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ChromaTalk Archives: April 2005

EES MIDI Kit Documentation

Chris Ryan [21030691] · Fri, 1 Apr 2005 07:20:30 -0800

I've added EES MIDI Kit Documentation to the site, with pictures and translation by Jesper Ödemark.

Thanks, Jesper!

Chroma on eBay (some sell, some don't)

David Clarke [21030085++] · Sat, 02 Apr 2005 11:16:58 -0500

Go to first message in thread (March 2005)

Chris Ryan wrote:

Serial number 21030825 [1], eBay item 7311739621. "Mint" condition; includes standard accessories and an unspecified MIDI kit. No bids yet; first bid US$1000 ...

It's funny - I see that this keyboard is now sitting at about 1500US, and has 9 bids on it (after only being listed for a day+).

The other Chroma that's been up on Ebay a couple times recently (the one from Australia) appears to work out to cheaper than that (even with overseas shipping) - and I haven't yet seen an offer on it ...

Luigi Castelli [21030825] · Sun, 3 Apr 2005 12:05:21 -0700

Chroma on eBay

Hello,

I am the owner of the Chroma on sale on eBay. I wanted to apologize for not putting a reference to www.rhodeschroma.com in my auction.

My oversight has been fixed.

Thank you and please feel free to contact me if you need any info on my Fender Chroma or are interested in purchasing it.

Best.

Walt Whitney Patch Tape on eBay

Chris Ryan [21030691] · Tue, 12 Apr 2005 19:33:12 -0700

Someone has a cassette tape of Walt Whitney's sounds for sale. Walt advertised his sounds on the site a number of years ago; I bought a copy but still haven't got around to loading them into my Chroma. They were all original; Walt wrote in 1999, "they are great patches, a good mix of useful stuff."

Item 7314355374. Starting bid is US$5.

Note that Walt Whitney since agreed to release his patches into the public domain; they are now available from the Patch Downloads page.

Vincent Russo [21030433] · Tue, 12 Apr 2005 22:45:55 -0400

perhaps whomever buys it could kindly load it in sysex to the site for everyone to try ??

Chris Ryan [21030691] · Tue, 12 Apr 2005 21:52:12 -0700

I was going to do that, but as they were commercially available patches, didn't think it would be kosher. I'm not sure of Walt's status now, though, or whether he would be OK with having them freely distributed.

David Gowin [21030611] · Wed, 13 Apr 2005 09:43:53 -0400

Am not sure if the other bidder(s) are from the group, but I've put my bids in, we shall see what happens!

Jesper Ödemark [21010135] · Wed, 13 Apr 2005 16:57:59 +0200

Or we viciously send a few cents each and buys it together and the poor seller won't see any bidding! ;)

Vincent Russo [21030433] · Wed, 13 Apr 2005 11:05:43 -0400

If the bidding goes a little higher I can make up the difference to the bidder as long as they promise to share with everyone. Just let me know.

Kevin Kelley [21030491+] · Wed, 13 Apr 2005 08:11:54 -0700

I am in as well, I would love to see more patch sets posted on the site for download.

David Gowin [21030611] · Wed, 13 Apr 2005 11:33:51 -0400

Kevin, I definitely don't want to turn this into a bid war if the tape will eventually benefit the group. So if you're high bidder right now and have good intentions for the tape, I won't counter bid

David Gowin [21030611] · Wed, 13 Apr 2005 11:37:58 -0400

Doh! Sorry Kevin, when I read "I am in as well" I thought you were bidding on the tape. My apologies.

Chris Ryan [21030691] · Wed, 13 Apr 2005 08:44:09 -0700

I will post the patches to the site if someone obtains the author's permission.

Paul Tillotson [21030218] · Wed, 13 Apr 2005 09:03:39 -0700

And I plan on doing the same, if I win the bidding, but have not been able to contact Mr Witney in several years, which is how long I've been trying to aquire this data tape. This means you should let "Gablelomb" win the bidding...

David Gowin [21030611] · Wed, 13 Apr 2005 13:18:58 -0400

No problem, won't bid again, good luck!

Chris Ryan [21030691] · Wed, 13 Apr 2005 10:45:32 -0700

And I plan on doing the same, if I win the bidding, but have not been able to contact Mr Witney in several years, which is how long I've been trying to aquire this data tape. This means you should let "Gablelomb" win the bidding...

Just to be clear, although I've tried to maintain the site as an "open" space and accept contributions with gratitude, I remain the only person who can make any additions or modifications. I've tried to be quite rigourous in obtaining permission to post articles and files. I've had Walt's tape for several years: I purchased it from him and he specifically asked me not to make the sounds freely available.

