Skip Navigation.
Section 0

ChromaTalk Archives: July 2013

Re: EQ board output issue follow-up

Go to first message in thread, June 2013

Matt V [21030757] · Tue, 2 Jul 2013 12:47:59 -0500

Hi all,

Still hoping someone out there might be willing to take on the task of troubleshooting this EQ board. It's far easier for me to send it off than try and haphazardly troubleshoot myself!

thanks!

Matt

Re: registration + problem

Go to first message in thread, June 2013

Sam Shepherd [21010117] · Fri, 12 Jul 2013 01:48:22 +0100

Hi David, Thanks so much for your tips & sorry its taken me a while to get round to looking into it.

THe PSU is indeed Luca's & all the voltages are stable.

now Im just getting Err 27, but if i swap the voice cards around, i still get err 27.. So im guessing its something between the PSU & the connectors to boards 2 & 7...!

anyone else had similar problems?

Appreciate all the help!

Thanks

Sam

Paul DeRocco [21030230] · Thu, 11 Jul 2013 20:54:15 -0700

It could also be a couple of separate faults in the CMOS logic on the channel motherboard.

swedish chroma FS on facebook

Jesper Ödemark [21010135] · Sat, 20 Jul 2013 16:43:20 +0200

Hi list,

one of the elusive 1202's are up for sale (at least I assume he don't have two Chromas these days). So it's most probably 21020003 and the seller is the same Ola who have had it since 2005: [Facebook thread; picture]

I've asked about upgrades etc. Asking price is 25000 SEK (circa 2900 euros)...

Chris Ryan [21030691] · Sat, 20 Jul 2013 21:20:49 -0700

Thanks, Jesper. Do you mean model 2102? If so, how can you tell? The mention of '1202' makes no sense translated from Swedish to English by Google Translate.

Jesper Ödemark [21010135] · Sun, 21 Jul 2013 09:07:35 +0200

Yes, 2102... I have to blame the splitting headache I had yesterday. :-/ This one it is: 21020003 I know the seller since he bought my PS-3200 years ago...

Rodes Chroma

Mirko Lüthge [21010245+] · Sun, 21 Jul 2013 18:53:08 +0200

I am still missing the possibility for external saving/loading of sounds. SysEx ok., but I don't like to use a laptop on sessions.

I am still planning an Advanced Synthex similar to RC (new PSU, new CPU, new keyboard with poly-AT aso) and with a break-out-box (display, keypad and memorycard).

Any idea for the RC/RCE ?

0027 is now mine

Michael McInnis [21030027] · Thu, 25 Jul 2013 22:52:12 -0400

I just brought 0027 home.

27 is presently not making any sound whatsoever and the program memory is wiped. I will have to find time to troubleshoot and bring this beauty back to life

I believe this is new to the registry.

More later.

21030027

Michael McInnis [21030027] · Fri, 26 Jul 2013 02:28:15 -0400

0027 update

Changed the AA batteries out, Did some programming and got 6 cards working.

Memory isn't lasting through a power cycle.

There are a number of membrane switches not working in the master section, but all the program/parameter buttons work.

The keyboard is all good and the levers too.

All the boards are marked Arp. I think they all have inspection stickers marked 3-17-82.

Word is that this was owned by producer Anthony Resta whom has worked with Duran Duran, Elton John and other top acts. I don't know of any projects the Chroma was specifically used on, though.

I have ordered a replacement power supply and have the CC+ kit ready to install.

So far, I am encouraged that I didn't make a huge mistake after getting to hear some fat sounds out of it.

Regards,

MM

Chris Ryan [21030691] · Thu, 25 Jul 2013 23:40:56 -0700

Re: 0027 update

Congratulations, Michael. Sounds like you got one of the "first fifty." There have been a few others reported without model numbers [this unit was added to the Model 2103 page, though, because of its inclusion on the foil label].

I'll add it to the registry. If you are so inclined, could you let us know the price for the price history?

Michael McInnis [21030027] · Fri, 26 Jul 2013 02:47:33 -0400

Re: 0027 update

$1800.00 US as is/no return.

