The No.1 Website for Pro Audio
 All  This Thread  Reviews  Gear Database  Gear for sale     Latest  Trending
Calrec CL-1508
Old 9th June 2005
  #1
8070
Guest
Calrec CL-1508

Does anyone have any info on this compressor module...i have one and i really want to rack it up...having a hard time finding any info...and Calrec won't return my emails...
Attached Thumbnails
Calrec CL-1508-fb_1_b.jpg  
Old 9th June 2005
  #2
Lives for gear
 
gainreduction's Avatar
 

I'm not totally sure about that particular module 'coz the Calrec desks I've come across (the early 80's, partly handbuilt ones) have different compressormodules. Yours looks older to me. However, it should only be a matter of a couple of things.

1. You need to find out what current it needs to power up properly. Send some e-mails to service-techs, dealers and "vintage-modification-makers" and I'm sure you'll get an answer somewhere. To find the schematic is of course the best thing.

2. You need to figure out the pin-out of the multiconnector (which you might have a hard time finding a matching connector for. You might need to replace it). Again, schematic..

3. Important ! Check the following: some Calrec desks have all I/O-transformers mounted in a separate transformer-section located under the mastersection. That might mean that your module needs input- and output-transformers but you don't have them, they're still in the frame... In that case you need to get transformers. I think Calrec used Lundahl transformers. Those are easily available.

I don't know where on the planet you're located but here are two companies in Germany that racks up a lot of vintage stuff:

www.hestudiotechnik.de
www.vintagecity.de

Drop them a mail and see if they can help. Good luck !
Old 9th June 2005
  #3
Here for the gear
 

These look similar, but not identical, to DL-1656 modules. I have a pair of those, and really like them a lot. However, I think that yours is older, based on both the name/number, and also the logo, which is the old Calrec logo, before AMS bought them up in the 80s for a while. I'm not sure if the compressor module pinouts and/or supply voltages changed between CL and DL console series... otherwise I'd just send you my docs.

Try calling or emailing Calrec again. Their technical department were incredibly helpful to me, sent old schematics, pinouts etc, when I was tryng to figure out a couple of old Calrec modules, both of which were long out of production. They may take a while to respond.

FWIW I bought my compressors from Mike Nehra at Vintage King, and I know he has Calrec stuff sometimes, so you could try contacting him - he may have documents around. (And I'm sure he could have one of his guys do the work too, if you wanted to hire them.)

It's hard to tell from your picture - what's the wire? Does this have some kind of wiring harness already? Edge connector? ANY info at all on pinouts?

If you get in contact with Calrec again, make sure you ask for alignment instructions, and what the power supply voltages are meant to be.

Good luck.
Old 9th June 2005
  #4
Lives for gear
 
Wiggy Neve Slut's Avatar
 

Definately get in touch with calrec.

They were incredibly helpful for me also. They mailed hardcopy schematics, circuit diragrams and wiring pinout to me for some modules years ago.... all FREE OF CHARGE to Australia.

Calrec stuff is the bomb and is yet another 'sleeper' that people will actively chase once the dwindling numbers of neve consoles have been snapped up.

Also try the crew @ vintage King as they sell a few of the calrec comps etc and they will prolly have a pinout and some tech docs for you as well.

Hope it works out for you
Wiggy
Old 9th June 2005
  #5
Old 9th June 2005
  #6
Gear Maniac
 
BJohnston's Avatar
 

Desol,
Hey, I believe we've tried emailing eachother about this unit. I bought 1 of these units from the same auction. I finally got in touch with Calrec after a couple of weeks of emailing everyone on there contact list. What they told me was a little surprising. They don't have any records of these units. Apparently when they were bought out the new folks didn't bother cataloging (sp?) the more vintage products. It's pretty rediculous, but it's the truth. I've spoke with Brian Roth who is a tech/custom rack designer. He's going to try and reverse engineer the unit in order to rack it up for me. Brian posts here regularly. You might try getting in touch with him. He might be able to help once he can figure my unit out. Good luck, I feel your pain.

B
Old 9th June 2005
  #7
C/G
Lives for gear
 
C/G's Avatar
 

Vintage King or Dave at Marquette Audio Labs. He racks Calrec as well.
Old 9th June 2005
  #8
Gear Head
 

Brent Averill racks up Calrec stuff too. Might want to contact his company.

