Shackman reromanus VLC-Coating Liquid PMMA 2.5
I'm posting this on behalf of harry_at, a member of diyAudio.com but he's unable to post right now (because of a login problem).
For the record, I had similar experience with the Shackman (Reromanus) coating.
Hi folks,
I'm a longtime Quad Esl-63 enthusiast and owner.
Last year (June) I have ordered VLC07 and VLC09 from reromanus to do some experiments. After some days VLC07 (Art.Nr.:45701) was delivered and should give a surface resistance of 10^7 Ohm
In the first hours and days the sound was very promising, but then the sensitivity of the Quad got lower and lower. After opening the panel, I saw that the coating has lost its "grip". You can see (attached picture) that the coating is concentrated only in small areas. Nothing in between. The surface resistance was way to high. It was humid at that time, but a coating which is not adhering to the film and/or is not wetting the film, is not the
best thing for Esl speakers. And it didn't have the desired and promised resistivity for the Esl-63.
Of course I told that Mr. Römer and he replied that the coating was produced with a wrong formulation. They will make a new one. No problem I thought, lets wait a week or two and then I will get a new bottle. No way! Some weeks later he didn't answer my emails. No money back, no new coating.
But the story does not end here. Eight months!!! later I got a new formulated VLC07 bottle (picture attached). Life can be so wonderful! But the surface resistance of this coating is 10^11 and not 10^7 and it smells like a washing detergent...and it doesn't stick to the film...and it doesn't really dry...
And if you are wondering what happened with the VLC09 order? Yes, I'm still waiting and waiting and waiting...
So here's my deal folks: I still have the old and the new VLC07 coating. Drop me a mail which one you will have and I will send it for free worldwide. The "best" things in life are free...Take your choice and try yourself.
Best regards,
Harry
You can reach Harry by sending a message with the diyAudio contact page, his moniker is harry_at.
I'm posting this on behalf of harry_at, a member of diyAudio.com but he's unable to post right now (because of a login problem).
For the record, I had similar experience with the Shackman (Reromanus) coating.
Hi folks,
I'm a longtime Quad Esl-63 enthusiast and owner.
Last year (June) I have ordered VLC07 and VLC09 from reromanus to do some experiments. After some days VLC07 (Art.Nr.:45701) was delivered and should give a surface resistance of 10^7 Ohm
An externally hosted image should be here but it was not working when we last tested it.
In the first hours and days the sound was very promising, but then the sensitivity of the Quad got lower and lower. After opening the panel, I saw that the coating has lost its "grip". You can see (attached picture) that the coating is concentrated only in small areas. Nothing in between. The surface resistance was way to high. It was humid at that time, but a coating which is not adhering to the film and/or is not wetting the film, is not the
best thing for Esl speakers. And it didn't have the desired and promised resistivity for the Esl-63.
An externally hosted image should be here but it was not working when we last tested it.
Of course I told that Mr. Römer and he replied that the coating was produced with a wrong formulation. They will make a new one. No problem I thought, lets wait a week or two and then I will get a new bottle. No way! Some weeks later he didn't answer my emails. No money back, no new coating.
But the story does not end here. Eight months!!! later I got a new formulated VLC07 bottle (picture attached). Life can be so wonderful! But the surface resistance of this coating is 10^11 and not 10^7 and it smells like a washing detergent...and it doesn't stick to the film...and it doesn't really dry...
An externally hosted image should be here but it was not working when we last tested it.
And if you are wondering what happened with the VLC09 order? Yes, I'm still waiting and waiting and waiting...
So here's my deal folks: I still have the old and the new VLC07 coating. Drop me a mail which one you will have and I will send it for free worldwide. The "best" things in life are free...Take your choice and try yourself.
Best regards,
Harry
You can reach Harry by sending a message with the diyAudio contact page, his moniker is harry_at.
Arend-Jan, thanks for the follow-up. This is a classic example of the effects of no surface pretreatment.
Calvin, a Tesla coil can be relatively easily constructed. That's all a corona treater is anyway.
Calvin, a Tesla coil can be relatively easily constructed. That's all a corona treater is anyway.
This is a classical example indeed.
Please note the measuring glass '' package''' Reiner Romer uses
This expensive high quality type of glass is used for quantitative analysis.
The thin line at the upper part of the glass is used to adjust the volume very precisely at 10,00 ml. If the hollow meniscus of the fluid level (the lowest level) 'touches' the thin line you have 10,00 ml. Of course there are larger values than 10 ml, all calibrated.
Please note the measuring glass '' package''' Reiner Romer uses
This expensive high quality type of glass is used for quantitative analysis.
The thin line at the upper part of the glass is used to adjust the volume very precisely at 10,00 ml. If the hollow meniscus of the fluid level (the lowest level) 'touches' the thin line you have 10,00 ml. Of course there are larger values than 10 ml, all calibrated.
I thank You, arend-jan, for showing the Shackman (Reromanus) coating.
Glad I didn't order it, but wanted a sample instead!
Now I do not want a sample.
Glad I didn't order it, but wanted a sample instead!
Now I do not want a sample.
SY said:
Yep, but I compare it to a conventional and more appropriate HDPE package which is cheaper, lighter and can't break into peaces.
There could be reason of course to do it this way, I don't know.
Got the exchange backward (I'm not happy about the weak dollar). $3.50 = 2E50. Though we don't pay VAT, so maybe it evens out.😉
JonasKarud said:
Hello Jonas Karud,
A second attempt,
are we talking about the bright pink coloured coating called 'Karud coating' distributed until recently by the company Audio4 in the Netherlands??????
Hi MJ,
are you still producing your EC coating? (I heard from someone that you stopped selling it??).
