Disklavier

There are actually two noises.  The main noise comes from within the 
amp box somewhere.  The second noise is as you described:  a 
vibration caused my the wire mesh and other metal surroundings.  I 
can quiet the second, but not the main source.  This is a very 
intermittent problem - happens about one hour for every five of 
use.  Any other ideas would be greatly appreciated.

J. Young

--- In disklavier@yahoogroups.com, "dkvtech1ab" <fatcheson@a...> 
wrote:
> 
> Hello J. Young
> 
>  Is it a HUM or is it an occasional rattle-a vibrating sound that
> maybe mistaken to be a HUM-.? When you hear the HUM which is 
comming
> from the AMP unit underneath the piano, simply go underneath and 
touch
> the mesh that covers the amp, see if you can make it change. 
Reason?
> These units have Hi frequency shunts-shunt being used loosely to 
make
> a point- that are like litlle donuts in which the wires are wrapped
> and cancels RF. Now, at times when the distance between the mesh 
and
> the shunts are just far enough but close enough to move away and 
come
> close just as the field is changing polarities, you will hear a 
rattle
> type hum from the AMP but not from the speakers. Same principle as 
a
> voice coil just not musical!!!
> 
> I hope this helps!!  
> 
> DKV1AB
> --- In disklavier@yahoogroups.com, "FrJJY" <frjjy@y...> wrote:
> > 
> > I have a new DC1A with an intermittent problem:  There is 
> > occasionally a hum that comes from the amplifier - perhaps the 
power 
> > supply.  The noise does not come through the speakers but comes 
> > directly from the amplifier box.  Has anyone else had this 
problem?  
> > Unfortunately, the problem disappeared when my tech arrived, but 
of 
> > course, reappeared after he left.  Any solutions?
> > 
> > Thanks.
> > 
> > J. Young