Man, that calrec stuff is freakin' great. Enjoy!!!
Old 9th June 2005
  #9
8070
Guest
Thank you so much...all you guys for responding...
I'm really excited to get it taken care of. This is my first rack project
so i need all the help i can find.

Fadeout: Yes, it came with the harness in the pic...don't know if it's right or not though? Or which leads are for what.

Bjohnson: I emailed brian actually..but hasn't gotten back yet. It's funny you mentioned his name..he's seems to be the cat that's going to bat for us here...let me know what happens with your module...k man? If you forget...i'll check back with you in a while. Did your unit come with the wire harness too?

Thanks again for all your replies!
Old 9th June 2005
  #10
Gear Maniac
 
BJohnston's Avatar
 

Yeah mine came with the multipin connector with what look like an input lead and an output lead. It also has what looks to be leads for a power supply. Something interesting though, I found a piece of paper inside the unit itself floating around in there. It looks like whomever soldered the leads onto the mult connector left some sort of clues as to what is what. Not being a tech however i don't know quite what it means. Look inside. See if you have something similar. I'm sending mine to Brian this week. He says he'll get started on it soon. I'll let you know what happens. Good luck.

B
Old 10th June 2005
  #11
8070
Guest
Cool...thanks again man...and good luck with yours.

Old 10th June 2005
  #12
Here for the gear
 

Hi Desol,

I can't tell from the picture if the harness is right or not.

For whatever it's worth - which may be nothing - here's the info on my DL1656. These appear to be the same size module, but like I said, I think they are from a later series of consoles. So they *might* have had a totally different wiring and power supply.

Anyroad (as they say in Calrec land) the DL power supply I have has +15V, -15V, common, for audio and a 9VDC supply for the LEDs. (The schematic for the same unit actually specs 16V and 10V respectively)

The connector on the back of the DL module is 32 pins, wired as follows (numbers left out mean there's no connection):

1: L1 (stereo link 1 )
2: L2
4: remote meter
5: remote meter
7, 8: audio input ground
9: audio input positive
10: audio input negative
15: -15V
16: +15V
17: PSU common
18: 9Vneg (LED power supply)
20: 9Vpos
29: audio output positive
30: audio output negative
32: audio output ground

So, if your harness has connections on those pins, this might help you.

If you take off the side panels of the module (loosen the screws that clip on the side panels and slide them off) you'll see how the rear connector hits the PCB, and maybe you can deduce something from that. The PCB may be labelled if you're lucky. (And maybe that piece of paper that BJohnston mentioned has the answer.)

Good luck with it. Don't blow it up!
Old 12th June 2005
  #13
Lives for gear
 
brianroth's Avatar
 

Sorry guys...I was out of town this week due to a client's "mayday" in D.C., so I'm just trying to get caught back up with everything.

Desol...I don't recall seeing an email from you..I'll PM you with my contact info in case it got lost in my crazy little world.

I'm hoping that the harness that came with Barry's unit is close enough to reality to be a good springboard for reverse engineering, but I'll malke note of the pinouts that Fadeout posted as well.

Bri
Old 18th June 2005
  #14
8070
Guest
Thanks fadeout and brian...!

The pinout that you have fadeout looks to be the same as mine...don't know if the voltage is the same tho...
Old 19th June 2005
  #15
Lives for gear
 
brianroth's Avatar
 

I did some foil tracing today, using Fadeout's pin assignment numbers as a springboard, and it seems to be a match on everything I traced. I didn't dig into the pin 18 & 20 lines since the foil traces go everywhere. I'll work backwards from the LED driver chips and see if it makes sense. The main power rails, and audio in and out appear to match Fadeout's assignments.

I would agree that + and - 15 V or 16 V would be the proper audio rails since the module has a bunch of TL072 chips, which are rated +/- 18VDC absolute max. I'm hoping the Lundahl output transformer has a "step up" ratio in order to provide a higher output swing than what +/- 15V rails would otherwise allow.

Bri
Old 13th July 2005
  #16
8070
Guest
Hey Brian!