That said, while I would hope that you would obtain permission to circulate the patches by other means--including this mailing list--I certainly can't or won't stop you (although I probably wouldn't include the file in the list archives). I suppose it's something of a grey area since you're buying it "no strings attached" from a third party, but as I was in touch with Walt about this I hope you'll understand my position. Perhaps I'll try to track him down again--or if someone else wants to, I'd appreciate it.

Vincent Russo [21030433] · Wed, 13 Apr 2005 13:56:17 -0400

Walt does not make mention of his Chroma patches here, but i have emailed him to see if its Ok or if he still out there.

http://www.whitneycreative.com/id2.html [domain gone as of 2009.07]

Does not seem like hes too active any longer

Chris Ryan [21030691] · Wed, 13 Apr 2005 11:13:06 -0700

Thanks, Vincent. If Walt gives permission, the auction is moot--I have the tape and will convert the sounds for all.

Paul Tillotson [21030218] · Wed, 13 Apr 2005 16:58:01 -0700

And I fully concur that Mr Ryan's great site should not be the type of place where members violate copyright laws or deprive talented programmers of their well deserved living...sorry for any misunderstanding.

Chris Ryan [21030691] · Wed, 13 Apr 2005 17:20:49 -0700

No problem. Perhaps there's some confusion between the site and the list. I "own" both: I do all work and maintenance on the site, and I'm mailing list administrator. Currently the list is hosted (free of charge!) at synthcom.com by Neil Bradley, though I'm the list owner. Perhaps some day I'll move it to rhodeschroma.com; I think my latest hosting company, to which I shifted when I created the domain in January, offers a mailing list as part of the deal.

I have encountered only one copyright issue in the 6+ years the site has been up (a photographer objected to my inclusion of some of her photos from the Rise and Fall of ARP article, which I removed). As it generates no revenue, and costs me to host, I want to avoid any issues.

Olli [21010284] · Thu, 14 Apr 2005 16:37:43 +0200

i wonder what the copyright situation is, when a product is no longer vailable...

Murray Macdonald [21030276+] · Thu, 14 Apr 2005 11:39:19 -0700

Copyright last 75 years past the death of the author. Lennon's songs still make money for Mr Jackson.

Jim Russo [21030433] · Thu, 14 Apr 2005 16:04:51 -0400

Knowing copyright and trademark law very well myself, that is only valid if the if the entity is still active. Were talking about sounds done over 20 years ago that are no longer for sale, by someone apparently no longer active in the music industry.

Olli [21010284] · Thu, 14 Apr 2005 22:34:10 +0200

so probably fallen in the public domain?

Rob Johnson · Thu, 14 Apr 2005 13:55:34 -0700

Of course we are also talking about U.S. Copyright law... Which may or may not apply depending on where you are in the world. Not everyone in the world has the same opinions on IP as we uptight (IMO) Americans do. Although since the servers are in the U.S. it makes good sense that you follow U.S. law. Of course the bigger reason is what Chris has already stated which is we need to respect Walt and his wishes.

Has anyone considered trying to "buy out" the rights to these patches if copyright is an issue here? I noticed Walt (who I have spoken with many years ago and remember him to be a very nice guy) is still selling patches for other synths @ $25 per set. If his patches really are that good and everyone wants them why not offer say $500 (whatever makes sense) to Walt to make the publicly available? We all know that the number of sales he could get is severely limited by the number of Chromas that exist. Take up a collection on the list to buy them and gift it to the Chroma user community.

One last thing... =) with all this interest in patches why are we all not writing some new sets to share with the group? (before you ask... It's already on my "to do" list ;)

Chris Ryan [21030691] · Thu, 14 Apr 2005 15:27:38 -0700

Of course we are also talking about U.S. Copyright law... Which may or may not apply depending on where you are in the world. Not everyone in the world has the same opinions on IP as we uptight (IMO) Americans do. Although since the servers are in the U.S. it makes good sense that you follow U.S. law.

Actually, the servers are--as far as I know, anyway--right here in beautiful Vancouver, B.C., Canada (where we are slightly less uptight on IP but as I'm not a lawyer can't comment on this case).

Has anyone considered trying to "buy out" the rights to these patches if copyright is an issue here? I noticed Walt (who I have spoken with many years ago and remember him to be a very nice guy) is still selling patches for other synths @ $25 per set. If his patches really are that good and everyone wants them why not offer say $500 (whatever makes sense) to Walt to make the publicly available? We all know that the number of sales he could get is severely limited by the number of Chromas that exist. Take up a collection on the list to buy them and gift it to the Chroma user community.

Great idea. If we hear back from Walt, perhaps we should suggest this. There are over 80 people on the list, so US$500 probably wouldn't be difficult to collect.

One last thing... =) with all this interest in patches why are we all not writing some new sets to share with the group? (before you ask... It's already on my "to do" list ;)

When I started the site, I thought that patch sharing would be the biggest draw! There was a thread along these lines a couple of years ago, but David Clarke was the only contributor.

