Anyone know where the best place is to buy shielded 1.5mm flex?
I am looking to try to minimise the RF hum emmitted by the mains cable when it is in close proximity to audio equipment.
Basically I want to do a couple of tests to find out if it does actually make a noticable difference.
The fact that suppliers of professional studio equipment don't carry this stuff. And it isn't used in recording studios should tell you a great deal. I've certainly seen shielded mains lead, but I'm not convinced it makes any difference at all. Oddly, you'll find that some IEC leads sold for computers actually have a mylar screen!
Now; there IS (as I'm sure many of the guys here know) a shielded cable available for doing the actual wiring... Worth having if you're building a studio or dedicated listening room... BUT..
Serious mains hum is more likely to be due to poor shielding on the audio cables. That or earth loops in the signal path. It's possible for the earthing arrangements at the location to give rise to earth loops too. And no doubt the sparks here are better placed than I am to explore the options that surround the installation of 'clean' supplies. This IS actually something that's worthwhile.
Physically you need to keep the routing of flex as tidy as possible. If mains and audio MUST cross then try to do so at 90 degrees. Don't run mains cable in the same trunking as audio. And whilst it's an absolute nonsense to spend silly money on interconnects it IS important to use good quality leads.
Small amounts of hum heard through high gain stages are generally being picked up by the transducer! Guitar pick-ups for instance are open coils the whole POINT of which is to sense changes in the surrounding EM field... Moving coil record pickups are the same....
Try canford audio for decent interconnects. Them or studio spares. Get a spark to check the wiring is clean and use a reasonable quality suppressed distribution block.
And, if you happen to be using pro equipment with the option of balanced inputs and outputs USE them! And make sure the leads you're using really ARE balanced and not just decked on one leg...
