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Ron
 
Posts: n/a
Default Can't Stop Humming

Hi, Ross;

I only meant that a new shielded cable would probably solve my hum
problem, though
it's part of a bigger problem in that this house has a noisey
electrical environment that
affects every kind of amplifier from the very sensitive ones used in
biofeedback equipment to the guitar's amp.

Ron




Ross Herbert wrote:
On 15 Jun 2006 08:20:30 -0700, "Ron" wrote:

Arfa Daily wrote:
"Ron" wrote in message
ps.com...

Ross Herbert wrote:
On 14 Jun 2006 01:54:06 -0700, "Ron" wrote:


Ross Herbert wrote:
On 12 Jun 2006 10:53:24 -0700, "Ron" wrote:

(snip)


There is a difference - up to a point - but not enough of a one to make the
difference between a cable that's useable, because it's quiet, and one
that's not, because it causes too much hum.

All cables supplied for use with a guitar, should be fundamentally quiet,
irrespective of their price. However, a more expensive good quality one will
have better shielding in that it will have a denser-woven shield wire layer,
is likely to be more flexible, will have better quality connectors, and be
more mechanically stable, which will result in less microphony when you drag
it across, or bang it on the floor. The improved shielding is likely to only
be noticable in environments which are electrically very noisy, or have high
EM field strengths at line power frequency. Unless you are a professional
musician with more money than savvy, the very expensive cables claiming all
sorts of esoteric benefits from OF copper and double
back-peddling-triple-wound-multiple-plaited-total-150%-shield-construction
( or similar ! ), are unlikely to leave you feeling that you have got value
for your money ...

So, it's worth spending 3 or 4 times as much on a good quality cable, but
not 10 times or more on a 'snake oil' one.



Ahh... Thanks for clearing that up. I live in a hundred year-old dump
of a house and had a lot of noise problems when I tried to practice
biofeedback. I don't know if anyone makes a cheap EM field meter, but
if they did, it would probably show somewhat more 60 Hz in the
environment than that found in newer houses or houses with
better/modern wiring. So it would probably be to my advantage to buy a
better cable than the one that came with the guitar. I only paid $100
for the guitar, a guitar bag, amplifier, cable, and a DVD on how to
play the guitar-- so I didn't expect really *great* quality. So it
wouldn't hurt me to plonk down a couple dollars more for a better
shielded cable if it cuts down the hum a few dBs.

Ron



Arfa's advice is very good.

Your statement about a "better" cable cutting down the hum by a few
more dB is a little perplexing. It seems to infer that you are still
getting, or expecting to get, audible hum even after making sure that
the cable shielding is ok.

Provided you have an adequately shielded cable then you should be
hearing zero hum at all, except perhaps that which might be audible
when you put your ear cloase to the speakers with the volume up a bit.
The better quality shielded cables (eg.for guitar use) use
construction techniques aimed more at reducing noise generated due to
mechanical flexing of the shielding mesh wires (heard a scratching
noise when the cable is moved), not so much at reducing hum due to
radiated emi pickup which should be very good anyway given the usual
construction. Of course, double layer and other types of shielding can
marginally reduce radiated pickup better than a single layer mesh can,
but the improvement would hardly be dramatic.