Skip Navigation.
Section 0

ChromaTalk Archives: December 2000

Midi Converter & pedals?

Paul Hackett-Evans [21010094] · Sat, 2 Dec 2000 11:17:58 -0000

HEEEELLLLPPP!!!!, please, Chroma friends!

Well, thanks to a useful tip-off and some detective work by me, I have found Roy Paynter, the UK's only certified Chroma service engineer. Although I've spoken to him about helping to repair my Chroma, I haven't yet asked him if he would like me to list his contact details on the Chroma website. So if anyone in the UK needs to get their Chroma repaired by the best there is, please let me know and I'll contact Roy for you. If Roy says it's ok, I'll ask Chris Ryan if he can add Roy's details to the service listings on the website.

Now, here's the problem.I'm going to retrieve my poorly Chroma today and it's in a sorry state by all accounts. The wooden parts of the Chroma have the famous flightcase foam-rot, the PSU's died, at least 2 voice boards were unable to be autotuned (before the PSU died). Roy can probably fix the electronics (subject to him diagnosing the exact faults, anyway), but all of the pedals (volume, patch change, and the dual sustain pedal unit) are missing, as is the Midiconverter (It was the good one, so I'm a bit upset about that). Otherwise physically it's intact, it just needs some care and attention, plus the missing pedals & MIDI box.

Here's the Help bit - Does anyone know where I can get hold of a new (good) Midi converter and pedals for the Chroma? Even used ones would be ok as long as they work?

Also, what's the best treatment for foam-rot? (Why did Anvil make a case with such a poor choice of materials? Crazy! You'd expect that the instrument would be safe and protected from harm in its own flightcase, wouldn't you!)

I still haven't heard anything from the person who was making switching PSU boards, please can you get in touch, too?

All help will be gratefully appreciated, I love my Chroma and I'd really love to get it back to perfect order again.

Thanks
Paul

Chris Ryan [21030691], Sun, 3 Dec 2000 14:39:38 -0800

Also, what's the best treatment for foam-rot?

I tried "Goo Gone," which seemed to work all right, although it was going to be a lot of work; but it was so potent I didn't feel I could finish the job without poisoning myself. I had CAE Sound (contact details are on the Service page at the site) refinish my Chroma; I'm not sure what they used to remove the foam from the wood, but they told me they used something called "tongue oil" for the finish.

(Why did Anvil make a case with such a poor choice of materials? Crazy! You'd expect that the instrument would be safe and protected from harm in its own flightcase, wouldn't you!)

Apparently all such foam eventually deteriorates. I bought my Chroma seventeen years ago yesterday, and I'm sure no one was planning ahead that far--or maybe they just weren't aware of the long-term problems with the material. I re-lined my Chroma case myself; I had the choice of several grades of foam, but didn't go for the high-end stuff because it was just too expensive (and I don't plan on storing my Chroma in its case again for any length of time).

Dave Bradley [16330135] · Mon, 4 Dec 2000 09:30:34 -0600

Paul sez:

Does anyone know where I can get hold of a new (good) Midi converter and pedals for the Chroma? Even used ones would be ok as long as they work?

I can't help you with the converter, but I'll suggest a bit of heresy on the pedals - don't try to find the originals! My original Chroma CV pedals (made by DeArmond, I think) are both scratchy, jumpy, and don't travel smoothly. I'd replace them with Roland EV-5 pedals, which have a very nice smooth action. The dual piano style footswitch can be replaced with a pair of the equivalent Roland (or other mfg) pedals; you'll need only to replace the two mono cables with the single cable/stereo jack that the Chroma used. The little sequence footswitch square thingie can also be replaced with a similair one from any manufacturer.

Chris sez:

I tried "Goo Gone," which seemed to work all right, although it was going to be a lot of work; but it was so potent I didn't feel I could finish the job without poisoning myself. I had CAE Sound (contact details are on the Service page at the site) refinish my Chroma; I'm not sure what they used to remove the foam from the wood, but they told me they used something called "tongue oil" for the finish.

That's "tung oil", actually. Provides a lovely finish, but I've never been able to work with it and get all the bubbles out. I use MinWax Wipe-On Poly, a great polyurethane finish that even a klutz like me can use to create a lovely finish. Just remove the old finish and welded on foam with steel wool first.