I'll post any and all original patches sent to me.

Paul Hackett-Evans [21010094] · Fri, 15 Apr 2005 14:18:28 +0100

Hi Chris,

I'd be up for contributing towards the cost of the sound bank, if they are good, usable sounds.

Did you manage to make use of patch file I sent you?

Chris Ryan [21030691] · Fri, 15 Apr 2005 23:34:52 -0700

Paul's Patch

Did you manage to make use of patch file I sent you?

I haven't had time to try to load the MIDI file into my Chroma, but I've just now added it to the site, along with the sample. [See Patch Downloads: Paul Hackett-Evans.]

If anyone can save it back out as a sysex file, please send it on and I'll post that as well.

Thanks Paul--it's a nice sound.

David Clarke [21030085++] · Sat, 16 Apr 2005 09:57:06 -0400

Paul's Patch - sysex

Folks, the original MIDI file had just a single patch contained in it.

Attached is a SYSEX of that patch. This is set up so that if you download it, the sound goes into Program 0 (i.e., the current working patch).

David Clarke [21030085++] · Sat, 16 Apr 2005 10:27:19 -0400

Paul's Patch - Patch Params

Following up to my earlier post - if there is anyone who can't use the syxex file but will wanted to try the patch - attached is a text-dump of the patch parameters (so they could be entered by hand). 