Was wondering if you have found out any more about the Calrec module?
Hopefully everything is the same as fadeout's pinout.
You mentioned something about the transformer step up?
The unit has 15v for operation and 9v for led...so that means i need a 24v power supply right(toroidal)? I'm a little confused how to hook up the 9v/15v...

Thanks Brian
Old 14th July 2005
  #17
Lives for gear
 
brianroth's Avatar
 

Desol, no, I haven't. A friend of mine in Seattle *thought* he had some info in his files, but I never heard back from him before he and his family left for vacation a couple weeks ago. I had put everything on standby wating to hear from him.

The voltages question was also what was concerning me, since analog comp/limiters tend to be fussy about those. The thing has internal trimmer pots that often rely upon a "correct" rail in order to operate correctly. IOW, if the factory aligned the module for, say, 18 VDC rails and it later is powered from 15 VDC rails, the alignment will likely be wrong.

As for creating the 9VDC, all you need is a three terminal regulator IC to derive the lower voltage from the 15 (?) rail.

Bri
Old 14th July 2005
  #18
8070
Guest
Cool...i'll have to figure out the regulator IC for the 9v power...would i have to make an additional little circuit board for that and mount it in the case? I'm pretty green...the way i understand it is that i would go from the transformer to the regulator IC...from the leads before the reg to the module...after reg to the led...

It looks like you can put another meter on it too...remote meter pins?....a PPM 14?

Somethings telling me that it's the same as fadeouts pinout...only on mine they haven't got wires on the ground pins for the in's/out's...i'm thinking i should connect those to my TRS grounds...

There's no default position on the trimmer...for 15VDC?
Old 14th July 2005
  #19
Lives for gear
 

Hi Guys
Sorry I can't remember all the parts of this thread but here goes:
The supplies to the desk were Pos and Neg 17.5volts and 8 volts for the 'lamp' supply. Depending on exactly which module there is also 5 volts available which was regulated from the + 8 volt rail supply. I can't remember if the CL you have uses 5 volts. The connector is a standard DIN 41612 64 pin AB connector (2 row)although it might only be the 32 pin variant A 64 pin is only a bit more expensive.
I don't think I have the schematic for this module but in terms of powering there are diodes to prevent the main audio rails from being reversed (in series with the power pins).
If it does not have a Lundahl LL1517 transformer in it then the unit will run internally at probably -10dB (possibly -6dB or other level) and the unbalanced out would feed another card which would have an amplifier with transformer to bring it up to 0dB.
The input is probably balanced using an op amp stage which 'lost' either 6 or 10dB, likewise the sidechain input. The power required is max 200mA for audio and perhaps a touch more for 'lamp' supply. All reference volts used internally are derrived from the audio supply. The lamp supply should come from a separate transformer for best results. The negative of the lamp supply (OL) and OV of the bipolar audio supply need joining, on the back of the module connector if you only have 1 module. If you find reference to BSE it is not the mad cow disease but Back Stop Earth, which is the Calrec term for a clean earth that the mix amp stages were linked to. This eventually joins OV and OL and chassis. All 4 joined at the tech earth bolt on a full desk.
I will now see if I have the schematic. Feel free to PM me for other info.
Matt S
Old 15th July 2005
  #20
Lives for gear
 
brianroth's Avatar
 

Excellent info, Matt! Fadeout had posted the pinouts which look like what's in Barry's (aka BJohnston in this thread) module that I have here in Ye Shoppe, but Fadeout specified 15 V rails, which I thought to be a bit low for pro gear. 17.5V sounds more like it.

This one has the single 32 pin row DIN connector (the other row is "depopluated"), and fortunately Barry also received the female socket with the module.

I indeed noted the polarity protection diodes on the +/- rail inputs...made those pins easy to identify! The module also has the Lundahl LL1517 tranny.

I didn't know these had a side chain path. Another interesting tidbit which was not noted on Fadeout's pinout listing (for, admittedly, a totally different module).

In my current thinking process, I figured a sufficently stout +/- supply could serve both the audio rails as well as the lamp driver rail. My thought was to use a 3-terminal regulator fed from the audio + rail to derive the lower voltage needed by the lamp driver, versus adding a whole separate supply for LEDs. Keep in mind...Barry has only one module.

