Martin Logan Aerius --no sound from ESL section

[jan.didden]

So how do I know whether I have an 'i' version?

 

[bolserst]

Should be a label on the back of the base.
The binding posts are also different...if the labels have been removed.

Forgot that I had TS parameters for the Aerius woofer somebody had posted that they received from ML tech support.

Aerius 8 inch woofer
Fs[Hz] 34.40
Qm 5.03
Qe 0.57
Qt 0.52
Rm [Ns/m] 1.35
B1 [Tm] 7.72
Re [ohms] 5.04
Md [g] 31.48
LP [dB/V] 80.10
Vas [lit.] 47.31
Le [mH] 1.21
Sd [sq cm] 222.00

The closest replacement/upgrade they found was a Visaton TIW 200 XS woofer.
TIW 200 XS - 8 Ohm

 

[tyu]

The back serial number ends with a I...also.on the panels...I have the older type post in first pic with no I any where....but the I in the number........an call logan there vary helpful....have fun

 

[jan.didden]

Mine is not the i-version, but that's OK.

It's definitely one of the woofers that scrapes.
Trying to open the back panel - is that glued or something, in addition to the srews??

Jan

 

[bolserst]

No glue, but they do tend to stick from the tight fit and gasket material.
If you take out the woofer you should be able to tap it free with a wooden dowel (carefully placed toward an edge) and small hammer.

I have heard of some people pulling them free with a claw hammer hooked under the binding posts but I haven't tried it, not wanting to risk breaking the posts.

 

[jan.didden]

I will probably screw a handle on the back to pull off the panel. Make it look as if it's standard 😊

Jan

 

[tyu]

once it pop lose.....it come out ezey.other times...it may have not been open..for 20years............I use a flat head driver...I find the side-top are botten.....push the end in the biges slot....ezey...pry a little at a time.... an it well pop lose....good luck..

 

[jan.didden]

once it pop lose.....it come out ezey.other times...it may have not been open..for 20years............I use a flat head driver...I find the side-top are botten.....push the end in the biges slot....ezey...pry a little at a time.... an it well pop lose....good luck..

Sorry, I have no idea what you are trying to say here....

Jan

 

[bolserst]

Use Google Translator: Tyu ==> English 😀

Once it(the back) pops loose, it will come out easy the next time.
It may not have been opened for 20 years.
I use a flat head screwdriver to open mine.
If find the biggest slot on the side, top, or bottom and push the screwdriver tip in and gently pry a little at a time, and it will pop loose.

@tyu,
thanks for sharing the method, and all your other ESL experience.

 

[jan.didden]

Thanks!

 

[soundchaser]

Hi guys;

A bit off topic; I had a chance to buy a working pair of these but backed out because of how old they might be since the Aerius was introduced in 1992. Assuming no damage to the circuits or the panels; how long can they last? Is DIY panel repair difficult (new membrane with resistive coating)? Also; are the woofers foam or rubber surround? The oldest of the Aerius could be 24 years old. Some foam surrounds would give up the ghost and need a re-foam after 24 years.

Thanks
Matt

 

[tyu]

Just got 2 pr of ML....SL3.$100 for the pr... one bad 15meg res in the bias feed pulled the panel output down...fixt got $1k for pr.............$20 for the pr Ascent....panels fell out ripet the wires....there playing now........I never pay more than $100...for used ML over 15 years old..... some eze fix.....most ownres think even if one panels has low output there worth more.....but new panels from ML.....2k.....
All the ML have rubber surround......out of over 15 pr only one bad bias....never bad woffer

As for reworking the panels....I have got most open with out riping the mylar.....pain in my but....to put new mylar on....you got pull all the old 3m tape off..an I would say recoat the medal.....I have never re-mylard a pr of ML....it could be done

 

[tyu]

Look I am not trying to be a smart guy.....like I could....hehe....
An I get in a Big way...that people like to build ESL panels from scratch....Vary cool...
But there a lot of of older ML,...Magnepans on CL now an thin....with a bad panel...low output...but 9 time out of 10....thay can be fixet.....an some times there looks are mint...
But today.....don't see minny people welling to put there hands on any thing it seems....
The ML SL3 I got from a guy that workes on electronics.....but he never even open them up when the one panels died......an that's how I find most....disposable...every thing.....
look if I can find an fix these things.....theres people an info ..if you just looket here...on this great site.....must less the webs .....best library on earth.....justsaying..
These older panels can .....sound dame good....have fun....spend less..right

 

[bolserst]

Gents, can I throw in a slightly OT question: what are the typical effects of a diaphragm losing tension? I have a pair of vintage ML Aerius and I find the sound from the panels constricted and much lower in level than the woofer. Should I replace the foil?