Control - Patch (Param 1) 13 Var. Mix Filt. Mode - No Cross Mod
Control - FSW Mode (Param 2) 0 Left: Latch Right: Sustain
Control - Kybd Alg (Param 3) 0 Poly - Polyphonic
Control - Detune (Param 4) 3 0 = No Detune, 1 = Sharp, 31 = More Sharp
Control - Out. Sel (Param 5) 0 Output 0
A - Glide Rate (Param 6) 0 0 = None, 1 = Fast, 31 = Slow
A - Glide Shape (Param 7) 0 Portamento
A - Sweep Mode (Param 8) 0 Asynchronous Free-Run
A - Sweep Rate (Param 9) 45 0 = Slow, 63 = Fast
A - Sweep Rate Mod (Param 10) 0 None
A - Sweep Wave Shape (Param 11) 0 Sine
A - Sweep Ampl Mod (Param 12) 11 Lever 2
A - Env 1 Ampl Touch (Param 13) 3 Medium
A - Env 1 Attack (Param 14) 0 0 = Instant, 1 = Fast, 31 = Slow
A - Env 1 Attack Mod (Param 15) 0 None
A - Env 1 Decay (Param 16) 20 0 = Instant, 1 = Fast, 30 = Slow, 31 = Infinite
A - Env 1 Decay Mod (Param 17) 0 None
A - Env 1 Release (Param 18) 18 0 = Instant, 1 = Fast, 30 = Slow, 31 = Thresh
A - Env 2 Delay (Param 19) 0 0 = None, 1 = Short, 30 = Long, 31 = Retrig on SWP A
A - Env 2 Ampl Touch (Param 20) 3 Medium
A - Env 2 Attack (Param 21) 0 0 = Instant, 1 = Fast, 31 = Slow
A - Env 2 Attack Mod (Param 22) 0 None
A - Env 2 Decay (Param 23) 9 0 = Instant, 1 = Fast, 30 = Slow, 31 = Infinite
A - Env 2 Decay Mod (Param 24) 3 KYBD
A - Env 2 Release (Param 25) 18 0 = Instant, 1 = Fast, 30 = Slow, 31 = Thresh
A - Pitch Tune (Param 26) 12 0 = Low, 12 = Concert, 63 = High
A - Pitch Mod 1 Sel. (Param 27) 3 ENV 2A
A - Pitch Mod 1 Depth(Param 28) 1 -64 = -Deep, 0 = None, 63 = Deep
A - Pitch Mod 2 Sel. (Param 29) 1 Sweep A
A - Pitch Mod 2 Depth(Param 30) 4 -64 = -Deep, 0 = None, 63 = Deep
A - Pitch Mod 3 Sel. (Param 31) 8 Lever 1
A - Pitch Mod 3 Depth(Param 32) 2 -64 = -Deep, 0 = None, 63 = Deep
A - Waveshape Select (Param 33) 0 0=Sawtooth, 1=Pulse, 2=Pink Noise, 3=White Noise
A - Waveshape Width (Param 34) 8 0=Normal, 1=Slight, 32=Greatly, 63=Slight
A - Waveshape Mod Sel(Param 35) 3 ENV 2A
A - Wveshpe Mod Depth(Param 36) 1 -64 = -Deep, 0 = None, 63 = Deep
A - Cutoff LP/HP (Param 37) 0 0 = Low Pass, 1 = High Pass
A - Cutoff Resonance (Param 38) 2 0 = Min Res., 7 = Max Res.
A - Cutoff Tune (Param 39) 27 0 = Low Freq., 63 = High Freq.
A - Cutoff Mod 1 Sel (Param 40) 0 KYBD Glide A
A - Cutoff Mod 1 Dpth(Param 41) 32 -64 = -Deep, 0 = None, 63 = Deep
A - Cutoff Mod 2 Sel (Param 42) 3 ENV 2A
A - Cutoff Mod 2 Dpth(Param 43) 35 -64 = -Deep, 0 = None, 63 = Deep
A - Cutoff Mod 3 Sel (Param 44) 7 ENV 2B
A - Cutoff Mod 3 Dpth(Param 45) 0 -64 = -Deep, 0 = None, 63 = Deep
A - Volume Mod 1 Sel (Param 46) 1 ENV 2A
A - Volume Mod 1 Dpth(Param 47) 15 0 = None, 15 = Deep
A - Volume Mod 2 Sel (Param 48) 3 ENV 2B
A - Volume Mod 2 Dpth(Param 49) 15 0 = None, 15 = Deep
A - Volume Mod 3 Sel (Param 50) 0 None
B - Glide Rate (Param 6) 0 0 = None, 1 = Fast, 31 = Slow
B - Glide Shape (Param 7) 0 Portamento
B - Sweep Mode (Param 8) 0 Asynchronous Free-Run
B - Sweep Rate (Param 9) 45 0 = Slow, 63 = Fast
B - Sweep Rate Mod (Param 10) 0 None
B - Sweep Wave Shape (Param 11) 0 Sine
B - Sweep Ampl Mod (Param 12) 11 Lever 2
B - Env 1 Ampl Touch (Param 13) 3 Medium
B - Env 1 Attack (Param 14) 0 0 = Instant, 1 = Fast, 31 = Slow
B - Env 1 Attack Mod (Param 15) 0 None
B - Env 1 Decay (Param 16) 20 0 = Instant, 1 = Fast, 30 = Slow, 31 = Infinite
B - Env 1 Decay Mod (Param 17) 0 None
B - Env 1 Release (Param 18) 18 0 = Instant, 1 = Fast, 30 = Slow, 31 = Thresh
B - Env 2 Delay (Param 19) 0 0 = None, 1 = Short, 30 = Long, 31 = Retrig on SWP A
B - Env 2 Ampl Touch (Param 20) 3 Medium
B - Env 2 Attack (Param 21) 0 0 = Instant, 1 = Fast, 31 = Slow
B - Env 2 Attack Mod (Param 22) 0 None
B - Env 2 Decay (Param 23) 23 0 = Instant, 1 = Fast, 30 = Slow, 31 = Infinite
B - Env 2 Decay Mod (Param 24) 2 -KYBD
B - Env 2 Release (Param 25) 18 0 = Instant, 1 = Fast, 30 = Slow, 31 = Thresh
B - Pitch Tune (Param 26) 12 0 = Low, 12 = Concert, 63 = High
B - Pitch Mod 1 Sel. (Param 27) 3 ENV 2A
B - Pitch Mod 1 Depth(Param 28) 0 -64 = -Deep, 0 = None, 63 = Deep
B - Pitch Mod 2 Sel. (Param 29) 5 Sweep B
B - Pitch Mod 2 Depth(Param 30) -2 -64 = -Deep, 0 = None, 63 = Deep
B - Pitch Mod 3 Sel. (Param 31) 8 Lever 1
B - Pitch Mod 3 Depth(Param 32) 2 -64 = -Deep, 0 = None, 63 = Deep
B - Waveshape Select (Param 33) 0 0=Sawtooth, 1=Pulse, 2=Pink Noise, 3=White Noise
B - Waveshape Width (Param 34) 8 0=Normal, 1=Slight, 32=Greatly, 63=Slight
B - Waveshape Mod Sel(Param 35) 3 ENV 2A
B - Wveshpe Mod Depth(Param 36) 0 -64 = -Deep, 0 = None, 63 = Deep
B - Cutoff LP/HP (Param 37) 0 0 = Low Pass, 1 = High Pass
B - Cutoff Resonance (Param 38) 2 0 = Min Res., 7 = Max Res.
B - Cutoff Tune (Param 39) 27 0 = Low Freq., 63 = High Freq.
B - Cutoff Mod 1 Sel (Param 40) 0 KYBD Glide A
B - Cutoff Mod 1 Dpth(Param 41) 32 -64 = -Deep, 0 = None, 63 = Deep
B - Cutoff Mod 2 Sel (Param 42) 3 ENV 2A
B - Cutoff Mod 2 Dpth(Param 43) 41 -64 = -Deep, 0 = None, 63 = Deep
B - Cutoff Mod 3 Sel (Param 44) 7 ENV 2B
B - Cutoff Mod 3 Dpth(Param 45) 0 -64 = -Deep, 0 = None, 63 = Deep
B - Volume Mod 1 Sel (Param 46) 0 ENV 1A
B - Volume Mod 1 Dpth(Param 47) 15 0 = None, 15 = Deep
B - Volume Mod 2 Sel (Param 48) 2 ENV 1B
B - Volume Mod 2 Dpth(Param 49) 15 0 = None, 15 = Deep
B - Volume Mod 3 Sel (Param 50) 0 None
Panel - Edit Mode 3 Edit Both
Panel - Edit Program 16 
Panel - Link Balance 0 
Panel - Link Type 0 No Link
Panel - Link Program 36 
Panel - Keyboard Split 4 
Panel - Main Transpose Type 0 No Transpose
Panel - Link Transpose Type 1 Up 1 Octave
Panel - Sequence Program Number 5

