XLR cables are picking up radio/TV hash...


Hi everyone,

This is an ongoing dilemma so I'll try my best to be short and to the point. I recently got 1 m Cardas Neutral Reference XLR to use between my Sim Audio W-5 power amp and my Marsh P2000b preamp. My system sounds a lot better, but I am picking up audible radio and/or television sounds on my speakers (Quad 22l). I do not have a functioning cable tv connection (I don't have a television, period!) but my power outlet is near a cable tv jack. Could this be the problem? I read on some other fourm that the cable connection may need to be grounded.

I have tried to go troubleshoot in a thorough fashion; I tried using cheat plugs; I disconnected all my cables, power cords and speaker wires, then reconnected them slowly. I discovered that only when I powered up my preamp did I got noise...and it did not increase or decrease whatever I did with the volume knob. Something is obviously acting as an antenna and picking up signals.

I think this may be a problem unique to the Sim Audio W-5; it has two sets of RCA connections, where, if you choose you can use both sets in a sort of single-ended "balanced" configuration. There are two dummy plugs inserted into the negative inputs, and the positive inputs are used in a normal single ended configuration. Thing is, I had no noise when using the Marsh and the Moon in single ended mode. I am certain that my new Cardas cables are fine...I had them checked out at a dealer...I also replaced them with a brand new pair of Transparent balanced cables with the same resultant hash. I did find that if I placed the two dummy plugs into either the left or right set of RCA connections I did not get any hash on that channel but it obviously degraded sound quality as it shorted out that particular channel.

I have had suggestions ranging from changing my preamp with another balanced one to check to see if that is having problems, to using Cardas caps to cover unused XLR and RCA connections, and even clamping ferrite clamps on the XLR interconnects.

Also, I am using a Rega Planet 2000 (in single ended config) and a Rega Planar 3 with a Pro-ject Phono Box SE; I am pretty sure they are not the cause of my problems but I am just being thorough for the record!!

Please help!
Thanks,
Khalid
128x128aurlieus
Khalid,

It's your pre-amp's xlr outputs. Contact Marsh and see what they say, could be something miss wired internally that is ok when you run single ended. I don't understand your 'jumper' description, I thought newer W-5's had a switch to select xlr or rca inputs. It's a bummer problem since both your W5 and the Marsh are suppose to have improved sound if run balanced. Go back to SE connection in the meantime so you don't go crazy. ;-)
Hi Nick,

It has been a rather depressing couple of weeks. Let me explain:

- I tried out the Cardas XLR and RCA caps, no luck!
- I took my pre amp to my local hi end store and hooked it via the XLR interconnects I use at home, perfect, no issues, no noise!
- I will take both my amp and pre amp to the store and basically try to recreate conditions at my house, if there is a problem then I am on the right track, if not then there is something very wrong with wiring at my house which could mean an expensive visit from the electrician!

Keeping my fingers crossed!

K.
Good luck, sounds like a nightmare. There are electric plug testers that just plug in the wall and give you green light or red light to check wiring. Just ask at a hardware store. Taking the whole set to the shop or at least some friends house may be the only way to figure it out.

Cheers, Nik
Hi Nick,

It seems all my components are totally fine - they worked perfectly at the store with all the cables I use at home in balanced mode, no noise issues what so ever. Not a thing wrong with my electrical socket either, I got a Transparent Labs line tester installed on my outlet and the line was diagnosed as having no problems.

Even the most well read and hardcore stereo guru is stumped by my dilemma! No one seems to have an answer; I am hoping that if I install a new audiophile power socket it might help though chances are slim!

Still hoping,

Khalid (I may have to move house!)