Any additional info would be greatly appreciated, since Calrec has basically told Barry they "lost" any service info/schematics! That makes it quite a tricky process for me since I need to otherwise totally reverse engineer this module.

I had my fingers crossed that Rick, a friend in Seattle, had info in his files, but he's on vacation in Europe at the moment.

Bri
Old 15th July 2005
  #21
Lives for gear
 
brianroth's Avatar
 

Quote:
Originally Posted by desol
Cool...i'll have to figure out the regulator IC for the 9v power...would i have to make an additional little circuit board for that and mount it in the case? I'm pretty green...the way i understand it is that i would go from the transformer to the regulator IC...from the leads before the reg to the module...after reg to the led...

It looks like you can put another meter on it too...remote meter pins?....a PPM 14?

Somethings telling me that it's the same as fadeouts pinout...only on mine they haven't got wires on the ground pins for the in's/out's...i'm thinking i should connect those to my TRS grounds...

There's no default position on the trimmer...for 15VDC?
It probably would be easiest to use a piece of "perfboard" since the 3-terminal regulator needs a couple of capacitors for bypassing. The regulator might need a heatsink depending upon how much current the LED drivers pull.

The 78xx series is available in many voltages, including 8 and 9 V:

http://www.st.com/stonline/books/pdf/docs/2143.pdf

ST is one of many suppliers of these "generic" regulators...that just happened to be the first data sheet I found via Mouser's website!

My concept is to feed the input of an 7808 or 7809 (whichever works out as the correct voltage) from the audio "+" rail (which Matt has said is actually 17.5V).

I haven't given any thought to the best grounding scheme! I was just happy to get some beginning pinout info from Fadeout earlier. Geeez..a full schematic would be SO nice so I don't have to spend a bunch of time (and some of Barry's money...just kidding Barry, I say with a big grin) tracing out a bunch of circuit board foils.

Desol, I didn't understand your last line re. "default position of the trimmer".

Bri
Old 15th July 2005
  #22
Lives for gear
 

Hi Brian and co.
I think I am wrong about a sidechain input. Looking at a pic that has been sent there is only 1 pair of input caps (C1 and 2) which are audio input.
I expect for 1 module you can run a 7808 or 9 to power the leds. Make the common earth connection at the connector socket. The 8 volt supply has nasty current 'bumps' due to it powering the bargraph leds so use a decent reservoir cap (1000 uF or so) after the regulator.
I have a couple of spares of the potted blue circuit blocks. I can't remember what is in them but they never failed.
The output is fully floating from the transformer so use a screen if you want to. The input is balanced as well but a typical op amp configuration but with HF and LF trims.
Power should be 17.5 volts and I would suggest a 1 amp 15+15 from Power One
and adjust it up to 17 if it will go that far. Use a LM7808/9 as mentioned for the 8L supply. Use a 'data sheet' to show what components you need around the chip which will want a heatsink (isolated from ground to prevent earth loops). There is a meter output but I suggest you get the thing working and measure what you get coming out and scale a meter for it. On a module I have a diagram for, it was 2V Dc =10dB. I was involved in testing desks of this era but these modules were relatively 'stand alone' so assuming they worked from the module test department I didn't play with them. The factory diagrams would have been transferred to AMS during that merger and probably abandonned when Calrec demerged as by this time this series of desk would be 6 or more years old and all complete desks had full manuals. Many of the desks have been sold off by accountants of corporations who don't care about audio so the manuals could be anywhere.
Matt S
Old 15th July 2005
  #23
Lives for gear
 
brianroth's Avatar
 

Once again, Matt, your information is MOST appreciated and helpful.

I told Barry that I'd give my "best shot" when getting his module running, yet I was handicapped without factory docs.

Hence, I could spend a lot of time reverse engineering the pin outs, etc, and since I do this for a living, I need to apply some billable time to the project. (ie, Barry's project billing)

Matt...can we "bribe you" for **your** time...scour your files for any useful info...scan it for me...and I'll pay for your efforts, and then I'll spread the costs between Barry and Desol?

Barry is a client/friend and Desol is a correspondent with a similar problem...ie, getting a module workable.

I'm not tying to make a "killing" here...just getting enough info to get Barry's module workable, and then share info with Desol.

