Posted by Lew on July 28, 2005 at 11:12:51:
In Reply to: HELP HELP!!! posted by T Moore on July 28, 2005 at 08:59:57:
It is very difficult to say what your problem is without being present in your listening room and
being able to examine your system directly. However, it sounds as though you may have
developed a problem involving the treble transformer in the faulty speaker. So, the first thing to
try is to switch the backplates between the normal and faulty speakers. If the problem then
appears in the previously OK speaker, then you have isolated the cause to something on the
backplate. Since the problem is apparently related to treble frequencies, you should look at the
connections of the treble transformer to the input binding posts. Look for a loose connection on
the underside of the backplate. Also, the resistors and capacitors that form the hi-pass filter
preceding the transformer could be faulty or short-circuited. If you have a VOM, you can check
for continuity of the wiring, value of the resistors (which might help indicate that one or more of
them has failed), etc. Your problem may be easy to solve.
You say you have M1s with U1 backplates. Since all of the speakers (M1/A1/U1 and probably
most of the smaller size speakers as well) share the exact same backplate components, I assume
you mean that you have the optional toroidal treble transformers, which are standard on U1s.