Jim Russo [21030433] · Sun, 17 Apr 2005 10:27:29 -0400

Re: Paul's Patch

A very nice sound and great example of the type of thing the Chroma does really well!!!

polaris on german ebay

Jesper Ödemark [21010135] · Sun, 17 Apr 2005 17:25:49 +0200

[Item 7315944165]

Chroma article at Wikipedia

Chris Ryan [21030691] · Sun, 17 Apr 2005 17:57:18 -0700

Just noticed this stub article at wikipedia.org:

http://en.wikipedia.org/wiki/ARP_Chroma

Anyone want to take a shot at expanding/correcting it?

David Clarke [21030085++] · Tue, 19 Apr 2005 18:22:51 -0400

I just took a quick peek and while a bit brief, to me it didn't seem too bad.

Chris Ryan [21030691] · Tue, 19 Apr 2005 15:59:51 -0700

You're right; I was being too picky. It's not that bad, but there are a few questionable details (was it really an "ARP" Chroma? Did the DX-7 actually "copy" the panel design? Why was the Chroma actually discontinued? It seems to have sold reasonable well) and has an odd choice of link to the site. Maybe it's best if it just links to the site, but most Wikipedia articles are more comprehensive (this one is called a "stub").

Ron Joseph [21030042+] · Tue, 19 Apr 2005 23:55:34 +0000

Chroma article at Wikipedia and minutia

The wikipedia article states that the Chroma had the first velocity/pressure sensitive keyboard. (or something similiar). The CS-80 obviously had it previously but does anyone know who had the first?

On a non related subject I finally got my Chroma fixed. Since April of 2004 I've been working on getting the parts for the power supply upgrade. The guys at Cantos music in Canada did an amazing job. Decided I liked Don's lighter color scheme and told them to "follow their muse" and create something unique w/ the woodwork. (They sent pictures of the finished Chromato Chris w/ my permission to post)).

Just getting to know her but I noticed that my Chroma has the parameter button #2 that reads Poly/Mono and has no grill. Since mine has the Arp voice boards and a low serial # maybe the first 50 had a differnt scheme for the front panel. Another abberation is that the top key on the keyboard is white whereas the rest of the keyboard is Ivory. John L. at Cantos said that another Chroma #0023? also had the white key at the top of the keyboard. Any ideas anyone? I'd love to have a matching ivory set..:)

Chris Ryan [21030691] · Tue, 19 Apr 2005 19:14:50 -0700

Re: Chroma article at Wikipedia and minutia

On a non related subject I finally got my Chroma fixed. Since April of 2004 I've been working on getting the parts for the power supply upgrade. The guys at Cantos music in Canada did an amazing job. Decided I liked Don's lighter color scheme and told them to "follow their muse" and create something unique w/ the woodwork. (They sent pictures of the finished Chromato Chris w/ my permission to post)).

I've added John Leimseider's notes and photo to the registry entry for Ron's Chroma [21030042].

The light colour scheme really changes the appearance of the instrument!

Jesper Ödemark [21010135] · Wed, 20 Apr 2005 08:08:30 +0200

Re: Chroma article at Wikipedia and minutia

Damn beautiful result on the wood!

Olli [21010284] · Fri, 22 Apr 2005 21:01:45 +0200

Re: Chroma article at Wikipedia and minutia

whow... this wood is incredible... i would be tempted if there were a wood kit...

Jesper Ödemark [21010135] · Sat, 23 Apr 2005 16:33:10 +0200

Re: Chroma article at Wikipedia and minutia

Slightly off-topic here, but do check my customised Oberheim SEM on my site for some swedish pine;

http://www.electronic-obsession.se/studio/sem/sem.html

I have a Korg MS-10 that's had the same treatment (the keyboard was, I like to point out, not worth saving);

http://www.electronic-obsession.se/studio/ms10/img_3777.jpg

Luca Sasdelli [21010226] · Tue, 26 Apr 2005 11:12:35 +0200

Hi Chris,

I've set up an article on italian site http://it.wikipedia.org

See Chroma article (in Italian, of course).