Thanks!!

Bri
Old 15th July 2005
  #24
Here for the gear
 

Quote:
Originally Posted by brianroth
I didn't know these had a side chain path. Another interesting tidbit which was not noted on Fadeout's pinout listing (for, admittedly, a totally different module).
Hey Brian et al - on my units, the first 2 pins (L1 and L2) are basically sidechain inputs, as I recall... I only used for stereo linking the two compressors, but I seem to recall the schematic showing those pins as the sidechain input. (Again YMMV on your modules.)

best,
Chris
Old 15th July 2005
  #25
Lives for gear
 

Hi there
If they are marked L1 and L2 then they are link in/out pins which connect the processed sidechain signal to the next module. They are not audio signal inputs as such but a version of the fluctuating DC that goes into the VCA chip (after scaling).
Matt
Old 15th July 2005
  #26
damn, I nearly bought that one. The guy offered 4 of those the first time, and I couldn't get back home to place a bid.

How are they?
Hope you can get them connected.
Old 6th August 2005
  #27
8070
Guest
Hey Brian! How's things?

Just checking in to see how the other module is coming?
I want to rack mine soon...but i need some help with getting the power going...
I have some majorly basic questions:

1. Does the power supply/transformer have to be putting out 17.5 volts AC or DC?
My understanding is that i just go from 110v through an AC to DC transformer
that steps things down to 15 or 17.5 VDC...?

2. As Matt suggested the power should be 15x15 1 amp. Does this mean that
there are two pairs of wires coming off the supply 15 volts each? 1 for main
and 1 for led? How do i adjust the power up to my 17.5 volts? I am thinking of
building the regulator circuit for the led...but i may get someone to do it for me...

3. I want to put the unit in a 1u rack sideways...do you have a link for any power
supplies/transformers that would work for the job?


Thanks Brian!

Desol
Old 6th August 2005
  #28
Lives for gear
 

Hi Desol
The modules need 3 off DC supplies.
Plus 17.5
Minus 17.5
Plus 8 or 9 volts all relative to the 'ground' connection.
For 1 or 2 modules the 9 volt supply can be derived from the plus 17.5 volt rail.
I expect Brian has this sorted by now and can probably help with USA based knowledge of available 'off the shelf' supplies but I doubt the Power One modules will fit into a 1U rack box as they are too tall.
If I were doing this I would use a torroidal transformer and some regulator boards I have designed (not rocket science). Velleman makes power supply boards as kits or ready assembled. Use 2 boards designed for up to 24 volt (variable) and adjust them for 17.5. Use another board to get the 9 volts. Again the Velleman supplied transformers are too big so get a 18 + 18 torroidal.

Matt S
Old 7th August 2005
  #29
8070
Guest
Thanks for the response matt.

I am thinking of getting the toroidal from digikey. This is the link:
http://dkc3.digikey.com/PDF/T052/1432.pdf

I'm thinking of getting the 120v-25v version and regulating down from there.
Also...doesn't the toroidal adjust 120vac down to 25vac? Where do i get my dc conversion?

Would i be able to purchase some regulator boards from you?...i don't know how to make a regulator circuit for the unit...and if i attempt it...it could mean destruction or a finish time of about a year from now.....either would suck. stike heh
Old 8th August 2005
  #30
Lives for gear
 

Hi Desol
Looking at the transformer you indicate I would go for Digikey TE62064-ND which is 2 X 18 volt AC and the transformer is 25VA rated.
This gets you down to the right voltage area but is only AC and you need DC.
I would suggest Velleman K1823 regulator boards, available from www.cpc.co.uk You need 3 of them. CPC could also supply a transformer but you are probably better off getting that in the USA. (Digikey shown above).
CPC also supply power units made by Cebek but they come with a 230 volt transformer, non toroidal so you would still need to get that as well and discard the ones in the 'kit'. You would need 2 units HK00793 and one HK00792 from CPC. These would work out expensive but have the advantage of a heatsink on the regulator chips. The Velleman you would have to add heatsinks (a but of ally 2 inch square would be enough). There must be equivalent types of units in the USA and I suggest calling Brian for suggestions. PM me for other info.
Matt S
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump