new panel - new resonance

[lpaudio2]

Well I have I would guess 40 hours +- 10 hours on my new panels. Im hearing a lower bass resonance. It could be a result of the increased stat panel output or (in which case I will brace the cabinet ) or I noticed that the weather strip between the panel and frame is not that supple and kinda compressed, so im wondering if i need to add, to help isolate the stats from the bass section - wondering if the color is coming from that... hard to know. maybe it will go away as they break in?

Ive got new caps on order too, cant wait till they come. Went with a 10 and 15 uf set of claritycaps. Im not touching the 5uf as thats just a shunt between - and + and has quite a few other parts before it, also clarity does not make a 5uf.

 

[Neil H]

I don't know your particularly model of Martin Logans but I have replaced panels on Quest's and didn't hear anything like you are hearing. The non-broken in Quest panels simply sound a bit ear piercing at first with accentuated highs and no real warmth. Everything snapped into place around 30 hours but resonance was never the problem.

I suppose that such a problem could happen as a result of room interaction during breakin but it sounds to me like something else. When I first go by Summits I did hear a resonance and this turned out not to be a breakin problem, but instead a faulty panel. There were crinkles in the the mylar at the bottom right of the panel which made it sound like there was something wrong with the bass driver when it was really the panel itself. I had the panel replaced and everything has been fine since.

As I said I don't know anything about your speaker but perhaps you should be looking for something physically wrong with either the panel or the way it has been fitted.

 

[VanDaRo]

New panels sound a bit brash at first. But at 40 hrs, I'd think they were calming down significantly. So I'd say to pull the interfaces out and make sure that all of the transformers and circuit boards are screwed down nice and tight. I had a buzzing issue a few years ago (at certain frequencies) and solved it with a Phillips-head screwdriver....

~VDR

 

[JonFo]

The other possible reason for a resonance is if the panel has not been well mounted to the frame. Several older models leave bit of slop in the panel to frame interface that could vibrate. Some even used some stuff that looks like window weather-stripping to seal the stat to the frame. If you did not replace that material when swapping, the old stuff might have enough 'give' to allow the panel to vibrate against the frame rails.

Also, how well the rails are on could have an impact. So don't discount a mechanical source for the root cause.


Let us know how it goes.

 

[Tube60]

I had a buzzing issue a few years ago (at certain frequencies) and solved it with a Phillips-head screwdriver....~VDR

When I first got my Sequels, there was a really annoying buzz that I couldn't find for awhile. Finally I found the problem when I pulled the electronics out to dust them off. A wire was trapped between the circuit board and the metal panel; been that way since new. An easy fix, with, you guessed it, a Philips-head screwdriver. And the previous owner never noticed. D'oh!
Goes to show that sometimes a little sleuthing can find interesting things!:rocker:

 

[lpaudio2]

I did replace the weatherstripping. There is still a resonance. I think what happened is that the old panels were down so much, that the new brighter sounding panels are making cabinet vibrations more apparent.

I suspect the wings are causing it, I am building a quick brace with threaded rods to see if that fixes it.

Is it normal for there to be some resonance? Its at the lower end of what the stat panel produces (I can power down the amps that run the bass - and its still there with just the ESL)