adding a power jack to a big muff

[Coley]

is any special power filtering needed for this?
what do you think is the best way to do it?


i tried it before and it worked, but the distortion was lower and there was a very distinquishable hum. this happened with my bad power adapter, then also with a nicer 'onsespot'
do you think something may have been fried? if so, what should i check for?


thank you so much,
coley

[Brian Marshall]

is it a positive ground muff?  Most of the old black and green ones were.

you can do it, but the ground can cause problems.  When ever the muff touched another pedal my whole board would go dead for a second.

I added one to mine a long time ago, and just spliced the battery leads on to it.  It worked, and i didnt need any aditional filtering, but i have a dunlop DC brick which filters really well

[Coley]

hi, ive tried trhis over and over SO many times and the same thing keeps happening. if i wire a battery snap up to the pcb, the pedal works fine.

if i replace the battery snap with a power jack (which is brand new) with the wires going from the - on the pcb to the center lug on the power jack and the + wire from the pcb going to the outer, ground lug on the power jack. bypass is fine, and when when effect is turned on the LED comes on as usual, and you can hear the guitar and the distortion, but there is a very distinct hum.

the power adapter i'm using is a new visual sounds 9v power adapter and it works fine with other pedals.

it is plugged only into this single pedal, and not into any power strips. only the wall outlet. Just to be sure thre wasnt a problem with my adapter , house power, cables, guitar, amp, or speaker- I had a friend try it out in his house/ setup.

We were both using tube amps, if that makes a difference.

the power jack i am using is a standard black plastic 2.1 mm like the one sold at small bear electronics.  i've tried new solder- Im quite certain there are no dead joints.

should there be some sort of connection from the ground lug on the power jack to a ground in the pedal such as a pot or a place on the pcb, since the jack is plastic?

I've tried swapping the places of the two wires from the pcb, but that just shorts it out.

I'm really stumped, but It's getting me frustrated because i'm sure it's probably something simple, but i have no idea what else it could be.

Thanks for any help with this,
Coley