Martin Logan Aerius 1 help

[4RUNNER 520]

Just picked up a pair for what I thought was a fair price. gave a fair listen at the owners home (widow, new nothing) all sounded good I thought. Hook them up in my home, esl on one speaker has very very low output. have swapped left and right have checked power cord. anybody know these speakers that might point me in the right direction. Setup is: hard drive usb to Denon avr to M-1 mkii 002 to speakers.

[RodH 4,866]

I believe there is a fuse inside them.

[4RUNNER 520]

just tried to pull the back not going to be easy (too pissed right now put tools away wait till fresh mind tomorrow) thanks .... David

[aslan7 954]

Hey 4runner.  

 

Sorry to hear about that.

 

Especially difficult when there is not much user history upon which to draw.

 

Will this manual help?

 

ML Aerius i 

[RodH 4,866]

Looks like there is a fuse on the high voltage board. 

 

Also there is a MartinLoganOwners forum - tech help may be found there.

 

Hopefully it's something simple to correct. 

[4RUNNER 520]

Thanks just logged on to there site will start looking hopefully find something

[jazzman53 1,276]

Hi 4Runner,

Sorry to hear about your bad experience with the ML's.  

 

Bi-amp'd ESL's with active crossovers (like mine) are much easier to diagnose than the ML's like yours which use complicated passive crossovers.  However, certain components are common to most ESL's, even those like yours which I am not familiar with.  

 

Basically, any ESL panel requires only a driving AC voltage to the stators and a DC biasing voltage on the diaphragm to drive against, to make sound.  

 

The driving AC is provided by a large step up transformer that couples the amp to the stators.  These transformers seldom go bad but it does happen.  And I don't know an easy way to check them in the circuit.  I'm pretty much a dummy with electronics anyway.

The DC charge to the diaphragm is supplied by a power supply that rectifies your 115VAC house voltage to high voltage DC (typically 3-5 KV).  This voltage is too high to check with a standard DVM (would fry your meter).  However, if it's functioning properly its output lead should throw a spark at least 1/4" long if you bring it close to a ground.  And if you're not careful it will give you serious thrill  (there's a high ohmic output resistor that won't pass enough current to kill you but you definitely don't want to touch any part of the circuit upstream of this resistor).   A common component failure in the bias supply is a small isolation transformer (not the large transformer that connects to the stators).  This transformer should be easy to check in circuit with a DMV-- if there is no voltage on the output side when powered up, it's bad.    

 

A very common failure is a poor or corroded contact where the lead from the bias connects to the diaphragm.  This can often be corrected with a dab of conductive paint to restore the connection (like the stuff auto parts sell to patch a rear window de-icer).  

 

Another common failure is a deteriorated diaphragm coating (diaphragm won't hold a charge) but this would occur gradually over time --- not quickly as in your case.  

 

Finally, I suggest that you visit the DIY Audio Forum website, register so you can post, then go to the "Planar and exotic speaker" section and start a thread about your ML Aerius problem.  Very likely one of the gurus there ("Bolserst", "Golfnut" or "Calvin") will jump in and help you diagnose that speaker.  These guys are experts and they will walk you through diagnosing the problem. 

 

Good luck with it!

[RodH 4,866]

According to the OP, the speakers worked fine, were moved, one went sideways.

 

Sounds like some mechanical contact failure due to transport, no? 

[jazzman53 1,276]

 

 

According to the OP, the speakers worked fine, were moved, one went sideways.

 

Sounds like some mechanical contact failure due to transport, no? 

 

I agree--- most likely. 

 

 

[RodH 4,866]

I hope so for his sake!

[4RUNNER 520]

Have emailed ML direct they have been helpful walking me through simple solutions to help narrow/diagnose the problem. have also logged onto ML owners forum and started a thread there. thanks for you well wishes, will work on them again tonight fingers crossed.

[aslan7 954]

Thanks for the update 4Runner.  Sounds like you are on the right track.

 

I run a ML center channel for my upstairs system and am curious as to what the problem is with your ML's.  

 

Keep us posted. 

