Martin Logan SL3 = dead => help - Page 3 - diyAudio
Go Back   Home > Forums > Loudspeakers > Planars & Exotics

Planars & Exotics ESL's, planars, and alternative technologies

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 15th October 2010, 06:32 AM   #21
nac134 is offline nac134  Canada
diyAudio Member
 
Join Date: Sep 2008
I didn't want to trash someone elses post, I'm new to the whole forum thing. But I share Steve M's sentiments.
I took a second look at your original post. Whats happening is that the power supply is charging up, and once it reaches a certain voltage (it only takes a few seconds), its arcing, and the process starts over. The volume is low because the panels arent charging properly. Somewhere the insulation between the wire that charges the panel, and one of the wires that carries the signal, has been compromised, and the electricity is jumping across. You need to find out where this is happening. The spark will be visible. If you cant see it from the outside, you are giong to have to get inside. Unplug it for 30 minutes before you go to work on it, to allow the charge to dissipate. If I recall correctly, the sl3 has a big wood piece on the back with screws all the way around. Is this correct?
  Reply With Quote
Old 15th October 2010, 03:39 PM   #22
enilsen is offline enilsen  Sweden
diyAudio Member
 
Join Date: Oct 2006
I also agree with nac134. You need to read the beginning of the post to understand what is the problem here. Hence why I suggest using this none intrusive test to see if the static charge does not reach the membrane. The test is audible which will allow you to hear where the discharge is happening the fastest. Any discharged area will produce little or no sound. The other areas will sound normal (with the music playing). Sometimes you need to hear what you can’t see.

It's not the stators you are going borrow the charge from, but the statically charge membrane. The stators on the ML's are very well insulated and I doubt anyone will get zapped from the stators unless they break the insulated coating. If anyone has been electrocuted from an electrostatic speaker it was not a Martin Logan as far as I have heard.

A mosquito zapper can also be used to charge the membrane if you don’t feel comfortable using the other panel. Just connect a crocodile clamp to the center feed on the mosquito zapper and lead the charge to the membrane using a test cable with a flat metal tip. Mosquito zappers can be purchased almost everywhere these days and are powered by a couple of AA batteries. They also produce thousands of volts but if handled carefully should not pose any harm to people.

BTW. Both these methods have been tested by myself on ML speakers with great success.

Last edited by enilsen; 15th October 2010 at 04:00 PM.
  Reply With Quote
Old 15th October 2010, 04:15 PM   #23
diyAudio Member
 
JonasKarud's Avatar
 
Join Date: May 2008
You can use a cheap contactless voltage tester to check if there's a charge on the membrane, at least I can do it on my Diy speakers with M-L membranes.

Picasa Web Albums - Jonas - Drop Box

Yes, I know that these testers are for AC voltage, but they work on Esl:s also! (Maybe due the high voltage or the ripple from the HV ladder.
Attached Images
File Type: gif p-89%20tester.gif (6.0 KB, 217 views)
  Reply With Quote
Old 15th October 2010, 06:03 PM   #24
nac134 is offline nac134  Canada
diyAudio Member
 
Join Date: Sep 2008
You dont need to test anything. Knowing whether or not the panel is charging will not help you. You need to find out where the arcing is happening.
  Reply With Quote
Old 16th October 2010, 09:09 AM   #25
enilsen is offline enilsen  Sweden
diyAudio Member
 
Join Date: Oct 2006
I disagree. You must first exclude any discharge (arcing) in the panel itself before poking around inside the electronics. ML speakers can discharge the static charge anywhere around the perimeter or where the spacers are located. This doesn't have to show up as a blue flash of light like in other electrostatics.

Once you confirm that the membrane can hold a charge over the whole panel you can proceed to investigate else where. This would involve dismantling the speaker.

Currently we only assume the popping sound is cause by arcing, but the other clue Per Anders said was the low volume from the panel. This is a typical sign when the static charge does not reach the membrane.

Some causes for this are:

1. The aluminum strip and wire at the bottom of the panel does not conduct the static charge to the membrane. (old conductive coating no longer works)

2. High humidity in the room has made the exposed spacers conductive thus draining the static charge to the stators. (de-humidifies will fix this)

3. Some one got water on the speaker itself and this has run down the membrane into the bottom spacer. (in 2 to 3 weeks it might start working again)

4. The speaker has taken on a new roll as a giant mosquito zapper and is finally saturated with insects. (I suspect Per Anders thought about this when he vacuumed the panel)
  Reply With Quote
Old 16th October 2010, 10:09 AM   #26
diyAudio Member
 
JonasKarud's Avatar
 
Join Date: May 2008
Yes, if there's a charge on the membrane it must be something wrong
with drive transformer circuitry or cables to the stators...
  Reply With Quote
Old 17th October 2010, 03:31 AM   #27
diyAudio Member
 
Join Date: Apr 2003
Location: Eastern Pennsylvania
Per-Anders,

Your problem might be due to the high-voltage step-up transformer contained within each speaker. If this transformer has turns which have become shorted this could produce both the 'pop' noise and the reduced panel volume. Temporarily swapping this transformer with the identical one from the other speaker would prove or disprove this possibility.
__________________
Ken
  Reply With Quote
Old 23rd August 2011, 12:48 AM   #28
diyAudio Member
 
Andersonix's Avatar
 
Join Date: Jan 2004
Location: Silicon Valley
P-A: Any update?
  Reply With Quote
Old 5th January 2012, 07:44 AM   #29
tibell is offline tibell  Sweden
diyAudio Member
 
Join Date: Jan 2012
Location: Gothenburg
Hi Per Anders

I have the exact same problem with one of my dadís SL3 speakers.
I just found this forum treed when I searched for some information about Martin Logan, and I saw that you also live in the same town as me, I was thinking about if this could be some kind of virus?

Therefore Iím very interested to hear if you managed to solve this problem?

Dan Tibell
  Reply With Quote
Old 28th January 2012, 12:52 PM   #30
john65b is offline john65b  United States
diyAudio Member
 
john65b's Avatar
 
Join Date: Jan 2005
Location: Chicago
Hey all, I have just acquired some old CLS Panels, and have built a bais and power supply - a hybrid from Jazzman's site and Mark Rehorst's site. A 20VDC Laptop power Supply to a LM317 Voltage regulator to a Emco DC50 DC to HVDC converter to get the 5KV Bias (a la Rehorst). Works great. The Audio Transformer is a pair of 120V - 6V transformers (Antek AN-1206, a la Jazzman).

My panels are low output and a bit distorted. My plan is to open the panels and clean / recoat them. I hope that the mylar is intact and still glued all around.
__________________
All right, but apart from the sanitation, medicine, education, wine, public order, irrigation, roads, the fresh water system and public health, what have the Romans ever done for us? Life of Brian
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Need help with Martin Logan speaker JariV Multi-Way 10 18th November 2008 06:04 PM
Martin Logan SL3 Woofers? jbeckley42 Planars & Exotics 7 24th October 2007 02:58 PM
martin logan csl flodge Planars & Exotics 12 13th November 2005 02:59 PM
Martin logan ascent jouch Planars & Exotics 0 25th March 2004 07:02 AM
X-Aleph and Martin-Logan Faber Pass Labs 2 7th November 2002 08:40 PM


New To Site? Need Help?

All times are GMT. The time now is 06:26 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2