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ChromaTalk Archives: November 2000

Chroma Problem Still

Kevin Bayer · Thu, 2 Nov 2000 22:32:42 -0800 (PST)

See the previous thread about Kevin's troubles, chroma problem, in the October 2000 archive.

Hello All!
I first want to thank you for all of your kind guidance and support. But I'm sad to report that none worked so far. Here is what I came up with as of now. I tried the staccato notes, and as much as i was hoping it would be this it wasn't.

It is hooked up to my Kurzweil through only Midi-Out and the Kurzweil is Midi-In and that is the only connection and the amp is hooked up in the Kurzweil. When I did the "param select" on all of the 50 Program Selects and then hit each note, the only change I noticed was on the A. No note was played when I hit it. The Err....036 still shows up when I turn the chroma on. If this helps, when I did the Param Selects here were the Paramete and Values: They all were value 0's except the following,

P23...31
P26...12
P39...63
P47...15

Don't know if that helps at all, but any advice from here would be helpful once again. I called Fender, and of course they had no clue, but they gave me a number of a Dayton Musician's center who has someone there that might be able to help. If you all could help me avoid spending money to fix this that would be great, for I am a poor starving college student(ok, not starving)...Thanks a lot again. Take care, Kevin

Chris Ryan [21030691] · Thu, 2 Nov 2000 23:23:36 -0800

If this helps, when I did the Param Selects here were the Paramete and Values: They all were value 0's except the following,

P23...31
P26...12
P39...63
P47...15

These are the default values for those parameters (Envelope 2 Decay, Tune, Cutoff Tune, and Volume Mod 1 Depth, respectively).

The only other thing I can think of is that there is a problem with the contacts for the key in question. Have you opened up the Chroma to take a look?

Don't know if that helps at all, but any advice from here would be helpful once again. I called Fender, and of course they had no clue, but they gave me a number of a Dayton Musician's center who has someone there that might be able to help. If you all could help me avoid spending money to fix this that would be great, for I am a poor starving college student(ok, not starving)...Thanks a lot again. Take care, Kevin

There are some service resources listed on the site, if no one on the list has any other ideas.

Perhaps the most knowledgeable (?) is Peter Miller at CAE Sound.

Chris

David Clarke [21030085++] · Sun, 5 Nov 2000 14:46:44 -0500

It is hooked up to my Kurzweil through only Midi-Out and the Kurzweil is Midi-In and that is the only connection and the amp is hooked up in the Kurzweil. When I ...hit each note, the only change I noticed was on the A. No note was played when I hit it.

I agree with Chris Ryan - the most likely problem with the 'A' is something has gone awry with the key contact for that note. If you take the top off the Chroma (and flip up the control panel) you'll have full access to all the keys. You can then watch what happens when you press bad key (versus the other keys which work). If you're lucky, you might just have to make a small mechanical adjustment.

The Err....036 still shows up when I turn the chroma on.

This message means that 3 of the 8 voice boards are failing the auto-tune. If you open the Chroma (to look at the key contacts), you may wish to reseat all 8 voice cards. The next step after that would be a check-out of the voltages coming from the power supply - the DAC setup and then standard trouble-shooting with an oscilloscope to see why those 3 boards are not tuning properly.

Good Luck,

David Clarke

Kevin Bayer · Sun, 5 Nov 2000 18:56:26 -0800 (PST)

How exactly do I reset the voicecards when I open the chroma up??? I have it open and the key contact looks good so I want to reset the voice cards but I have no idea how to go about doing that??? any help??? kevin

David Clarke [21030085++] · Sun, 5 Nov 2000 22:46:01 -0500

How exactly do I reset the voicecards when I open the chroma up???

There is no 'reset' on the cards; however, just re-seating them (i.e., removing the card and making sure it was installed correctly - and the connector/pins are OK) is sometimes enough to get the cards to work.

To do this remove the two small braces across the top of the voice boards (approx 1/2" wide x 6" long). Then, to remove the cards, just pull them straight up. Once they're out - you can make sure the connectors on the bottom of the cards look OK - and the pins below are clean (and un-bent).

I have it open and the key contact looks good

Take a really close look - the individual parts of the contacts on the bad 'A' should open/close just like the keys beside it. If one part of the contact stays shut (or never closes) then that would explain why that one key doesn't work.

Good Luck,

Dave

David Clarke [21030085++] · Mon, 6 Nov 2000 18:51:51 -0500

From: Dave Bradley [I'm missing Dave Bradley's original post which David Clarke quotes here--Chris]

It may also be instructive to reset the computer and force it to enable the bad boards. You'll either hear 3 voices somewhat out of tune, or something really bad that points elsewhere.

I once had a voice that wouldn't tune up, and turning it on revealed that the VCOs were fine, it was the VCF that was failing. Turned out to be a bad bypass cap on the voice board.

Somebody correct me if I'm wrong, but I believe that the command for a computer reset without bad board muting is Set Split 31?

... confirmed. Set Split 31 will do the tune, but will ignore any channels that malfunction.

David Clarke

Phil Dodds interview

Dave Bradley [16330135] · Mon, 6 Nov 2000 13:42:25 -0600

What's the status of the Dodds interview?

Chris Ryan [21030691] · Mon, 6 Nov 2000 12:19:44 -0800

Coincidentally, I e-mailed him yesterday and I heard back from him this morning: he has some time to get back to it. I expect (hope) to post something in the not too distant future.