Chris Ryan [21030691] · Tue, 26 Apr 2005 21:46:15 -0700

Excellent! (full URL is http://it.wikipedia.org/wiki/Chroma)

Chroma power supply odyssey

Jimmy Moyer [21030184] · Fri, 22 Apr 2005 21:17:48 EDT

Thought I'd update you all on recent power supply travails I've had. (A story with a happy ending, in case you don't make it through to the end.)

A couple of months back my Chroma failed to turn on - no display, no indication of any activity. I opened it up and found essentially nothing coming from the pre-regulator. DC coming from the rectifiers was OK and it looked like the 120Hz oscillator was running. I also checked that it wasn't simply the over-voltage protector pulling down the output, as happened to me a year or so back. There were no visible signs of anything burnt. (Well, there was one. My transformer has given off a distinct burnt smell, but that for many years and it seems to be still working OK.)

Given that it looked like the power supply needed to come out, it seemed like a good idea to embark on the detailed upgrade described by Martin Straw on the site. It wasn't hard or very expensive to get the parts together to replace all the transistors and upgrade the various resistors, etc.

One thing I noted, but thought little of at the time, was that there was a fine coating of a white powder substance on parts of the board, more so on the bottom and towards the back panel. I cleaned the whole board off with alcohol and a toothbrush before starting. I started replacing components from the inside of the board, just easier to get at them there and this started smoothly. Unfortunately, the real bad news is that as I progressed I found traces lifting off the board and easily broken. Over near the power transistors, I found I could lift traces from the board with my fingernail. This was not going to be a reliable upgrade. I'm now guessing that the white powder I'd found was something chemically leached from the board in response to 22+ years of heat.

Abandoning Plan A, Plan B looks like Don Tillman's plans for replacing the whole power supply with a new one off the shelf, "Nuclear-powered Chroma". The Power-One supply he used is still available. No trouble constructing a small perf-board with the power fail signal buffer and outboard analog 5V supply. No trouble constructing the power supply to Molex plug adaptor harness. I put together a dummy resistor load so I could check (and double and triple check) all the output voltages. Following Martin Shaw's direction, I adjusted my +12 supply to precisely match the -12 supply which is not adjustable on the new supply. They're now +/-11.85V. I also elected to make my new 5V analog supply adjustable and set it to 5.05V per the service manual.

[Ignoring the 'If-you-finish-finicky-work-at-2AM-you-should-sleep-and-recheck-before-applying-power.' rule.]

Plugged the Chroma in and tuned it on. Got all voice errors 01234567 on the display, but other wise the display and front panel were working OK. After about 5 seconds of this following the burning smell followed by wisp of smoke I shut it off. I found what was burning was the main DAC chip. I pretty quickly also discovered that I'd neglected to reattach the green ground wire from the Channel Motherboard to the back panel. It appears to me now as if this is no safety ground, but the only ground return for all the analog circuits on voice cards. Lacking this, water found its lowest level, back through the DAC. Ouch. [I guess we'll never know why there's no ground for the analog supplies on the power plug to the channel motherboard, though there's an empty pin where one could go.]

Tried power again after connecting that ground wire. Still all errors on start up, but no smoke. Listening to the failed channels, I can hear vague resemblances to what the patches ought to be. The oscillators are running. I can open and close the filters and amps, at least partly. But the tuning is a mess and each voice seems never to silence, but drones on in the background. So, the DAC is now probably far from linear?

A replacement DAC is readily available. About $12 from Digikey. It comes a few days later. The old one is even socketed so the I/O board does not even have to come out.

Now I get the flashing lights during power up autotune and NO ERRORS! Yes! The output sounds fine and everything seems to be working. I retest and retweak all the power supply voltages. I think it seems smart to test the digital +5 all the way out on the end of the memory chips on the CPU board and adjust for 5.00V there or about 5.1V back at the supply. I noted the outboard regulator for the 5V analog supply gets quickly too hot to touch so I put a standalone heatsink on that.

One last thing is to connect my Syntech MIDI interface and recheck the supply voltages. Again good advice from Martin Straw. But what happens when I power the Chroma up the Syntech attached is lockup as soon as autotune is complete. Pull it off and now OK. Plug it back in and locked up again. Hmmm... This seems vaguely familiar to me. What I rediscover is that for some reason, at least the combo of my Chroma and my Syntech interface like the 5V digital supply to be low. It starts to work around 5.02V, but as things heat up over the first couple of hours this point droops. I've left it set at 4.97V measured at the supply.

