Help with Martin Logan Quests.

I would call Jim Powers at Martin Logan. Tell him the problems and the results--particularly the last story. While, I can share my experience with my Martin Logans (and a few friends), he hears hundreds of experiences and works to resolve them. He is a great resource and can likely tell you if it's the panels or possibly something else. My guess is that it's the panels and the combination of high humidity--but would be interested in what Jim tells you. He can also tell you what circuit updates were made and if they make sense for you. Your speakers may not have the auto off/on which could be a significant upgrade being in a high humidity area--they increase panel life quite a bit. Mine didn't have this either, but I just created a manual method that I used to accomplish the same thing.

It sounds to me like you have a major humidity problem. Before replacing anything get a voltmeter and a spl meter. If you have a noise generator or a test CD find the 2.83 volt output level at the output terminals of your amp (do this on a "dry" day). Then measure the speaker output with a spl meter at that level. On a wet day repeat the procedure. If the panel outputs are dramatically different you have a major humidity issue.

Iam glad you posted this my problem on quest is on speaker
it will play and then suddenly the sound would go down from
top to bottom and will hear only a little sound but its
tricky because my plinius one channel also went down
this is the side that is connected to the speaker that
got the problem,other side is ok. my guest maybe its the
panel although i doubt it, i think maybe some parts inside.
good luck,

I would like to thank everyone for their comments.

It has been a week since the problem occured, and the speakers are working fine. I think it was a humidity problem as described in an earlier post. I still think I need to begin considering new panels, but can probably squeeze a little more life out of these.

Best regards.

I own a pair of original ml quest also. About a year ago one of the speaker started malfunctioning (no sound). Haven't done anything to them (too busy). But I did speak with the ML rep and he indicated it may be the power supply. He suggested swapping the boards with the good speaker to narrow down the problem. Also, like everyone saids that the panel needs to be rebuilt. good luck