Electrostatic Speaker Problem -- Is This Common?
Dave Lynch
Does anyone have any thoughts on the following problem?
Two years ago I bought a pair of used Martin Logan CLS I's. The
seller told me that the stat panels had been replaced about two
years prior.
About one year later, the volume output of one of the speakers
began to degrade. I was able to compensate by adjusting my
balance knob. Nine months later, the other speaker's volumn
output also began to degrade. Currently, they are both equal
but the output level is so low, they are unlistenable.
An acquaintance of mine had to replace the stat panels in his
Martin Logan Sequel II's at about three years. Is this a
coincidence?
I live about 30 miles from the coast in San Diego county. I don't
believe I have a humidity problem though. The speakers also never receive
direct sunlight. I rarely vacuum clean the stat panels but they
don't seem to accumulate much dust either. My amp (Hafler 200,
please no comments!) supplies ~100 watts per channel, well below the
200 watt maximum.
Is there a common problem with electrostatics in that the stat
panels have a known short lifespan? Is this common with
Martin Logan? Is this due to poor quality control? Is this
due to abuse?
I believe that the stat panels should last much longer than
3-4 years. Do owners of other electrostatic speakers have
to replace their stat panels often?
I spoke with a Martin Logan tech and he said that this doesn't
sound familiar, or common. He said I can trade in my stat
panels for a new (refurbished?) set for $650 (plus shipping). I
don't want to shell out this kind of money every 3-4 years!!
My local dealer also said that he hadn't heard of this problem
either. However, a long time Martin Logan dealer in the L.A.
area does know of this problem. He said that sometimes the
conductive layer of the speaker membrane will get a "break",
usually in the corners. Thus the membrane won't accumulate the
proper static charge and won't play properly. He also
thought that $650 was very fair for replacement.
Has anyone had similar experiences? Any thoughts or ideas?
Thanks,
Ken Middaugh
k...@atcwest.com
(619) 571-6749 day
(619) 749-0227 eve.
Stephen D Levene
|>
|> Is there a common problem with electrostatics in that the stat
|> panels have a known short lifespan? Is this common with
|> Martin Logan? Is this due to poor quality control? Is this
|> due to abuse?
|>
|> to replace their stat panels often?
|>
|>
I've had M-L Sequel IIs for about 5 years. There is no indication
that the electro/mechanical properties of the stat panels have
changed in any significant way. The speakers still sound as good
as they did the day I bought them.
BTW, I had these speakers for about 2-1/2 years while I lived in
the San Diego area. I lived about a mile from the coast and there
didn't seem to be any significant change in speaker characteristics
when I moved to the low relative-humidity climate in Dallas.
-- Steve
-- Steve Levene (sdle...@utdallas.edu)
-- Assistant Professor
-- Program in Molecular and Cell Biology
-- University of Texas at Dallas
F19434
If the contact was to come unstuck , as claimed , this would be the way.
Adhesive failure due to improper prep at the factory seems the only other
plausible failure mode
Michael Ritter
the net state that they have replaced the panels.
It made me wonder!?!
Alex Sokoloff
>About one year later, the volume output of one of the speakers
>began to degrade. I was able to compensate by adjusting my
>balance knob. Nine months later, the other speaker's volumn
>output also began to degrade. Currently, they are both equal
>but the output level is so low, they are unlistenable.
This might be a long shot, but:
Is where you live part of the SCAB (Southern California Air Basin)? A
guy who repairs Quads here in the Bay area told me of a pair of old
ESLs that were never abused, but died completely (no sound from any
panels) because they'd been living in LA for a long time, and the
poor air quality there wreaked havoc on them.
Randall Bradley
There may be more than one cause. The problem is that the HIGH
VOLTAGE "BIAS" supply is not supplying the several thousand
volts that is required to cause the ELECTROSTATIC effect that
make the panels produce sound.
CAUSE A) THE HV SUPPLY HAS DIED. Check it with a voltmeter.
CAUSE B) The contact to the DIAPHRAGM is not being made between
the terminal and the "mylar" sheet. Corrosive atmospheric
conditions could cause an "etching" around the terminal area
perhaps exacerbated by the "corona" effect there.(replace panel)
Or C) plug your speakers back into the AC mains.
Regards from Singled - Ended Mosfet Heaven.
_-_-randy bradley
aka BEAR Labs
ajakub...@gmail.com
20:48:18 UTC+2, מאת Dave Lynch:
Ihave had been usin my Sequel II - Martin Logan's fantastic ESLs since Aug. 1990 !!! connected to Hafler 300w per chanel amp fused by 2A normal blow fuses
all these years!!
I had my first issue with one panel only after 3 months of use, (Balance issue)
I noticed that the sound "moved" to the left area of the speaker yet, in almost a full db of sound pressure., I have contacted ML and got a brand new pair of panels shipped by airplane to Israel free of charge, after installing the new pair the speakers worked 20 years without any degradation signs until recent year after moving to my new home by the sea-shore...(28 year ) that the sound got weaker and weaker from the static section yet evenly. I have read your comments in this forum and I am going to check several parts, btw, after air-conditioning the room the sound level from the stat gets much better.
1. Power supply (Required HV voltmeter range that is not a common one)
2. Capacitance of the Hi frequency crossover's capacitors in each speaker.
(I hope the value is registered on them)
3. The "corona" damages mention before.
4. I used to work for CISCO SYSTEMS back then, and remember using a static
Electricity measuring device, I may borrow one and hope to get some
Information out of it and for your information, if you unplug the AC and the sound immediately drops it means that the problem is more likely has to do with the level of the power supply voltage.
Please contact me if you would like to share your experiences hereto.
Best Regards
Avigdor Jakubinsky
www.dorylux.com
972-54-4424848
mye...@netvision.net.il
ajakub...@gmail.com
Avigdor Jakubinsky
www.dorylux.com
972-54-4424848
mye...@netvision.net.il
ajakub...@gmail.com