The No.1 Website for Pro Audio
 Search This Thread  Search This Forum  Search Reviews  Search Gear Database  Search Gear for sale  Search Gearslutz Go Advanced
Calrec C2 line in/out balancing Virtual Instrument Plugins
Old 8th September 2016
  #1
Here for the gear
 

Calrec C2 line in/out balancing

Hello guys, so I just purchased 2 Calrec C2 consoles for an amazing price. Complete schematics and pin details for the EDAC connectors. I am trying to wire this thing up but the line ins/outs only have 2 connection pins. The mic inputs have +, - and a chasis connection. The manual says all connections are balanced. I did hook up a cable to the line inputs and it sounded great. I'm just concerned that I'm going to be wiring it up unbalanced.
Can anyone shed light on this for me?
Old 8th September 2016
  #2
Lives for gear
 
Geoff_T's Avatar
 

Quote:
Originally Posted by Fractalvision View Post
Hello guys, so I just purchased 2 Calrec C2 consoles for an amazing price. Complete schematics and pin details for the EDAC connectors. I am trying to wire this thing up but the line ins/outs only have 2 connection pins. The mic inputs have +, - and a chasis connection. The manual says all connections are balanced. I did hook up a cable to the line inputs and it sounded great. I'm just concerned that I'm going to be wiring it up unbalanced.
Can anyone shed light on this for me?
Hi

I'm pretty sure a pro audio company like Calrec that supplied consoles to the BBC would have fully balanced in and outs. So use the +/- for the balanced signal, keeping the cable pattern constant to avoid a phase reversal and most likely the shields of your cables will terminate to ground at the remote equipment end and don't need tying down at both ends.

Old 8th September 2016
  #3
Here for the gear
 

Geoff, thank you for your response. That is very helpful.
Old 8th September 2016
  #4
Lives for gear
 
Geoff_T's Avatar
 

Quote:
Originally Posted by Fractalvision View Post
Geoff, thank you for your response. That is very helpful.
Hi

I did some digging and came up with the fact that the C2 and other recent Calrec desks use balanced inputs on pairs but only have 4 'ground' pins on the EDACs, the 4 on the centreline of a 56 pin.

The cables used for the original installation are multiple twisted pairs with only an overall screen (old BBC type cable from back in the day).

Typical layout is :AB,CD,EF,JK with H being the screen connection, first pin of pair is hot. AB is left input/output, CD being right channel.

Old 9th September 2016
  #5
Lives for gear
 
Wiggy Neve Slut's Avatar
 

I'm sure Matt Syson can help out here!
Old 9th September 2016
  #6
Here for the gear
 

Thanks for the help. Yes I see where it says first pin of pair is hot in the manual, and it shows A (hot) B (cold). But that doesn't seem to apply to the channel inputs. It shows them as being chassis. The send and returns use A B. Now the cable that came with it is wired the opposite, using a red wire on the 2nd of the pair and a black ire on the 1st.
I'm going to post a couple of pictures.
Old 9th September 2016
  #7
Here for the gear
 

Here they are. I couldn't figure out how to upload pics
Attached Thumbnails
Calrec C2 line in/out balancing-image.jpg   Calrec C2 line in/out balancing-image.jpg   Calrec C2 line in/out balancing-image.jpg  
Old 9th September 2016
  #8
Here for the gear
 

I have been hooking up a few channels to test things out. The line inputs work great. The mic input makes a lot of buzz and is unusable. Not sure what I'm doing wrong. But mics work on the line input as well. But I doubt the 48v will go to the line input. So I'd like to figure out why my mic inputs are buzzing. I've only hooked up the line and mic inputs on channel 1 & 2 and both mic inputs buzz. But like I said the line inputs work great. The cables that came with it are 56 ELCO or EDAC, not sure what the difference is.
Anyway I'm going to be cutting one end off and soldering some XLR's and TRS cables to them. The inserts I'll solder to a txt patch bay, that I'm currently looking for a deal on eBay for.
So I hooked the F pin of channel 1 up to pin 2 on the XLR because the cable wire was red bad the black wire to pin 3 and the chassis pin to pin 1. But my microphone is buzzing.
Old 9th September 2016
  #9
Lives for gear
 
Geoff_T's Avatar
 

Quote:
Originally Posted by Fractalvision View Post
Here they are. I couldn't figure out how to upload pics
Hi

That wiring schedule looks like someone compiled it on a Friday afternoon between visiting the pub for lunch and wanting to leave early.

