … r_1989-2010.pdf.
It's why I favor the model name change reasoning instead of wraparounds, but yes, it could be something like that.

And yes, the condition looks pretty bad, but I'm more interested in trying to solve mysteries than aesthetics. It's possible that it came down in price after being sold in Japan, because after I bought it I searched for "dm-500n-3" and all that came up on google was a more expensive listing of the same unit from a different seller (https://www.ebay.com/itm/404137981802). The other possibility is, I'm being scammed and what I'm being sent is a different unit than pictured, although they are obviously other pictures of the same unit. It's still pricey, but here's the one I bought: https://www.ebay.com/itm/354609719230

Cloudschatze wrote on 2023-03-18, 06:17:

But, anyway, it will give me a chance to compare its, hopefully true, General MIDI support to mine's falsely labeled General MIDI support (which has the Sine Wave variation 8 at PC#81, yet not Breath Noise at variation 0 of PC#122 which should have displaced Fl. Key Click to variation 1 for GM support).

I tested all of my CM-500 and CM-300 units after reading your initial account of this, including both earlier and later variants of each (that is, inclusive of those bearing the RLP-3037 and RLP-3170 GS daughterboards, respectively), and was unable to duplicate the behavior. They all produced Breath Noise at CC0 #0, PC #122, and Fl. Key Click at CC0 #1, PC #122. Is the behavior you'd experienced consistently reproducible with your unit?

Well I feel sheepish. Your suspicion made me check it just now, and sure enough, I do have Breath Noise at variation 0, and Fl. Key Click at variation 1! I was testing using my qmidiroute patch before, too, so I don't know what changed (or more likely, what mistake I was making). Mine contains the RLP-3037, by the way, and is blowing sweet breath sounds at me presently. 😀

Thanks for making me test it again, but that will mean my new unit will only be worse than what I already have! 😉 And that really is fine if we can figure out whatever you think is wrong with version 1.02.

Reply 24 of 35, by Cloudschatze

User metadata
Rank Oldbie
Rank
Oldbie
jaffa225man wrote on 2023-03-18, 20:10:

Well I feel sheepish. Your suspicion made me check it just now, and sure enough, I do have Breath Noise at variation 0, and Fl. Key Click at variation 1! I was testing using my qmidiroute patch before, too, so I don't know what changed (or more likely, what mistake I was making). Mine contains the RLP-3037, by the way, and is blowing sweet breath sounds at me presently. 😀

This is the best outcome. 😀

Thanks for making me test it again, but that will mean my new unit will only be worse than what I already have! 😉 And that really is fine if we can figure out whatever you think is wrong with version 1.02.

It's just the opposite, rather. There's an occasional behavior that I'm experiencing in Mode A with my v1.00 units that is presumably resolved with ROM version 1.02 (based on some vague information I'd received from Roland Japan a couple of decades ago). When you receive your ZE80482 unit, can you please send me a PM for some further discussion? 😀

Reply 25 of 35, by jaffa225man

User metadata
Rank Newbie
Rank
Newbie
Cloudschatze wrote on 2023-03-18, 20:25:

This is the best outcome. 😀

I agree! 😀

It's just the opposite, rather. There's an occasional behavior that I'm experiencing in Mode A with my v1.00 units that is presumably resolved with ROM version 1.02 (based on some vague information I'd received from Roland Japan a couple of decades ago). When you receive your ZE80482 unit, can you please send me a PM for some further discussion? 😀

Definitely, and that's good news, although I haven't had a use for mode A yet (just B & C). I'm glad you haven't forgotten vague details from decades ago!

I noticed an INTEGRA-7 freezing issue and was only able to communicate through an english translator with Roland Japan, so the final verdict wasn't too satisfying:

They are saying that this issue is mostly being caused by using the SuperNatural drum kit in the Integra-7. If the maximum polyp […]
Show full quote

They are saying that this issue is mostly being caused by using the SuperNatural drum kit in the Integra-7. If the maximum polyphony of the SuperNatural drum kit is exceeded, this can cause processing errors, and also the SuperNatural engine apparently uses a lot more processing power than the PCM engine (which is why an older Sound Canvas could play a file like this with no issues since it only uses PCM).

They also said that some DAWs appear to organize the event order differently, so they did not see this issue when using Cubase, Studio One, or Logic.

It appears this is not a bug, but just an overload of processing power in the module, so they had the following suggestions:

- Use a PCM drum kit instead of a SuperNatural drum kit.

- Use a different DAW if possible.