That was now more that two weeks ago and I've used the Chroma most days. On a couple of occasions I left it running for 12+ hours straight to no ill effects. Heat does still build up, but nothing like the old supply. Though there's not room to bolt the new supply to the back panel, I am going to look at getting a piece of aluminum stock to bolt in between. As Don points out in his article, the Chroma is a little lighter and better balanced, so easier to handle. Don also noted an acoustic buzzing with his original supply. Mine did this too. Seems to me now this is inherent in the pre-regulator loading and unloading the transformer at 120Hz. [Does everybody's Chroma buzz?] The new supply is dead silent. Now I notice a tiny whine from the display backlight on my Wavestation A/D sitting atop the Chroma. Never heard that before. I don't miss the burning transformer smell either.

My thanks to Martin and Don for all their advance work. Now back to music.

Well, one last warning I had to ignore. The docs with the Power-One supply clearly state, "Power-One products are not authorized for use as critical components in nuclear control systems without the express written consent of the divisional President of Power-One, Inc."

Jesper Ödemark [21010135] · Sat, 23 Apr 2005 16:40:49 +0200

Congrat's!

So glad Matthias Becker had the PSU changed on mine before selling it!

Stu Ervin · Sun, 24 Apr 2005 16:42:24 +0000

Wow!! You are an inspiration to us all. Good work on getting thru this ordeal!! I am probably going to do the same thing you did, and maybe ( thanks to you !) I wont have to blow up a DAC ......

Can you please tell what MOLEX connectors you found to mate with the CHROMA power connectors ?? So many look a like in the catalogs I am not sure what part numbers to use for this. And, what a bout a cooling fan ??

This could alleve some of the heat build up with an exhause fan to pull hot air out of the box. Some new fans a re very quiet, too.

Jimmy Moyer [21030184] · Sun, 24 Apr 2005 15:18:43 EDT

I got my Molex conectors from Mouser. (Fast, cheap shipping, no min order. Lots of data sheets online. http://mouser.com) Their stock numbers are listed.

For connection to the Power-One MAP-80 power supply Don used tiny spade lugs. These supplies also have the facility for (yet more) Molex connectors. The upside of the spade lugs is that you can make mutiple connections easily, as for the grounds. The down side is if the supply ever needs to come out you'll need to go through the process of making sure everything is properly connected all over. I elected to use the Molex connectors and a couple of wire nuts for multiple connections.

For power supply connection to the Chroma:

  • (3) 6 Circuit Plugs, Molex .093" Pin and Socket Series 538-03-09-2062
  • 3 Circuit Plug, Molex .093" Pin and Socket Series 538-03-09-2032

The pins for these are Crimp Pin Bulk 14-20 gage Molex .093" Pin and Socket Series 538-02-09-2103 For power supply input and output:

  • 5 Position Housing with Locking Ramp, Molex .156 K.K. Connector Series 538-09-50-3051
  • 14 Position Housing with Locking Ramp, Molex 156 K.K. Connector Series 538-09-50-8143

The pins for these are Terminal 18-20 gage bulk Molex .156 K.K. Connector Series 538-08-52-0113

For power supply Power Fail signal:

  • 2 Position Housing with Locking Ramp and Ribs, Molex .100 K.K. Connector Series 538-22-01-3027

These pins are Crimp Terminal, Tin, 22-30 gage, Molex .100 K.K. Connector Series 538-08-52-0123

Re: Heat and fans. Many years ago when stories about Chromas and heat started going around I attached a heat sink to the back panel of mine. I sanded off all the paint from the clear area, cut a heat sink from an old stereo to fit and bolted it on with heat sink grease. With the original supply, this got hot enough that it was uncomfortable to touch which tells me it was working. I did experiment with external boxer fans, but though these cooled the heat sink, all were audible. Given I now have a silent power supply, I hope I can get by without a fan. The frame of the Power One supply is its heat sink. I'm hopeful that a thermal connection to the back panel (and my heat sink) will be a final solution.

Stu Ervin · Tue, 26 Apr 2005 19:32:20 +0000

Jim has really done his homework on these connectors. I think this is valuable information to anyone with a power supply problem. Is there somewhere on the website to archive these molex part numbers?

Thanks Jim!!!

Chris Ryan [21030691] · Tue, 26 Apr 2005 21:53:52 -0700

The message will be included in the list archives. But perhaps there is some value in putting together a page with this sort of repair information. Or it could be included as an addendum to Martin Straw's Diagnosis & Repair article. Any other ideas?

Fwd: Chroma oscillator boards

From: "John Setej"
Date: April 24, 2005 6:33:32 PM PDT
Subject: Chroma oscillator boards

I am a former chroma owner interested ner and have a couple of spare parts that I would like to sell. If you have anyone interested, I have a couple of boards that I would like to sell for $150.00 each US Dollars.

If anyone is interested they can email me at: johnsetej@hotmail.com

Knockin & EQ

Vincent Russo [21030433] · Wed, 27 Apr 2005 14:17:11 -0400

Hallo All,

Our Chroma knocker when moving the parameter slider is developing a mind of its own and pounding out some bad rythms : ) Is this a easy fix and part to replace/find ?

