Re: 60 cycle hum in racks - stopping the insanity / share your magic

[Krispen Hartung <info@krispenhartung.com>]

> Wall -wart transformers are quite notorious for their 
noise...especially the ones Lexicon uses (someone mentioned 
the Vortex?)  When I used a larger, deeper rack one remedy I 
found was installing a power strip/surge protector 
as far to the back of the rack as possible; creating as much 
distance as possible between the wall warts and the 
equipment.  This greatly reduced the hum.

Yup..that works somewhat, did that...

> I also tried warpping the transformers in foam...didn't 
work all that well.

How about lead foil? :) Got some of that?

?Since then I have replaced all but one of my pieces with 
stuff that has internal pwr transformers. Now the only 
problem I have is with my JamMan.  My fix was to buy a three 
foot industrial extension cord from the hardware store, wrap 
both it and the cord to the JamMan pwr supply in some of 
that tubing Radio Shack and others sell for cleaning up home 
theatre cable messes (this acts as a sort of strain relief 
for the JamMan cable) and plug that into the Furman pwr 
conditioner in my rack.  The three foot extension cord hand 
out of the back of my rack, down to the floor with the noisy 
little JamMan transformer.   Sure, it does not look as neat 
as having everything conatined and hidden in  the rack, but 
there is no hum!

This will be my last resort...actually, I was going to plug 
all the wall warts into a power-strip, and then make a nice 
box to hide tha in...with the power strip main coming out of 
one end, and all the power wires to the effects coming out 
of the other end. This could just be tossed in back of the 
rack when moving.

> As far as other ground loop problems go, HumFrees really 
do work wonders in isolating gear from the rack chasis.

As I said in a past email, if you read up on how these so-
called HumFrees work, and what they are made of, you'll 
realize that those capalistic shysters are charging about a 
1000% markup on the actual costs of the materials. Go to the 
hardware stores and buy a handful of nylon washers...put 
them on both sides of the "ears" of the effect, one washer 
beneath the scew, and another behind the ear. 

Kris

> I am thinking quite seriously of checking into the Ebtech 
devices for hum removal on the JamMan supply.  My question 
is whether it will remove  "transformer hum" or only deal 
with ground loop hum (which I think are to different little 
noise gremlins...) Any one have experience with these?

Max