In article ,
Peter Parry wrote:
On Sat, 13 Apr 2019 13:00:37 +0100, "Dave Plowman (News)"
wrote:


Difficult to tell if the buzz is from all three speaker units, as when you
get your ear close enough to each one, it stops.

A similar problem of detecting which of a number of speakers was
producing sound from a device which changed characteristics when you
approached it was diagnosed by a length of hosepipe taped near the
device on one end and held near the observers ear at the other so you
could listen closely without interfering with the equipment.

Yup. Bit the same as balancing twin SU carbs. ;-)

But in this case anything seemed to stop the buzz as you got it near.
Which was what was so odd - I've never come across anything like it on
audio gear. That was with the XLR screens floating at one end. Connecting
them made the buzz permanent. And it was coming from all three speaker
units. Removed the mains ground from the X/O, silent as the grave. ;-)

In that
case the problem was with the infamous Sinclair X10 broadband jammer
which altered its characteristics as someone across the street moved
around their lounge.

--
*Does fuzzy logic tickle? *

Dave Plowman London SW
To e-mail, change noise into sound.