[jazzman53 1,276]

Here's a thread that may be helpful: 

 

ML Aerius no sound from ESL panel 

[4RUNNER 520]

 

 

Here's a thread that may be helpful:

ML Aerius no sound from ESL panel

 

Thanks interesting read

ML suggested swapping panels lt and rt done, faint panel is still faint, testing circuits is just barely out of my comfort zone will wait for reply from ML then decide whats next. thanks for the link ..... David

[jazzman53 1,276]

Not sure I understood what you did there--- but if you swapped panels and the same panel is weak (problem moved to the other speaker), then problem lies with the panel, not the electronics; in which case the problem has to be either a poor connection where the bias supply wire contacts the panel or the conductive coating on the diaphragm has deteriorated.

 

It may be possible to remove the forward stator without damaging the diaphragm. Not sure if you can, since some ML models bond the horizontal spars to both stators and the diaphragm and some don't. If you are able to remove the front stator without damaging the diaphragm, you could try placing a drop of conductive paint over the contact to restore continuity, then temporarily re-assemble the forward stator and see if that solved the problem. If the panel is then still weak, the diaphragm coating is deteriorated.

 

As simple easy fix to restore the diaphragm coating:

Remove the front stator and coat the entire diaphragm with a 50/50 mixture of water and any liquid dishwashing detergent containing sodium laurel sulfate (almost all dish detergent has this ingredient on the label). Then replace the forward stator and enjoy the music. The soap coating will conduct indefinitely and has ideal resistivity. The only drawback is it's not as transparent and it attracts dust over time so you would need to run a vacuum cleaner over the panel occasionally.

[jazzman53 1,276]

Here's a rebuild thread: http://www.martinloganowners.com/forum/showthread.php?15267-My-rebuild-of-some-Aerius-i-speakers

 

Rebuilding panels isn't all that difficult if you're mechanically inclined. Apparently, ER Audio sells a rebuild kit too. I'm not crazy about their coating solution though, as it's quite cloudy-- I prefer Licron Crystal ESD (8oz Aerosol Spray $40 at Allied Electronics).

 

 

[jazzman53 1,276]

 

 

Not sure I understood what you did there--- but if you swapped panels and the same panel is weak (problem moved to the other speaker), then problem lies with the panel, not the electronics; in which case the problem has to be either a poor connection where the bias supply wire contacts the panel or the conductive coating on the diaphragm has deteriorated.

 

It may be possible to remove the forward stator without damaging the diaphragm. Not sure if you can, since some ML models bond the horizontal spars to both stators and the diaphragm and some don't. If you are able to remove the front stator without damaging the diaphragm, you could try placing a drop of conductive paint over the contact to restore continuity, then temporarily re-assemble the forward stator and see if that solved the problem. If the panel is then still weak, the diaphragm coating is deteriorated.

 

As simple easy fix to restore the diaphragm coating:

Remove the front stator and coat the entire diaphragm with a 50/50 mixture of water and any liquid dishwashing detergent containing sodium laurel sulfate (almost all dish detergent has this ingredient on the label). Then replace the forward stator and enjoy the music. The soap coating will conduct indefinitely and has ideal resistivity. The only drawback is it's not as transparent and it attracts dust over time so you would need to run a vacuum cleaner over the panel occasionally.

 

Forgot to mention: When using the dish detergent coating, wipe it on with a a cotton ball in circular fashion.

 

Also forgot to mention: On some ML speakers the bias supply lead is just taped to the diaphragm to make the contact-- a very poor method prone to failure. Whereas, on later models they got smart and soldered the lead to a copper foil strip that runs along the sides of the panel (stole the idea from DIY'ers on the internet). The copper foil type contact practically never fails.

 

[4RUNNER 520]

Sorry for the long delay in updating, was dealing with the old owner and did not want to get to deep in case they refunded my money (they did not) they did give me a matching cinema center (no charge) so not a perfect deal but I am happy, I did get the bad panel working better is now about 8 db lower than the other, took both panels in the shower and washed then rinse with distilled water, after lots of reading seems like a common problem and fix.

Thanks Jazzman and all for the links and advice. Rebuild is more than I want to attempt will probably order new panels from ML. Give me a motor with a bad valve or bad bearing or ??? will fix ya right up, esl panels look to be a lot of learning for a one time build.