Balanced Input/Output

[aremesnik]

Can I reject hum from AC Powered stompboxes, by using Balanced inputs and/or outputs. I'm want to move a few of my pedals to a rack system, and would like to convert them to Wal-Wart powered.

[aaronkessman]

i dont know about balanced I/O, but the Spyder is one way to get hum-free AC power. Check out the spyder article on www.geofex.com, also look at the GGG site.

[Mike Burgundy]

balanced lines work great to reject *cable* hum, hiss, clicks from fluorescent lihghting, radio stations.. etc. anything the cable picks up.  Powersupply hum will be inserted into an opamp no matter what, and come out of it too.
All balanced gear I know of works unbalanced inside (in a small, shielded, safe environment)  and uses balanced lines to interface with the big bad outside world.
Also will balanced lines not take out any hum or hiss or whatever *thats already in the signal*.
So no, unfortunately.
As AAron stated, a well-regulated, ground-isolated set of supplies is the way to go here.
See if a well-regulated wallwart works. Most of them aren't very regulated at all, but if you have one thats dead silent on every *individual* pedal, see if that works for all of them. If not, you've got groundloop trouble and need a special supply like the spyder.