Sacorus
phpBB Junior Member
|
 |
« on: September 18, 2009, 09:11:44 PM » |
|
Hey,
Wondering if there is an easy way to have isolated grounds (keep noise down) for a 9V daisy chain situation.
note - space is tight.
Cheers
S.
|
|
|
|
|
Logged
|
|
|
|
crochambeau
phpBB Member
|
|
« Reply #1 on: September 19, 2009, 11:11:20 AM » |
|
Most daisy chains I've seen don't provide for any decoupling from one effect to the next, so if you've an effect that treats its power rail to dirty hash and so forth, that will be shared amongst them all.
I would be more concerned over that than the shared ground.
If you want to tackle it, you could change your cabling to a parallel type feed with a small (.1 to 1uf) cap bridging the V+ and ground of each feed. Careful with going too big on the caps, your supply will have to work at charging them all up when you turn it on, so if you have lots of leads, I would err on the side of smaller caps unless your PSU is industrial strength.
|
|
|
|
|
Logged
|
|
|
|
Sacorus
phpBB Junior Member
|
|
« Reply #2 on: September 21, 2009, 03:45:39 PM » |
|
So if i start with a regulated 9V+ source @ say 1Amp, then had a small cap to gound on each supply before each parralell feed to power my pedals, my space and noise problems could be solved?
|
|
|
|
|
Logged
|
|
|
|
crochambeau
phpBB Member
|
|
« Reply #3 on: September 21, 2009, 05:09:12 PM » |
|
With a 1A regulated supply, you can probably get away with a fair amount of decoupling per branch. Is the supply fused? I'd start with a 1uf decoupling cap from V+ to ground on each line, and replace the fuse with a fast/medium blow to get an idea if you're stressing the PSU on power up.
You could, theoretically, place the decoupling caps within the effects themselves if Frankencords are a potential problem.
This all may, or may not fight noise, depending on where it's coming from...
|
|
|
|
|
Logged
|
|
|
|
Sacorus
phpBB Junior Member
|
|
« Reply #4 on: September 28, 2009, 03:51:35 PM » |
|
hmmm,
now i think about it, i already have some pretty big Caps in all the pedals i build(generally 100u to ground)
so the problem could be my Boss & MXR pedals???
|
|
|
|
|
Logged
|
|
|
|
crochambeau
phpBB Member
|
|
« Reply #5 on: September 28, 2009, 06:48:46 PM » |
|
Can you isolate the source of noise?
Sometimes it takes an entire evening of plugging and unplugging, but simply speculating about noise can reap a bunch of red herrings, you've got to dig it out.
Could be a cable, the power supply itself, could be digital noise or blinking LEDs polluting your audio ground, could be the amplifier/mixer/recorder or whatever you've got plugged into the effects loop, or a ground loop occurring between any or all of the above.
Narrowing it down to a specific unit or connection will go a long ways.
|
|
|
|
|
Logged
|
|
|
|
|