- Filter out the CC#10 pan messages. There are a lot of these and if they are filtered it helps with the processing also.

I would have thought a firmware update could be developed that lightens the load by filtering messages (or buffering and rearranging them). However, I can also imagine musicians would want the INTEGRA-7 to always follow their own exact programming, but this freezing was a bit unreliable to begin with (it took repeated playbacks sometimes). Perhaps they're still working on it, but it has been a couple years since I received that response. Still, I suppose this is all interesting. 😀

Reply 26 of 35, by jaffa225man

User metadata
Rank Newbie
Rank
Newbie
Cloudschatze wrote on 2023-03-18, 20:25:

It's just the opposite, rather. There's an occasional behavior that I'm experiencing in Mode A with my v1.00 units that is presumably resolved with ROM version 1.02 (based on some vague information I'd received from Roland Japan a couple of decades ago). When you receive your ZE80482 unit, can you please send me a PM for some further discussion? 😀

That was the fastest shipping I've had from Japan (three days to Wisconsin, as they waited until Wednesday to send it)! Anyway, PM sent, but I'm not sure its ICC22 is version 1.02. I'm hoping your reply will say it is.

Reply 27 of 35, by AndreStarTrek

User metadata
Rank Newbie
Rank
Newbie
Cloudschatze wrote on 2022-09-19, 21:13:
dormcat wrote on 2022-09-19, 14:50:

This thread has been reported by Japanese tech website Gigazine. 😸

The exposure is welcome, but the accolade should really be directed at Sergey. Also, the article conflates the CM-32L and unmodified CM-32LN for some reason.

For anyone interested in performing this modification, I am willing to send, at my expense, the requisite 8 MHz crystal, IC socket (where needed), and modified ROM IC; just provide me with a shipping address via PM.

I came across this topic and wow this fix is incredible, I have a CM-32LN and like to do this mod. I would not mind doing it my self and been searching for parts on Aliexpress. But i read you can help with sending a kit, I would not mind paying for it. But seen i am new here (I thought i had a account here but i did not) I cant PM you just yet. I hope you can help me out, I am from the netherlands.

Reply 28 of 35, by keropi

User metadata
Rank l33t++
Rank
l33t++
AndreStarTrek wrote on 2023-12-14, 23:05:

I came across this topic and wow this fix is incredible, I have a CM-32LN and like to do this mod. I would not mind doing it my self and been searching for parts on Aliexpress. But i read you can help with sending a kit, I would not mind paying for it. But seen i am new here (I thought i had a account here but i did not) I cant PM you just yet. I hope you can help me out, I am from the netherlands.

I can send you a pre-programmed rom+socket - but I do not think I have a suitable 8mhz xtal
looking at mouser for the Abracon one mentioned by Cloudschatze in the original post it seems it is no longer available but a replacement one is: the ECS-80-18-4X-CKM

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

Reply 29 of 35, by AndreStarTrek

User metadata
Rank Newbie
Rank
Newbie
keropi wrote on 2023-12-15, 06:27:
AndreStarTrek wrote on 2023-12-14, 23:05:

I came across this topic and wow this fix is incredible, I have a CM-32LN and like to do this mod. I would not mind doing it my self and been searching for parts on Aliexpress. But i read you can help with sending a kit, I would not mind paying for it. But seen i am new here (I thought i had a account here but i did not) I cant PM you just yet. I hope you can help me out, I am from the netherlands.

I can send you a pre-programmed rom+socket - but I do not think I have a suitable 8mhz xtal
looking at mouser for the Abracon one mentioned by Cloudschatze in the original post it seems it is no longer available but a replacement one is: the ECS-80-18-4X-CKM

That would be awesome, what would be the cost for this? I beleave i dont need a socket for this unit.

Do i really need that crystal from that brand or should generic crystals also work like this https://nl.aliexpress.com/item/1005006301645381.html, shipping from mouser is pretty expensive, 20,43 for one crystal is a bit excessive.

I would not mind buying the tools and chips, I wanted to have this tool and so on, but I never done it before and dont want to fry the original rom chip while reading 😜. Also i need to know or find out what is a nice chip reader/write, something that is versatile.

Reply 30 of 35, by keropi

User metadata
Rank l33t++
Rank
l33t++
AndreStarTrek wrote on 2023-12-15, 19:58:

That would be awesome, what would be the cost for this? I beleave i dont need a socket for this unit.

Do i really need that crystal from that brand or should generic crystals also work like this https://nl.aliexpress.com/item/1005006301645381.html, shipping from mouser is pretty expensive, 20,43 for one crystal is a bit excessive.