Don Tillman, Mon, 4 Dec 2000 22:40:00 -0800 (PST)

I can't help you with the converter, but I'll suggest a bit of heresy on the pedals - don't try to find the originals! My original Chroma CV pedals (made by DeArmond, I think) are both scratchy, jumpy, and don't travel smoothly. I'd replace them with Roland EV-5 pedals, which have a very nice smooth action.

My choice would be different...

The original DeArmond pedal is very nice and built like a tank. If one is scratchy, jumpy or rough it probably just needs some cleaning and lubrication. Worst case, it's a simple matter to replace the pot.

I think Roland pedals are cheesy; cheap plastic housing and a cheap pot. I've witnessed one die within the first hour of use.

For the sustain and sustanuto pedals I highly recommend the Korg DS-1 pedals. Very nice feel, much better than the originals. And yes, you need to wire up two Korg pedals on a common cable.

You can see my pedal setup here: http://www.till.com/articles/chroma-pedalboard.html

That's "tung oil", actually. Provides a lovely finish, but I've never been able to work with it and get all the bubbles out.

I refinished my Chroma several coats of semi-gloss Verathane Diamond Finish. This stuff looks great, is really tough, and is water soluable for easy cleanup. I've been very happy with the results.

-- Don

Thanks & good news

Paul Hackett-Evans [21010094] · Mon, 4 Dec 2000 23:04:26 -0000

Thanks Chris & Dave,
You've both been really helpful and I'll follow your advice.

My friend Pete's chasing up his contacts at the College to see whether he can rescue their Chroma. I'll let you know what he finds.

I think that in the UK, the Chroma was launched around the same time as the DX7 and this is why it was neglected. Lots of Brits caught onto the marketing hype of the time, "if it ain't digital, it ain't any good". But if you tried playing a Chroma, well.....you know what I mean.

Most musicians have an instrument that's theirs, that they feel good about, and that's the Chroma for me. Pete and I used them a lot at music school and afterwards. I stopped playing when I injured my right wrist badly. Although I sold the Korg, Roland and Yamaha keyboards I had, I wouldn't part with the Chroma. I loaned it to Pete until I felt ready and able to start playing again. Meanwhile a wife & kids came along and ten years just raced by. Now I want to learn to play again so here we go. Lots of hard work coming, but it'll be worth it.

OK, now for the REALLY good news:

I emailed Ken Ypparila [21030229] about the MIDI converter and he replied today. Here is his reply:

Paul,
I am currently working on making some more MIDI interfaces. I will let you know when they are done.
Ken

I can't tell you how delighted I was to get that! I've already replied to Ken that I definitely would like to have one when they're ready. By the time he's got them ready, my Chroma should be 100% again, too.

The Syntech/Chroma Cult/KMX MIDI retrofit is still available.

Thanks guys, you're great!
Best regards
Paul

Don Tillman, Sat, 9 Dec 2000 09:46:32 -0800 (PST)

I think that in the UK, the Chroma was launched around the same time as the DX7 and this is why it was neglected. Lots of Brits caught onto the marketing hype of the time, "if it ain't digital, it ain't any good". But if you tried playing a Chroma, well.....you know what I mean.

There's more to it than that... The Chroma came out in '82 and the DX7 came out in '84 (I think). The DX7 was listed at roughly half the price of the Chroma, had a brand new science for making all these new sounds that hadn't been heard before, and had much better specs (96 digital oscillators vs. 16 analog VCOs).

I wouldn't say it was a case of "if it ain't digital, it ain't any good" because the DX7 was the only affordable digital machine at the time. There's an important reason; it was technologically very expensive to do real time digital multiplies in 1984 (hundreds of dollars in raw parts cost) and digital filters require lots of real time multiplies. The cool thing about the DX7 is that FM synthesis can be implemented cheaply in 1983 technology without any real time multiplies. Very clever stuff.

So it's more a case of "hey, there's this new digital way to make interesting noises". Which really is a positive thing.

Not that I'd choose a DX7 over a Chroma.

Chris Ryan [21030691], Sat, 9 Dec 2000 10:08:02 -0800

There's more to it than that... The Chroma came out in '82 and the DX7 came out in '84 (I think).

I'm pretty sure the DX7 was available in the fall of '83 (around the time I bought my Chroma). I briefly considered it (either buying it or waiting until it became available) instead of the Chroma. I took a quick look at some back issues of Keyboard and found an ad for the DX7 in the August 1983 issue. It has a picture of the keyboard and says only, "FM Digital. Programmable. $1395. The performance is about to begin."

