calrec pq1253-8 modules..... racking

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It would be great if someone could correct the pinout i wrote earlier in this thread.
I know it takes some time but it would help us a lot...

Does someone have a link for a powersupply that would work?
I guess, it's easy to get the 16 volts and 48 V but what about the 5 volts "logic power" (whatever that means)? I couldn't find anything similar to that in the powersupply-META...

regards, Niklas
 
[quote author="Pri"]
I guess, it's easy to get the 16 volts and 48 V but what about the 5 volts "logic power" (whatever that means)? I couldn't find anything similar to that in the powersupply-META...

regards, Niklas[/quote]
The 5v would be for a chip to handle logic - ie open/close flip/flop gates etc...
I guess the best thing to is just use a 7805 regulator
 
Calrec PQ1253, PQ1785, PQ1895 Pin Listings & module descriptions.

Sorry it?s taken so long to get back onto the forum to post this info, but the working days have been a bit extended this past couple of weeks thanks to a large console project.

Some of this may be repeating and ?old-hat?, but it?s probably better than extracting info from several other posts and combining it and wondering if all has been taken into account.

I am not in a position to hand out Calrec circuits, so please do not ask.
Where appropriate, pinning and similar applications information that does not infringe intellectual property and/or copyright may be made available.

The 3 PQ modules listed are all from the M-Series of Calrec consoles. The PQ1253 only has a mic input stage. The other two have mic and line input stages. Module construction is on 2 PCBs; the smaller right-hand card contains the mic and line input stages, gain switching and source selection. The larger left-hand card has the input level trim, filters and EQ circuits. External connections are via DIN41612 connectors. Only the A-row of each connector is populated.

The pinning is as follows, blank pins are not connected. L and R signify Left and Right cards respectively. To the best of my knowledge these pin numbers are correct.


RH PCB. Input Amps.

R1. LINE SELECT. LINK TO L8
R2. MIC HI/LO SELECT. LINK TO R3
R3. MIC HI/LO LOGIC. LINK TO R2
R4.
R5.
R6.
R7.
R8.
R9. MIC/LINE PREAMP OUT. LINK TO L10
R10. CR
R11. JUMP COMMON
R12. JUMP -10dB. LINK TO R11 FOR -10dB OPERATING LEVEL
R13. JUMP -14dB. LINK TO R11 FOR -14dB OPERATING LEVEL
R14.
R15. -16A
R16. +16A
R17. CR
R18. 0L
R19. +5L
R20.
R21.
R22. LINE IN +
R23. LINE IN-
R24.
R25.
R26.
R27. CR
R28. MIC HI-LEVEL + . LINK TO R30 MIC INPUT
R29. MIC HI-LEVEL - . LINK TO R31 MIC INPUT
R30. MIC LO-LEVEL + . LINK TO R28 MIC INPUT
R31. MIC LO-LEVEL - . LINK TO R29 MIC INPUT
R32. CHASSIS


LH PCB. Trim, filters, EQ.

L1.
L2.
L3.
L4.
L5.
L6.
L7. CR
L8. LINE SELECT OUT. LINK TO R1
L9. CR
L10. TRIM INPUT FROM RIGHT CARD. LINK TO L10
L11. SET TRIM RANGE: OPEN +/-10dB, CLOSED +/-3dB. LINK TO L12
L12. SET TRIM RANGE: OPEN +/-10dB, CLOSED +/-3dB. LINK TO L11
L13. CR
L14. TRIM OUTPUT. LINK TO L21
L15. -16A
L16. +16A
L17. CR
L18. 0L
L19. +5L
L20.
L21. FILTERS INPUT. LINK TO L14
L22. EQ INPUT. LINK TO L23
L23. FILTERS OUTPUT. LINK TO L22
L24.
L25.
L26.
L27.
L28.
L29.
L30. CR
L31. EQ OUTPUT
L32. CHASSIS


+16A and -16A are the +/-16 volt audio supply rails. (+/-15V to +/-17.5V will do fine)
+5L and 0L are the +5V and logic ground supplies for switching purposes.
CR is Centre Rail; audio ground. ONLY use the CR pins at positions L17 and R17 for POWER as these generally have thicker tracks. ALL other CR pins are located next to audio signal pins and should ONLY be used for audio ground connections.
The Mic Hi level and Mic Lo level inputs are parallelled. There are usually two transformers on the RH card. These are for the mic inputs only. The line level input to the modules is balanced, but electronically coupled.
The module's Trim pot can have a range of +/-3dB or +/-10dB, depending on the linking of pins L11 & L12.