Has anyone ever disconnected the Chroma EQ to see if this might lower the noise floor slightly?

Ron Joseph [21030042+] · Wed, 27 Apr 2005 19:33:11 +0000

I disconnected the knocker altogether.Its placement was creating a clacking sound when the keys below it were struck.More than likely the aligment of the rail inside got moved slightly as I'm getting stuck notes in the lower half of the registry requiring me to open her up and rebend the metal contacts.Anybody else have this problem?

Stu Ervin · Wed, 27 Apr 2005 21:47:58 +0000

you know it could be that the knocker is OK, its only trying to follow bad directions from the parameter slider. could be dirty in the slider pot (try some contact cleaner spray) ; or a solder joint on the slider is breaking down and becoming intermittent.... Dont think the knocker is smart enough to make up its own rythms....

Vincent Russo [21030433] · Wed, 27 Apr 2005 18:17:20 -0400

That could very well be it. My slider it bent and slight off kilter. It's gotten a few sprays of Caig Calilube and is much smoother since coming out of storage. The knocker noises and edit parameter glitches go away after about 20 minutes of warmup now.

Is replacing the the edit slider a easy job ? Does anyone have the part I would need that I could buy affordably?

THX

David Clarke [21030085++] · Wed, 27 Apr 2005 18:14:32 -0400

you know it could be that the knocker is OK, its only trying to follow bad directions from the parameter slider. could be dirty in the slider pot (try some contact cleaner spray) ;

While it is always possible that the tapper itself could be ill - I tend to agree that the more common source of tapper problems often lie elsewhere.

Following on to the note above, a good item to check is whether or not the decimal point ("program modified" bit) in the display indicates that a change has occurred. If it does, then the Chroma does think that something in the patch changed (and so it dutifully tapped the panel for you). If you can find out (and fix) the reason for the unexpectedly changing value (e.g., a panel button getting weak and asserting itself - or the slider issues noted above), then the tapper craziness should also go away.

If you don't see a panel change, but the tapper is still tapping (esp. if the set-split command to turn the tapper off doesn't help) then you might want to take a peek at the electronics controlling the operation (ref: Service Manual p #6-5, the i/o board schematic). The tapper is controlled through a 74LS74 flip flop, a cap or two and a transistor. I've also seen cases where the transistor (and/or some of those other components) have gotten sick - causing funny tapper behaviour.

Has anyone ever disconnected the Chroma EQ to see if this might lower the noise floor slightly?

For me, the outputs are quite quiet; however, a quick check to see if the EQ might be adding noise would be to use one of the mono outputs in the "audio inputs/outputs" section on the back panel (as opposed to the main mono out).

If you hear extra noise when using the main mono out but don't hear it when hooked up to the other outputs - then it may be the EQ (since the EQ only affects the main mono and balanced outs - not the invidual in/out 0/1/2/3 ports).

If you hear noise on all the ports, then it would be matter of tracing back to see where the circuit its coming from. One quick test would be to disconnect the audio inputs to the EQ board. If the noise goes away, then the noise source is somewhere back towards the voice cards. If the noise remains (without any audio input), then perhaps there's something going on with the op-amps/CEM3360 on the volume/EQ board.

Vincent Russo [21030433] · Wed, 27 Apr 2005 18:38:51 -0400

Thank you for there tips Dave, even if you went beyond our technical knowledge a bit : )

Does the fact that the problem goes away after about 20 minute warmup give you any clues. And also worth noting the data readout does have ghosting where the value is changing while the knocker is batting out beats : )

and yes the edit dot does come on when all this is happening.

Jimmy Moyer [21030184] · Thu, 28 Apr 2005 14:21:12 EDT

This happened to me years ago. That the display is jittering means the AD converter thinks the value it's seeing is changing. Check the two screws on top of the big capacitor in the power supply. If they're not tight the outputs will not be totally stable. The AD converter's reference voltage seems to be the most sensitive part of the Chroma to this. When the power supply heats up the metal expands and the connection gets better. The screws will gradually get looser.

While you're at it, verify the terminals on the little circuit board on top of the capacitor are mounted underneath it, as the service manual recommends.

Be aware that there can be a charge on those terminals even after the Chroma is off. If you don't know how to measure or discharge the cap, best to wait a while after the Chroma is off.

Chroma secret weapon

Vincent Russo [21030433] · Wed, 27 Apr 2005 18:20:13 -0400

It may be the biggest over expense for what it does in our studio, but the Chroma sure sounds fantastic through a Roland Dimension 3D Spatial Enhancer/Chorus. What it does it does well and the Chroma seems like a great source for it! (Chroma XLR out to DD XRR in)