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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
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
2,873 posts
 
If 1 and 3 are jumped it will cause a hum. They should not touch each other.
stuartbranson OP
183 posts
 
Still 1.6V eh? I see....Well I took the Cardas adapters apart and with the outer shell dismantled I found that the left adapter with 1 and 3 grounded and the right with the 3 lifted reduced the hum to almost nothing. So I put them back together that way and now it seems the jacketting is causing the hum so the 3 on the right must be touching the casing of the adapter. I think I will just give up and run single ended. Oh well... thanks for all the help. Learned something.
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