Re: amplifier hum


"Tom Reese" <tomreese@xxxxxxxxxxx> wrote in message
news:k_KdnRXF7uy2PivenZ2dnUVZ_s-dnZ2d@xxxxxxxxxxxxxx
> I could use some advice on how to get rid of what is apparently RFI
induced
> amplifier hum. The facts of the case:
>
> two amplifiers 1. Marshall practice amp and 2. Fender Hot Rod Deluxe both
> exhibit the same hum
>
> the hum only appears when a cable is plugged into the input jack on an
amp.
> The hum is there whether a guitar is plugged into the other end of the
cable
> or not. It changes a bit when a guitar is plugged in but I assume that's
> because I've changed the characteristics of the antenna.
>
> I've plugged the practice amp into several different circuits in the house
> and the hum is there in every circuit.
>
> three different cables (Monster, Fender, cheapo) all produce hum (the
cheapo
> is by far the worst).
>
> there is a cell phone tower right next door.
>
> the hum gets worse when I hold the cable in the air and aim it (sort of
like
> aiming a rabbit ears on a tv).
>
> Is there a supershielded cable I can try to fix the problem?
>
> Is there something else I can do?
>
> thanks for any help anyone can offer.
>
> Tom Reese
>
>
these are suggestions
as hum busting can be quite a wild hair
try cutting the sheild on the cable at the end you plug into the amp
take the amp in for repair/and or sheilding
try ferrite choke around your cable
look into a transformer based humbuster like the EB-TECH
I doubt the cell tower is related to this issue
I would GUESS it is not RFI but rather EMI interference
what ever you do
do not lift the saftey ground
george


.

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