Losing tension will lower diaphragm resonance and often cause diaphragm to collapse to the rear stator which will result in lower SPL in general, and reduced output in the midrange(ie lower end of the ESL response). That being said, this is not a common problem with ML ESLs.
Typical causes for loss of ESL sensitivity in ML panels are:
1) leakage currents from dust accumulation on the spacers which pulls down the HV bias supply output.
Some folks have had luck cleaning off the dirt by giving the panels a shower.(seriously)
http://www.diyaudio.com/forums/planars-exotics/243508-building-large-curved-esl-19.html#post3993807
2) poor connection between diaphragm coating and HV bias supply contact
3) loss of conductivity in part or all of the diaphragm
Fixing these last two would require taking your panels apart.

Tyu probably has the most experience dealing with low output ML panels.
Hopefully he will chime in.

BTW, can you take an on-axis measurement @ 2m so we can see what the panel vs woofer output looks like?

 

[Andersonix]

Forgot that I had TS parameters for the Aerius woofer somebody had posted that they received from ML tech support.

Aerius 8 inch woofer
Fs[Hz] 34.40
Qm 5.03
Qe 0.57
Qt 0.52
Rm [Ns/m] 1.35
B1 [Tm] 7.72
Re [ohms] 5.04
Md [g] 31.48
LP [dB/V] 80.10
Vas [lit.] 47.31
Le [mH] 1.21
Sd [sq cm] 222.00

The closest replacement/upgrade they found was a Visaton TIW 200 XS woofer.
TIW 200 XS - 8 Ohm

If Re = 5 Ohms, that suggests it's an 8 Ohm woofer, but I'm sure the Aerius has a 4-Ohm woofer....?

 

[bolserst]

If Re = 5 Ohms, that suggests it's an 8 Ohm woofer, but I'm sure the Aerius has a 4-Ohm woofer....?

Re = 5 ohm looks about right to me based on published Stereophile measurements.
MartinLogan Aerius loudspeaker Measurements | Stereophile.com

Perhaps it is the Aerius i that has a 4-ohm woofer?

 

[Andersonix]

I agree that the Stereophile curve also suggests the Aerius has an 8 Ohm woofer.
Compare with attached SL3 curve which definitely has a 4 Ohm woofer.

 

[jan.didden]

Losing tension will lower diaphragm resonance and often cause diaphragm to collapse to the rear stator which will result in lower SPL in general, and reduced output in the midrange(ie lower end of the ESL response). That being said, this is not a common problem with ML ESLs.
Typical causes for loss of ESL sensitivity in ML panels are:
1) leakage currents from dust accumulation on the spacers which pulls down the HV bias supply output.
Some folks have had luck cleaning off the dirt by giving the panels a shower.(seriously)
http://www.diyaudio.com/forums/planars-exotics/243508-building-large-curved-esl-19.html#post3993807
2) poor connection between diaphragm coating and HV bias supply contact
3) loss of conductivity in part or all of the diaphragm
Fixing these last two would require taking your panels apart.

Tyu probably has the most experience dealing with low output ML panels.
Hopefully he will chime in.

BTW, can you take an on-axis measurement @ 2m so we can see what the panel vs woofer output looks like?

I tried to measure the bias but I think the meter drew it down, as it is high impedance (the bias source is). I measured about 1.5kV.

Jan

 

[drkumarmp]

once it pop lose.....it come out ezey.other times...it may have not been open..for 20years............I use a flat head driver...I find the side-top are botten.....push the end in the biges slot....ezey...pry a little at a time.... an it well pop lose....good luck..

I recently acquired a martin logan aerius, it had a fuse blown, replaced that with a 240V, 0.25A fast blow, its working now, the woofer of course had its surround in pieces, reformed it and once that gap was closed the sound started leaking through the dust cap side making a very irritating whining sound, took some time to find the place of defect, removed both dust caps and glued them back, now its working amazing, by the way there is no mention of ohm value anywhere on the speaker, measured it to be 5.9 ohm, so it must be a 8 ohm speaker. good solid make, very hard tough cone & dust cap. tried removing the back to get better access to the circuit broads but after trying a lot and even after hammering from inside it is obvious the back panel is glued shut and screws are added, there is no way of removing the back with out serous force which could break the back panel or the sides to which it is glued. removed the circuit board from the woofer hole to resolder the broken fuse clips.
My main question is since I have never heard a Electro static speaker, there is music from the panel part even without power cord connected, and once power is connected the sound increases a bit, and we get music at some parts of the panel while other parts remain dead, is this normal or should there be sound coming from the entire length of the panel? Thank you for any replay.