If it was a Neve drawing, it would have had a sheet for each connector rather than combining multiple functions on one sheet.

If you have a diagram of the channel showing the wiring to the connector that would help. My best guess is there's a flip between one audio path connection and a ground connection.
Old 9th September 2016
  #10
Here for the gear
 

Not sure if this helps. :(
Sorry I don't have much experience with this stuff. I appreciate your effort.
I don't see any reference to the pins
Attached Thumbnails
Calrec C2 line in/out balancing-image.jpg  
Old 9th September 2016
  #11
Here for the gear
 

The schematic is pretty large and can't fit it all in one picture
Old 9th September 2016
  #12
Here for the gear
 

This is the mono mic/line module
Attached Thumbnails
Calrec C2 line in/out balancing-image.jpg  
Old 9th September 2016
  #13
Here for the gear
 

The manual doesn't have a connector "map" that shows me which pin is which letter. I've found a few on the internet and found this one that seems to jive with what's going on with the Calrec. This is what I'm using.
Attached Thumbnails
Calrec C2 line in/out balancing-image.jpg  
Old 9th September 2016
  #14
Lives for gear
 
Geoff_T's Avatar
 

Hi

It's not easy doing this by remote control but I'd suggest unplugging the mic cable and see if the noise goes away. If it does the issue is with the wiring of that cable.

Good luck!





Quote:
Originally Posted by Fractalvision View Post
Not sure if this helps. :(
Sorry I don't have much experience with this stuff. I appreciate your effort.
I don't see any reference to the pins
Old 9th September 2016
  #15
Here for the gear
 

Ok I'm gonna try to wire it differently and see what happens. I think if I just keep experimenting I'll hit the right spot.
Thank you for your responses Geoff.
Peace
Old 9th September 2016
  #16
Here for the gear
 

Here it is by the way.
Attached Thumbnails
Calrec C2 line in/out balancing-image.jpg   Calrec C2 line in/out balancing-image.jpg  
Old 9th September 2016
  #17
Here for the gear
 

Gee whiz, not sure why they uploaded sideways but.....:(
Old 10th September 2016
  #18
Here for the gear
 

Ok so I figured out my buzzing mic input. The problem was that I'm an idiot.
Old 10th September 2016
  #19
Lives for gear
 
MickeyMassacre's Avatar
Quote:
Originally Posted by Fractalvision View Post
Ok so I figured out my buzzing mic input. The problem was that I'm an idiot.
oops wrong thread!
Old 28th January 2017
  #20
Here for the gear
 

Hello, have recently buyed a Calrec C2 (I think) and need help in find a proper edac to xlr loom.
Attached Thumbnails
Calrec C2 line in/out balancing-img_4865.jpg   Calrec C2 line in/out balancing-img_4863.jpg   Calrec C2 line in/out balancing-img_4862.jpg  
Old 6th February 2017
  #21
Here for the gear
 

Majoroak you can email me and I can see if I can help you. I'm not on this site often. [email protected]
Old 6th February 2017
  #22
Lives for gear
 

Hi
You will have to make the looms as they are not a 'standard' as such. As was noted earlier the mic EDACs are wired differently to line circuits. The lines are up to 24 circuits on a 56 pin with only 4 'centreline' pins and a handful of others as grounds. The mics are 8 (?) circuits on a 56 with lots of grounds.
The reason the schedule looks complicated is that the functions change depending which type of module you have plugged in, stereo or mono. The manual is 'standard' unless particular mods were made for customers.
Matt S
Top Mentioned Products
Topic:
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