Different Clubs - Different Hums

Amplifiers, effects, pickups, electronic components, wiring, etc.

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Dean Brown
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Joined: 3 Jul 1999 12:01 am
Location: Austin, Tx.
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Different Clubs - Different Hums

Post by Dean Brown »

Does anyone know a device that will eleminate the hum caused by bad grounding (usually at the clubs I play) and a direct connection from my amp to the mixing board? There are clubs we play with no hum problems and some that are terrible. I really like to direct connect because I can then adjust my amp volume without effecting the volume level on the board, but sometime the hum's so bad I end up using a mic.
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Blake Hawkins
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Joined: 4 Aug 1998 11:00 pm
Location: Florida
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Post by Blake Hawkins »

Dean, you need to isolate the grounds.
This can be done in several ways but some of the techniques may alter the sound of the instrument.
The traditional way in broadcast audio is with an audio transformer. Some "direct boxes" have this built in.
Or you could construct one if you are handy with electronics.
The grounds could also be isolated with
a capacitor, however, you would have to experiment to find the right value as this will alter the sound.
A simple thing which sometimes works is a "ground lifter"...one of those little plugs
used to connect a 3 wire line plug to a 2 wire circuit. However, that removes the protection you receive through the third wire.
Perhaps someone else will know a specific make and model of a "direct box" which will do the job.
Blake