On a related note, I heard from Tony Williams (one of the designers of the Chroma, and the author of the Apple II and IBM PC sequencer software) a couple of months back. He still works with Paul DeRocco (the chief engineer), and seemed to be open to the idea of a similar "interview." Any interest? I'm sure we could get some of our more technical questions answered. (And I don't think it would take as long as the Dodds interview.)

Dave Bradley [16330135] · Mon, 6 Nov 2000 14:24:13 -0600

Sure! Send him the exact same questions as Phil, then publish both their answers to each question together later.

David Clarke [21030085++] · Mon, 6 Nov 2000 19:13:38 -0500

Coincidentally, I e-mailed him yesterday and I heard back from him this morning: he has some time to get back to it. I expect (hope) to post something in the not too distant future.

Good news! (I had actually forgot that we were still waiting!)

On a related note, I heard from Tony Williams (one of the designers of the Chroma, and the author of the Apple II and IBM PC sequencer software) a couple of months back. He still works with Paul DeRocco (the chief engineer), and seemed to be open to the idea of a similar "interview." Any interest?

Definitely. As suggested by Dave Bradley, I think it would be a good idea to submit the same questions to them - that way we'd get to see if everyone had the same understanding of the project.

Also, since these fellows would likely have had greater hands-on knowledge I'm sure we could come up with a few more technical questions for them.

The interview was finally complete and posted in 2002: see Philip Dodds/Tony Williams Interview.

Problem with patches

Go to first message in thread (June 2000)

Dave Bradley [16330135] · Mon, 6 Nov 2000 15:00:26 -0600

I have downloaded the factory patches for the Chroma, I've converted it in the .snd (tape) format, but I'm not able to listen it or send it to the Chroma by the tape interface. It's strange that if I convert the tape format in the txt one, all seems to be ok, but if I try to open it with Windows Media Player, it tell me "the format is not supported".

I'm having this exact same problem: I can't play back the .SND file. Can anybody help with a Windows player known to work? I've tried Windows Media Player, Media Jukebox, and WinAmp so far.

David Clarke [21030085++] · Mon, 6 Nov 2000 18:57:22 -0500

CoolEdit and GoldWave should both work OK. Actually, any program that will let you read RAW audio files should do just fine.

Status: Windows interface to Chroma

Mark R. David [21030170+] · Tue, 14 Nov 2000 16:25:01 -0500

I've (finally!) completed and tested a circuit that works for this project. Details on the web at: [obsolete URL removed]

All that's left now is programming, which I'm much better at than circuit design. (Well, I still have to move the circuit from breadboard to wire-wrap, but I'm putting that off as long as possible.) The Server Object Library will come next, hopefully by end of year.

See Windows Editors & Librarians: Windows Interface for Chroma for links to related threads.

voice patches

Ray Hannisian [21030829] · Wed, 15 Nov 2000 12:05:46 +0000

I downloaded some Chroma Cult voice patches from the Chroma web-site. What is the most direct means of moving those voices to cassette tape for my loading into my synth?

(I have the downloaded patches on both my MAC and PC. I also have an Apple IIe connected to my Chroma, with the capability of saving voices onto 5.25" floppies.)

Dave Bradley [16330135] · Wed, 15 Nov 2000 13:19:02 -0600

Turn them into .wav files using the utilities on the Conversion Tools page.

Play on your computer's soundcard, and either record them to cassette, or try hooking the soundcard output directly to the Chroma, by making a cable with the DIN plug on one end.

Dave Bradley [16330135] · Wed, 15 Nov 2000 13:30:59 -0600

Actually, the utilities can give you .snd files, not .wav files. I couldn't find a Windows player that would play .snd files, so I found a shareware converter that turned them into .wav files.

Chroma service in the UK???

Paul Hackett-Evans [21010094] · Wed, 22 Nov 2000 00:35:06 -0000

Hi,
My Chroma has been on semi-permanent loan to a friend who lives 150 miles from me for 10 years. I'm just about to go get it back and I need to get it serviced (Power supply blues....) I'll post its history on the site once I can remember the serial number. I'm really keen to update the power supply to the nuclear powered Chroma, if there's a British voltage equivalent switching PSU. Does anyone know if there is and any details please?

Also, does anyone have a contact address/phone number for a Chroma service engineer in the UK?

My Chroma was serviced in 1989 by a really good guy called Roy Paynter, he did a super job, but I don't have his details anymore, other than he worked from Stevenage, Hertfordshire. That isn't enough to trace him, does anyone know where he is now? Or another good Chroma repairer?

Thanks
Paul

Don Tillman · Tue, 21 Nov 2000 17:20:25 -0800 (PST)

Hi.

The power supply in my "Nuclear Powered Chroma" handles international voltage sources, switching automatically. (Not that I've tried out that feature yet.)

That's a really great feature of switching power supplies.

-- Don

-- Don Tillman
Palo Alto, California, USA
http://www.till.com

Paul Hackett-Evans [21010094] · Thu, 23 Nov 2000 22:02:38 -0000

Nuclear Chroma PSU

Hi Again,
Don gave me the answer to the UK voltage query - the switching PSU automatically adjusts for international voltages, thanks Don! Can the gent who was offering to build the PCB and the PSU for others please get in touch? I really want one if I can get it! Looking forward to hearing from you!
Regards
Paul