How would you go about making a 'modern' DIY coating with a resistance of about 1E10-1E11? Do you think it's possible?
are you still producing your EC coating? (I heard from someone that you stopped selling it??).
How would you go about making a 'modern' DIY coating with a resistance of about 1E10-1E11? Do you think it's possible?
Well, I have never called it the Karud coating, because it was a Diy product, not intended for commercial use. I did send a 1.5 liter bottle to
the Netherlands, but I do not know if this was distributed from there.
the Netherlands, but I do not know if this was distributed from there.
I sent free samples to folks in order to get an opinon on how they thought it worked, but received very few answers.
The ones I did get were very positive about the coating, and I did not receive any bad judgements, not one!
I have speakers in my living room that have this coating, which now has played for 4,5 years.
These speakers are by the way built in a special manner for testing different coatings and has detachable stators held in place with magnet strips. I have been told that this arrangement is patentable but I can take some photos if anyone is interested.
The ones I did get were very positive about the coating, and I did not receive any bad judgements, not one!
I have speakers in my living room that have this coating, which now has played for 4,5 years.
These speakers are by the way built in a special manner for testing different coatings and has detachable stators held in place with magnet strips. I have been told that this arrangement is patentable but I can take some photos if anyone is interested.
Hi JonasKarud,
Please take a few pictures to show us how the arrangement looks like. I'm very interested to see.
Wachara
Please take a few pictures to show us how the arrangement looks like. I'm very interested to see.
Wachara
Surface treatment:
I got a couple of emails about this; I admit that I used a large commercial unit, since I had one at work. How to do this at home?
Here's a relatively inexpensive way to do it. First, browse through this site:
http://www.electrotechnicproduct.com/
They have a handheld corona treater for about $450 (BD-20, but similar units can be found for about $350). But wait! They also have a pinhole detector, the BD-10 for $176. It's pretty easy to rig up the coat-hanger electrode of the '20 and fit it onto the '10- the electrodes are replaceable and slip in and out pretty easily.
If you're a true cheapskate, it would be a nice afternoon project to rig up a Tesla coil of your own- I might be tempted to do it out of some of the critical parts that Electro Technic sells.
Otherwise, I'd find two or three other people who want to play with ESLs and split the cost.
I got a couple of emails about this; I admit that I used a large commercial unit, since I had one at work. How to do this at home?
Here's a relatively inexpensive way to do it. First, browse through this site:
http://www.electrotechnicproduct.com/
They have a handheld corona treater for about $450 (BD-20, but similar units can be found for about $350). But wait! They also have a pinhole detector, the BD-10 for $176. It's pretty easy to rig up the coat-hanger electrode of the '20 and fit it onto the '10- the electrodes are replaceable and slip in and out pretty easily.
If you're a true cheapskate, it would be a nice afternoon project to rig up a Tesla coil of your own- I might be tempted to do it out of some of the critical parts that Electro Technic sells.
Otherwise, I'd find two or three other people who want to play with ESLs and split the cost.
Photos
Here's link to some photos and comments on my Esl speakers.
If you have any ideas on improving these speakers, please let me know.
http://picasaweb.google.com/jkarud
Here's link to some photos and comments on my Esl speakers.
If you have any ideas on improving these speakers, please let me know.
http://picasaweb.google.com/jkarud
Hi Jonas,
great work!
How does it sound?
What distance plate to membrane
have you found out to be good at what voltages?
Please, tell us all about it!
Thanks,
Frank
great work!
How does it sound?
What distance plate to membrane
have you found out to be good at what voltages?
Please, tell us all about it!
Thanks,
Frank
There is some very innovative stuff in there! Or at least stuff I had not seen before. I like the tension adjuster idea - very cool. The magnetic fixation of the stator is also very clever indeed. I'm not convinced of the drive signal derived polarizing voltage though, or did you find a way to achieve constant charge?
Did you find any disadvantage of hanging the stators on the film?
Did you find any disadvantage of hanging the stators on the film?
The stator/ film distance is 2.5 mm. The input via 2 Mohm to the 10-step voltage doubler is restricted by a 230 volt varistor:
https://www1.elfa.se/elfa~eu_en/b2b/catalogstart.do?tab=catalog
I think that one very important component is the high voltage rectifier diodes on ladder output, preventing the charge from going back from speaker to ladder at very low level listening.
When you start up the music, it takes 5-6 seconds before the speaker is charged up and it seem to keep this charge as long as you play some music at low to normal levels. When music is turned off, the charge disappears in about 10 to 30 minutes, this seem to depend on humidity.
At least I'm very happy with with this arrangement and will never ever connect my future speaker to the mains!
The sound, yes, hard to tell, maybe a bit like bigger Audiostatics.
The stators do not wrinkle the 12 my mylar membran thanks to the tape
on membrane sides and the resting pillars in form of small plexi blocks.
One funny thing is the dividing of the membrane into four fields, quite similar to Martin L model CLX. I made my speaker many years before ML!
https://www1.elfa.se/elfa~eu_en/b2b/catalogstart.do?tab=catalog
I think that one very important component is the high voltage rectifier diodes on ladder output, preventing the charge from going back from speaker to ladder at very low level listening.
When you start up the music, it takes 5-6 seconds before the speaker is charged up and it seem to keep this charge as long as you play some music at low to normal levels. When music is turned off, the charge disappears in about 10 to 30 minutes, this seem to depend on humidity.
At least I'm very happy with with this arrangement and will never ever connect my future speaker to the mains!
The sound, yes, hard to tell, maybe a bit like bigger Audiostatics.
The stators do not wrinkle the 12 my mylar membran thanks to the tape
on membrane sides and the resting pillars in form of small plexi blocks.
One funny thing is the dividing of the membrane into four fields, quite similar to Martin L model CLX. I made my speaker many years before ML!