I would not mind buying the tools and chips, I wanted to have this tool and so on, but I never done it before and dont want to fry the original rom chip while reading 😜. Also i need to know or find out what is a nice chip reader/write, something that is versatile.

I don't need any money for an eeprom shipped to NL
these chinese crystals might work OK , might not... there is no telling
maybe I can find a used xtal in my stash and add it to your package, you can try and if you see it does not work then you get some other
the most affordable and good programmers are the XGecu ones , the T48 being the main base model. I can highly recommend it , you can buy at their official aliexpress store: https://xgecu.aliexpress.com/store/4805043?sp … Head_34392563.0

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

Reply 31 of 35, by AndreStarTrek

User metadata
Rank Newbie
Rank
Newbie
keropi wrote on 2023-12-15, 21:07:
I don't need any money for an eeprom shipped to NL these chinese crystals might work OK , might not... there is no telling mayb […]
Show full quote
AndreStarTrek wrote on 2023-12-15, 19:58:

That would be awesome, what would be the cost for this? I beleave i dont need a socket for this unit.

Do i really need that crystal from that brand or should generic crystals also work like this https://nl.aliexpress.com/item/1005006301645381.html, shipping from mouser is pretty expensive, 20,43 for one crystal is a bit excessive.

I would not mind buying the tools and chips, I wanted to have this tool and so on, but I never done it before and dont want to fry the original rom chip while reading 😜. Also i need to know or find out what is a nice chip reader/write, something that is versatile.

I don't need any money for an eeprom shipped to NL
these chinese crystals might work OK , might not... there is no telling
maybe I can find a used xtal in my stash and add it to your package, you can try and if you see it does not work then you get some other
the most affordable and good programmers are the XGecu ones , the T48 being the main base model. I can highly recommend it , you can buy at their official aliexpress store: https://xgecu.aliexpress.com/store/4805043?sp … Head_34392563.0

Thanks that is very kind and love to take you up on your offer and if you find a crystal, that would be awesome. How could i get in touch with you to send you my adress?

I wil also do some research on that programmers, I want one for years, never came around to do it and now I need one and dont have one and also need to learn to use it 🤣.

Last edited by AndreStarTrek on 2023-12-16, 12:33. Edited 1 time in total.

Reply 32 of 35, by rasz_pl

User metadata
Rank l33t
Rank
l33t

There is nothing special about 8MHz quartz crystal needed for this Roland unit. You dont have to worry about origin country, they are made using positively ancient manufacturing process - 50-100 years depending how you look at it with very little change. Even in the seventies poor countries under russian occupation were manufacturing perfectly good components despite huge technological gap.

Open Source AT&T Globalyst/NCR/FIC 486-GAC-2 proprietary Cache Module reproduction

Reply 33 of 35, by keropi

User metadata
Rank l33t++
Rank
l33t++
AndreStarTrek wrote on 2023-12-15, 22:29:

Thanks that is very kind and love to take you up on your offer and if you find a crystal, that would be awesome. How could i get in touch with you to send you my adress?
[...]

I could not find a 8mhz xtal - so I can only send you the eprom if you need it - will send you a PM with my email

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

Reply 34 of 35, by AndreStarTrek

User metadata
Rank Newbie
Rank
Newbie

Yz36C1Y.jpg
Testing
u0OkB9k.jpg
Stored the original components in side the case.

Succes, it works perfectly, I am so happy now. Got this one because the CM-32L was way to expensive, I knew this one had this bug but I got it for a nice price. But alway on the lookout for the CM-32L. But now I have the best CM-32L you can buy, because there almost no noise in from the cm-32ln.

rasz_pl wrote on 2023-12-16, 05:31:

There is nothing special about 8MHz quartz crystal needed for this Roland unit. You dont have to worry about origin country, they are made using positively ancient manufacturing process - 50-100 years depending how you look at it with very little change. Even in the seventies poor countries under russian occupation were manufacturing perfectly good components despite huge technological gap.

I ordered the generic crystals from Aliexpress that i post before and they work perfectly, so indeed notting special and much much cheaper thanks 😉

keropi wrote on 2023-12-18, 07:57:
AndreStarTrek wrote on 2023-12-15, 22:29:

Thanks that is very kind and love to take you up on your offer and if you find a crystal, that would be awesome. How could i get in touch with you to send you my adress?
[...]

I could not find a 8mhz xtal - so I can only send you the eprom if you need it - will send you a PM with my email

Again thank you for sending me the eprom 😀