Sonics magazine review

Chris Ryan [21030691], Thu, 7 Dec 2000 07:36:58 -0800

I have posted a review of the Chroma from the June 1983 issue of the Australian magazine Sonics.

I received a photocopy of the article when I bought my Chroma. I made numerous attempts over the last couple of years to track down the magazine for permission to post the review; as far as I can determine, Sonics no longer exists, and there is no trace of what happened to it or who might currently own rights. If anyone has any information, please let me know.

ChromaServer - Windows server object library

Mark R. David [21030170+] · Fri, 15 Dec 2000 23:42:33 -0500

For any interested, I've reached the next milestone in my Windows/Chroma interface project. A server for the project is now available, working and documented at [obsolete URL removed].

This server is relatively low level, and follows the architecture of the Chroma programming interface pretty closely, with classes like Program, Parameter and Instrument. One innovation, though not yet fully fleshed out, is a Performance class with support for recording and playback of Chroma performance (Attack, Release, Pedal1, etc.) data. My next step is another server component which will sit on top of this one, exposing classes like Filter, Oscillator and Amplifier. Then on to the client application.

Comments (especially bugs) solicited.

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

Restoration in progress

Paul Hackett-Evans [21010094] · Mon, 18 Dec 2000 01:59:47 -0000

Hi again,

I thought I'd update you on the status of my Chroma as of today, after I have had so much support from you, via the website, the mailing list and directly by personal emails.

My Chroma is 21010094. It was one of 15 Chromas delivered by the importers to the North-East of England in 1983. I personally got to know of the Rhodes Chroma by using another of those 15. That one was bought by the Newcastle-Upon-Tyne School Of Music, where I was a student from 1983-87. (That particular instrument is now rumoured to have been scrapped by the College and given to it's electronics students as a strip-down project. My friend is trying to trace and rescue it now).

21010094 was sold by Rock City Music in Newcastle to a musician in a local band, who used it for 18 months and then traded it in, back to Rock City, for a Yamaha DX synth. Partly because the sounds he had in the Chroma weren't very good, partly because nobody at Rock City really knew how to use a Chroma, and partly because it just wasn't a very fashionable keyboard at the time, it remained unsold and undemonstrated for nearly a year. It wasn't even plugged in or switched on, merely being used to put other, more modern keyboards on!

At this time, I was setting up an 8-track/MIDI studio, for my own band to use and to record demos for local bands. My songwriting partner, Peter Riani and I had been very keen on the College's Chroma, and when Pete told me that he had seen a Chroma for sale in Rock City, I went and tried it out. I bought it for GBP £1000 in 1985 and ordered a Chroma Cult Midiconverter.

I programmed some really good sounds into it, the ones I was most proud of were a stereo recreation of the choir sound from the closing theme of the movie "Starman", a lovely flanged guitar sound, a cor anglais and some rich pads, but there were many more and it was a lovely keyboard. I found it had a character and versatility of its own, which made it a joy to play. It was used on recordings by a number of bands, and well loved.

Our studio overlooked the beach in South Shields, which made it a relaxing and inspiring place to work, as you could write, play and record whilst looking out across the sea. But it did have a downside - in 1987, our premises suffered storm damage and the Chroma needed a repair. This was done by Roy Paynter, whom the UK Chroma importers informed us was the only certified Chroma engineer in Britain. He did a great job and the Chroma continued its good career in the studio.

In 1989, I suffered a bad wrist injury and wound up being unable to play for a long time. I was also setting up home with my wife. I sold my interest in the studio and all of my keyboards except one. I loved the Chroma so much that I gave it to Pete on condition that he should never part with it, until the day that I might start playing again and want it back.

He's had it for ten years, during which time he's written, recorded, rehearsed, programmed and gigged with it. It had a full and busy life, making lots of music and acting as his primary MIDI keyboard. So far so good, that's why I left it with him. About 5 years ago, the power supply developed a fault. Pete asked an acquaintance, who "knew something about electronics" to attempt a repair. The Croma worked again for a while but a year later, it fell victim to a mains electricity power surge from a substation very close to my friend's house. It died there and then. Pete couldn't afford to get it looked at by a proper engineer, so he locked it up in its flightcase, where it remained until I went to rescue it at the start of December 2000.