In the store the synth showed an error on all eight cards.

Michael McInnis [21030027] · Fri, 26 Jul 2013 02:53:54 -0400

Re: 0027 update

Also, I should mention all that came with it was a dual pedal...nothing else but the AC cord.

Paul DeRocco [21030230] · Fri, 26 Jul 2013 00:19:11 -0700

Re: 0027 update

From: Michael McInnis

Memory isn't lasting through a power cycle.

If fresh batteries don't keep the memory alive, the most likely culprit is CR1, the germanium diode. If the battery supply ever got shorted out momentarily, it would pop that diode in a few microseconds. Fortunately, they're cheap.

There are a number of membrane switches not working in the master section, but all the program/parameter buttons work.

Did you try opening the connectors and reseating the tails? As I recall, sometimes those old Molex ZIF connectors would crack and break, and so not grip the tail properly. If that turns out to be your problem, and not the membrane switches themselves, I have some new-old stock of those connectors, in either black or turquoise. (Sorry, I'm out of the mauve or the Tartan plaid.) I also have some of the Polaris-style Trio-Mate connectors which aren't ZIF but are probably more reliable long-term.

$1800.00 US as is/no return.

In the store the synth showed an error on all eight cards.

You're lucky I didn't get there first! I'd love to have a really early one.

Also, I should mention all that came with it was a dual pedal...nothing else but the AC cord.

That's the most important accessory. If you want a pedal, you can use any ARP pedal, or the Chroma Polaris pedal, if you happen to come across one. You could also probably retrofit a Roland or Yamaha pedal, by replacing the pot and rewiring it. It needs to be a 0 to roughly 100K variable resistance between tip and sleeve. The Sequence Program footswitch is also an ARP standard, although the Chroma will work with pretty much any footswitch.

With the CC+, you won't need a cassette interface cable or a Chroma interface cable.

Michael McInnis [21030027] · Fri, 26 Jul 2013 08:06:36 -0400

Re: 0027 update

As of this morning, after a quick cleaning of the ribbons with a pencil eraser, all switches are now working.

0027 is slowly coming back!

Is there danger if I install the CC+ board before my new power supply gets here?

Thanks!

MM

Heinz Weierhorst [21010276] · Fri, 26 Jul 2013 16:16:46 +0200

Re: 0027 update

Hi Michael. I think it should be better to wait for the new powersupply. The most critical and faulty part on the old supply is the +5V digital rail. This is the main power for the CC+ and other digital parts in the Chroma. So be patient.

Heinz

Al Tutlys [21030645] · Fri, 26 Jul 2013 10:44:35 -0400

Congrats, you will get to that moment when you realize it was worth it to resurrect a piece of history. All the help you will find here is invaluable.

God luck, Al Tutlys

Luca Sasdelli [21010226] · Fri, 26 Jul 2013 16:36:07 +0200

Re: 0027 update

I agree with Heinz,

your SPSU kit will be shipped tomorrow morning.

Cheers
Luca

Michael McInnis [21030027] · Fri, 26 Jul 2013 16:07:46 -0400

Re: 0027 update

Memory is working now. I replaced the batteries that were in the unit in the same orientation as the "originals"...as it turns out they were installed incorrectly.

So, now all I need to resolve is card 3 & 5 failures and replace the tuning fader...which is broken. Is there a source for the knobs? (fadertops?)

Also, my synth has roms labelled 10. Are some of the split key diagnostics missing on this early rom version? Couldn't find that info.

Thanks again!

MM

Paul DeRocco [21030230] · Fri, 26 Jul 2013 18:58:26 -0700

Re: 0027 update

From: Michael McInnis

So, now all I need to resolve is card 3 & 5 failures and replace the tuning fader...which is broken. Is there a source for the knobs? (fadertops?)

Is it just the black knob that's busted or missing, or is the slider bad?

Also, my synth has roms labelled 10. Are some of the split key diagnostics missing on this early rom version? Couldn't find that info.

I think so, but I don't have a record of the early firmware versions. But it won't matter once you get the CC+ in there anyway.

