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XLR/RCA adapters problem - Electrocompaniet

I have and Electrocompaniet EMC-1UP and a VAC Avatar Super.
I read that the EMC was designed to use the XLR output and sounds better when used this way. So, I decided to get the Cardas adapters to try it out since the VAC is single ended only. I plug them in and there's alot of noise which is reduced if I touch the cables which suggests a grounding problem.(?) Worse still is when I play music. There is alot of distortion. So I took a set of cables and reterminated them with XLRs (the hot and the ground) which was a bit better but still noisy unless I touched the cables. Then I plugged in the extra rca plugs while still connected through the XLRs and it cut the noise considerably. So the question is why go through all this trouble? Well the darn EMC does sound better throught the higher ouput XLR jacks. Any idea what's going on here before I open up the CDP and check if there's something wrong with the ground? Thing is is that I have good cables I would like to use but there's no way I'm going to butcher them. The EMC is still great sounding single ended but I would like to experiment.
I am relatively handy and can figure out simple elctrical problems but this is beyond me.
Anyone have any suggestions? Any other Electrocompaniet users have a similar problem?

Thanks
stuartbranson
tvad
9,467 posts
 
I owned an EMC 1-UP, and tried a similar approach with adapters and made-to-order RCA>XLR cables. Rwwear's comments are exactly correct in that not all XLR connectors use the same grounding scheme. My first set of RCA>XLR cables caused a hum because the pin configuration was not correct for the EMC 1-UP. Once I returned them with the EMC 1-UP pin configuration, the manufacturer was able to make the appropriate adjustment. Electrocompaniet provides the XLR pin configuration in the EMC 1-UP manual. You can provide this info to Cardas, or Audioparts, Inc, or other cable manufacturers and have them configure your cables or adapters correctly.

I'd suggest sending your adapters to Cardas along with a copy of the EMC 1-UP XLR pin configuration, and have the factory correctly wire the adapters.
stuartbranson OP
183 posts
 
Firstly, thanks for all the helpful information.
Second, I realize that using adapters is still single ended but I think I'm taking advantage of the 3.2V output from the blanced outs as opposed to the 1.6 V with the RCA's.

The pin configuration is on the back of the EMC and is as follows:
1 Grnd
2 +
3 -
So if I just groung the 3 pin along with the 1 should it stop the hum?
I guess I will take my Cardas adapters apart to see how they're configured and make any necessary changes.

I figured it had to bbe something with the EMC because the adapters worked fine with my friend's Wadia.

I guess this could be troubling with all sorts of gear matches. I never thought that a standard would not exist.
stuartbranson OP
183 posts
 
Well, I opened up one of the Cardas adapters and with the pin information on the back of the EMC it looks like everything is correct. 2 is the hot and 1 and 3 are grounded. Should I lift the connection of 3 to the ground?
ghostrider45
449 posts
 
Each leg (hot/cold or +/-) of the balanced connection runs 1.6 volts max. The cold or "-" leg caries a 180 degree out of phase copy of the signal on the hot or "+" leg.

A balanced input inverts the signal on the cold leg and adds it to the signal on the hot leg, yielding the 3.2 volt max signal.

The single ended adapter only uses the hot leg and thus the signal remains at 1.6 volt max.
rwwear
2,692 posts
 
If 1 and 3 are jumped it will cause a hum. They should not touch each other.
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