I now live 150 miles away from Pete and got the Chroma back about three weeks ago. Oh dear, Pete and I found it was covered in thick black gunge where the flightcase foam had reacted with the varnish. The black paint on the metal top panel is scratched and the keys were filthy too. The instrument was completely dead electronically. The Midiconverter was missing, as were all the pedals, footswitches amd manuals. So it's now a restoration project.

I've bought the manuals from a gent on eBay, and I'm sourcing replacement pedals from Korg & Roland thanks to a few of you suggesting suitable alternatives to the originals. (I still want originals if anyone hears of them becoming available).

I've now COMPLETELY disassembled my Chroma. The power supply, which seems to have been badly repaired by Pete's friend, is now in the hands of Roy Paynter, who hopes to put it right and return it to me by Christmas. I've cleaned up all of the other circuit boards and contacts. The voice boards are in anti-static bags in a cupboard. The main panel and its boards are safely stored. A ribbon connector between the I/O board and the Computer board was damaged, I've repaired that under Roy's guidance, though I won't know if it's fully functional until the power supply's back and the Chroma's rebuilt.

I've removed all of the keys, cleaned them up and replaced all the felt as it was ageing a bit. They look great now. I've removed all of the wooden panels and trim for restoration, too. I found that mineral spirits was most effective in removing the black foam-rot (thanks to Ken Y for suggesting it), but the rot had damaged the varnish, so a complete refinish is now in order.

Tonight, I've stripped off all the varnish using Nitro-Mors and white spirit, and this week, I'll be filling the dings in the woodwork (suffered while gigging) then sanding it all smooth. At that point, I'll have the power supply back from Roy, so I'll test the Chroma, to be sure its electronics won't need any more attention from him. We don't want to fully varnish and reassemble it, only to have to break it down again for further repair work.

If all's then well, I'll take the woodwork back off it and start varnishing the panels until they're deep and glowing again. I expect that will take some time to get it really nice. I'll also get the top panel resprayed. Then I'll reassemble the Chroma as a restored working instrument. The final stage will be a new Midiconverter once Ken Y has built his next batch.

I've learned a lot by doing all this. I've documented and photographed every stage of the disassembly and repair to-date, so I can reassemble it correctly. I may scan the pictures onto the web to help anyone else who has to do as I am doing. The Chroma talk guys have been very helpful so far. Thanks! I hope this lets you know how I'm getting on.

Chris, if you'd like to edit this down to post it on the instrument history page of the site, I'd be grateful. Thanks guys and Merry Christmas!

Paul

recommendations

Jason Anderson · Mon, 18 Dec 2000 02:43:49 -0500

Hi Everyone,

I recently purchased a Chroma Polaris, after seeing a buddy of mine play his I just had to have one. I found one on eBay, but it was DOA, no power, nuttin. The previous owner said it was sitting in a closet for 10 years or so. Supposedly it's one of the first few ever built, the serial number is written in yellow, on the bottom of the keyboard # 0001J , and there is no plate attached on the side (like my buddies Chroma Polaris).

After doing some research on the Polaris, I know that there were alot of problems with the first 100 or so, produced. I would love to get mine back in working order. It could be something as simple as the Power Supply. Maybe I can fix this. Can anyone recommend someone who services the Chroma Polaris? Also, does anyone know how I can validate the # 0001J serial number? Is there another place inside with the number?

Thank you for your time,
Jason Anderson

David Clarke [21030085++] · Mon, 18 Dec 2000 19:08:04 -0500

I recently purchased a Chroma Polaris, ... Can anyone recommend someone who services the Chroma Polaris?

The service manual for the Polaris [see Polaris Resources] is quite good, and almost all parts inside are socketed - so it is quite easy to work on. Any reasonable tech should be able to handle the Polaris (Fender still sells the service manual - or at least they used to [see Manuals for Fender contact information circa 1999]).

Also, does anyone know how I can validate the # 0001J serial number? Is there another place inside with the number?

On later Polaris' there was another serial number tag inside the case, just in front of the voltage selector switch. If this is an early model, then that tag might not be there - but if it is, it would be to the left of the battery compartment and ahead of the main line fuse/voltage selector (and behind the end cheek with the two levers).

It is also possible that the S/N is written underneath the keybed as well - but I'm not sure of that one.