Quick question about an A/B/Y box.

[pinkphiloyd]

I'm getting ready to throw one of these together:

http://www.aronnelson.com/gallery/main.php/v/TheBigMan-Layouts/abyled.jpg.html

My question is, do I want to isolate the in/out jacks from the chassis or not?  Seems I've read conflicting ideas.  Thanks all.

[familyortiz]

The passive type splitter you're building is susceptible to hum caused by ground loops created between the devices you're sending to, e.g. 2 amps. To get rid of this, folks use active circuits and transformer coupled outputs, along with isolated output jacks. In your case, it is not necessary to isolate the jacks and, depending on what you're hooking up, it may work just fine.
If you're interested, the link here is to a hum free a/b/y. Note that if you want N outputs, you only need to isolate N-1 outputs. Have fun.

http://www.diystompboxes.com/smfforum/index.php?topic=64924.0

[pinkphiloyd]

Thanks.  I'm planning on switching back and forth between, or using both channels on my DC-30.  From what I understand, hum is typically more of an issue if you're switching between or using two amps.  We'll see I guess.

[mantella]

have you looked at this one yet?

http://www.aronnelson.com/gallery/main.php/v/zpyders-veb/zpyders-perf-layouts/humfreeaby/Improved_Hum_Free_ABY_PCB.gif.html

[pinkphiloyd]

have you looked at this one yet?

http://www.aronnelson.com/gallery/main.php/v/zpyders-veb/zpyders-perf-layouts/humfreeaby/Improved_Hum_Free_ABY_PCB.gif.html

I have not.  But I am now.  Thanks.