Michael McInnis [21030027] · Fri, 26 Jul 2013 22:13:34 -0400

Re: 0027 update

Stem of the tuning slider is sheared off with the cap missing.

I have been trying to do the voice diagnosis routine, but it doesn't seem to be there.

I think I am done tweaking until the new power supply comes. But, I am happy to gave a mostly working synth now.

Regards,

MM

Paul DeRocco [21030230] · Fri, 26 Jul 2013 20:49:52 -0700

Re: 0027 update

From: Michael McInnis

Stem of the tuning slider is sheared off with the cap missing.

How'd that happen? It's a metal pot. Or did the complete stem get yanked out of the body?

Assuming it's the same as the ones I've got in mine, I have extras. Contact me off-list.

Michael McInnis [21030027] · Sat, 27 Jul 2013 07:36:42 -0400

Re: 0027 update

Not sure how it happened as it came that way to me, but a part of it is level with the panel top.

Michael McInnis [21030027] · DATE

ARP Branded Board in 0027

Here's an interior shot of 0027

20130027ARPboardthumb

Rob Witt · Mon, 29 Jul 2013 13:44:28 -0400

Re: ARP Branded Board in 0027

Recognize that Ciarlone layout anywhere.... ;-)

John Leimseider [21030434++] · Tue, 30 Jul 2013 01:03:51 +0000

ARP Branded Board in 0027

I still have one ARP voice board to sell...

Go to next message in thread, August 2013

Non-standard pitch fader & cap.

Michael McInnis [21030027] · Sat, 27 Jul 2013 15:45:31 -0400

Here are pictures of my pitch fader and the eq caps. These don't match later production.

21030027pitchfader

21030027eqcaps

Does anyone know where I might find a replacement fader? Paul has one of the old caps.

Thanks!

Doug Terrebonne [21030114] · Sat, 27 Jul 2013 13:33:06 -0700

Those appear to be the type of sliders used in the ARP Quadra and Solus so you might try searching for those... I don't have any but I do have a couple of the caps...

Michael McInnis [21030027] · Mon, 29 Jul 2013 09:00:29 -0400

I am having zero success trying to find a replacement slider. I have visited all the vintage parts web dealers I know.

If anyone has a lead, please send it to me.

Has anyone ever transplanted a wiper from one pot to another? I have found pots with the correct wiper stems but the wrong resistance.

Jesper Ödemark [21010135] · Mon, 29 Jul 2013 15:24:38 +0200

That was common practice on ARP 2600 and Odysseys until replacement sliders were made to special order. So, I'd try that if I were you.

Technician Larry [21030198] · Mon, 29 Jul 2013 07:44:23 -0700

YES! You can take 2 sliders of the same make but different resistance values apart and co-mingle the parts. I’ve done that many times.

Paul DeRocco [21030230] · Mon, 29 Jul 2013 17:14:01 -0700

The tuning slider is just a voltage divider across the +5V analog supply. It doesn't matter if it's 1K, 10K or 100K, as long as it's linear taper. If you can buy a 100K, you're all set.

Michael McInnis [21030027] · Mon, 29 Jul 2013 22:28:54 -0400

Great! Thanks for the info.

Trying to reach Sandro Sfregola

Tobias Menguser [21010303] · Mon, 29 Jul 2013 21:05:18 +0200

Hi all,

I received my new Chroma 2 months ago and would like to update the synth with the CC+ CPU board and the Midi interconnection kit.

For this reason I sent several emails to Sandro [21010294] to [email address removed], but unfortunately didn't receive any reply.

Did anybody talk ti him during the recent weeks?

Sandro, where are you?

Luca Sasdelli [21010226] · Tue, 30 Jul 2013 12:25:48 +0200

Hi,

you should write to David Clarke (pls check [the CPU Plus page] for the mail address) to order a CC+: David will update you about board availability.

Tobias Menguser [21010303] · Tue, 30 Jul 2013 13:12:38 +0200

Hi Luca,

Thanks for your reply.

I just sent a mail to David.

Cheers,

Tobias