Inter-card inputs and outputs are all unbalanced.
The module final output (EQ) is unbalanced, and whilst all the outputs will drive respectably, they are intended as console internal connections, so the circuitry has been designed to match the rest of a Calrec console with regard to operating level, drive capability, interference immunity, etc. For correct external drive, further circuitry is recommended (you could just hang a trafo on the output, it would work, but it is a solution of zero-elegance).
This is the reason that the audio interface card in my set of photos is so busy. It has fully balanced inputs and outputs for the pre-amp output, filter in/out & EQ in/out.

It is worth noting that these modules have 4 separate circuit blocks: pre-amp, trim, filter and EQ.

Phantom power is applied externally, hence there being no mention of it above.

The PSU cards that are in my photos are available through my employer. If there is interest, I?ll post details.
The +/-17V PSU is designated PS1175 and can be set at anything between +/-5V to +/-30V by 2 pairs of resistors. In the event of a fault, the rails track to within 0.6V. Current is up to 3A. There are fuses (electronic) which automatically reset on removal of load faults.
The +5V (logic) & +48V PSU is designated PS1169. Depending on the regulators fitted current can be up to 3A per rail. The logic rail voltage is set by the regulator fitted (7805, 09, 12, 15, 18, 24). The +48V is a variable regulator, set by 2 resistors.
On both PSUs there are positions for load-balancing resistors when 2 regulators per rail are fitted.
Both cards can have on-board or external (e.g. front-panel) LEDs for power-OK.
 
Hey Pri,

how did you go with these modules in the end?

mine are still in storage - might build up the courage to actually get them racked and working - hard since i am working full time with gigs on the weekend and songs to finish writing.

Thank you Gareth for the information you have provided,

I'm guessing that the line driver cards that were on ebay would have been the go for interfacing these things with the real world.

I wonder if it is reasonable enough to connect the preamp out directly to the filter in/out then filter in/out to eq in/out unalanced? i figure that if they are on the same card it would be okay, then send the last output to an unbalanced to balanced output amp (like the ssm chip circuit used in the 9k project) or audix 35302 circuit ( i have a couple of these about)

i suspect it wouldn't be too crude to do so?
 
Hey Guys,

i just got a heap of calrec cards off ebay...

would anybody know which ones are suitable as output cards to rack the pq1253 modules.

i will post pics of the modules soon..

i got the following:
BL1496 (with 2x lundahl ll1517)
MB2221 (with 2x lundahl ll1517)
XL1499 (with 2x lundahl ll1517)
XL1498-2 (with 1x lundahl ll1517)

and a TN1820 (with ll1530 mic transformer + ll1517 output transformer - looks like a mic pre card)

anybody have any schematics for these?

thanks
 
hi,

i got them running. i just followed the mentioned pinout. i used a jlm 5 rail supply and some lundahls 1517 with linedrive-circuit to get symmetric +4dBu output gain.. the calrecs sound nice. had pretty good EIN of around -125dB (using 40dB gain), had some 50Hz and 100Hz hum on the line inputs, though.

it's totally worth it. if you just using it unbalanced with a little linegain afterwards in your recordingchain, it's pretty fast done..
 
These modules are intended to be run at an internal level of minus 10, 12 or 14 dB so a line output driver amplifier stage (unbalanced input) should provide this sort of amount of gain otherwise headroom is compromised. Similar with the Audix modules that ran at minus 10dBu internally as as they only uise a single 24 Volt supply rail MUST have an output amplifier that uses a transformer to get the headroom back as you can only get a signal voltage of +18dBu with a 24 Volt rail. Audix used an amplifier driving a transformer with 6dB step up ratio.
If you have hum on anything you have messed up somewhere. NONE of the modules hum in their own right. BL cards are 'line amps'. XL cards are sunning amps with transformer output. TN is the talkback mic amp (from the original desk).
 

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