One Ascent gone quieter. Anyone heard of this before?

[Peter Ward]

Over the last few weeks one of my Ascents has dropped in volume. I don't know the amount but I would say the image has moved to 2/3-1/3. I've done sweeps on the speakers and there's no difference in sound output between the panel and woofer so I don't think it's the panel.

Has anyone ever heard of this? Where should I start looking?

Any help gratefully accepted!

 

[C.A.P]

Swap speaker cables from left to right and if sound fallows its a AMP issue.. Caps going bad. Panels slowly start to fade . It also can be a power board going bad and ML used to tell you to swap those and see if it fallows. If so its bad.. Lots of detective work finding these things out but it will identify the issue for sure..

 

[Peter Ward]

Swap speaker cables from left to right and if sound fallows its a AMP issue.. Caps going bad. Panels slowly start to fade . It also can be a power board going bad and ML used to tell you to swap those and see if it fallows. If so its bad.. Lots of detective work finding these things out but it will identify the issue for sure..

Thanks, C.A.P. I tried swapping the speaker cables. I even swapped over the speakers left to right just to check. It's definitely the speaker. I showered the panel in case it was just dirty, but I don't think it's the panel because the central image stays in the same place for sweeps from 20Hz to 20kHz (not that I can hear that high now ).

Power board would only affect the panel, I think?

So perhaps that points to caps. OK, well for now I've changed the toe-in and it's doing ok.

Many thanks for your thoughts! I appreciate it.

 

[jrsub]

Thanks, C.A.P. I tried swapping the speaker cables. I even swapped over the speakers left to right just to check. It's definitely the speaker. I showered the panel in case it was just dirty, but I don't think it's the panel because the central image stays in the same place for sweeps from 20Hz to 20kHz (not that I can hear that high now ).

Power board would only affect the panel, I think?

So perhaps that points to caps. OK, well for now I've changed the toe-in and it's doing ok.

Many thanks for your thoughts! I appreciate it.

I purchased my ML Vantages brand new and after about 6 months one speaker was suddenly 3 DB lower than the other. ML support had me swap the panels on the speakers and the problem followed. They sent me a new panel and all was well. Apparently the panels can occasionally fail for no particular reason. It has been almost 5 years since the panel was replaced and no issues since.

 

[Peter Ward]

I purchased my ML Vantages brand new and after about 6 months one speaker was suddenly 3 DB lower than the other. ML support had me swap the panels on the speakers and the problem followed. They sent me a new panel and all was well. Apparently the panels can occasionally fail for no particular reason. It has been almost 5 years since the panel was replaced and no issues since.

Thank you! So it may be the panel anyway. Of course, that would make sense since it's the sensitive bit. I'll try switching them around and see. It'll be a few days before I can get to it, but I'll report back .

 

[Bradh1]

I agree with jrsub its the panel. I had the same thing happen to one of my Montis panels. They shipped me a new one and its been fine for the last 3 yrs. Mine was the lower portion of the panel. Try putting your ear up next to the panel and see if a section isn't playing.

 

[Tosh]

http://www.diyaudio.com/forums/planars-exotics/210168-ml-sl3-intermittent-bias-supply-problem.html

On my SL3 these symptoms turned out to be a bad transformer. $16 plus shipping from ML.

 

[Peter Ward]

Sadly you're right

I've spent several days on this. I've washed the second panel, swapped panels between speakers, swapped speaker cables between left and right... I think it's come down to the panel, not least because it's ok when I stand up. A new pair of panels is £1950 from Absolute Sounds, and I don't that's a sensible solution for speakers that cost me about half that second hand. So, anyone got some s/h Summit Xs they want to get rid of? Or perhaps I could turn the panels upside down with an extension to the wiring. That might be most sensible.

 

[Tosh]

Send them to Germany for repair:
http://loudspeaker-repair-service.reromanus.net/Martin Logan.htm

 

[Peter Ward]

You're not going to believe this...

I've spent several days on this. I've washed the second panel, swapped panels between speakers, swapped speaker cables between left and right... I think it's come down to the panel, not least because it's ok when I stand up. A new pair of panels is £1950 from Absolute Sounds, and I don't that's a sensible solution for speakers that cost me about half that second hand. So, anyone got some s/h Summit Xs they want to get rid of? Or perhaps I could turn the panels upside down with an extension to the wiring. That might be most sensible.

I've messed up royally here.

After doing a dozen tests I got myself really confused. And I had that nagging feeling in my head. So this morning I did 2 tests and wrote everything down -- what I should have done from the start of course.

By swapping the two panels and testing both ways, writing things down, I've determined that it's not the panels.

Yes, the image is better standing up. Perhaps simply because the room acoustics are better up there. But the main part of the image stays to the left no matter which panel is there.

So that saves £1950. All I need now is someone to look at the crossovers and/or power supply. And perhaps improve some of the components while they're at it.

Thanks to miljac back in 2010 I have the schematic, and also some suggestions for mods (2011). Anyone know a potential expert in the UK Midlands? I was thinking Glenn Croft (he used to maintain my Leak Stereo 20s) but I'm not sure whether he's still taking on that type of work. I'll have to find out, but are there any other suggestions? Many thanks.

And sorry for messing everyone around (. That'll teach me to try things by memory!

 

[Brad225]

I'm guessing folks here are happy for you that its not the panels. Keep us updated on the progress of your issue.