Be careful with Final. I had a rather poor experience with them while trying to buy a set of speakers from them recently. I can't speak to their product, only how they conduct themselves. I was ready to spend $7000US or more with them and had such a bad experience that I bought a set of Acoustats instead. Like I said, be careful with Final.
How much of this is first hand info? How much is wishful thinking, assuming or guessing?
Stators like the ones in the original Quad ESL in 1957.
I don't think there is any "wishful thinking", because WrineX already made a lot of ESL. I can't imagine the "wishful thinking" phrase is right in this context.
I remember reading advertisement of Final in which they mentioned PMMA stators This material is also known as acrylic glass, brandname plexiglass. I also remember reading about that printjng proces . One can ask the question what difference it makes in performance. My gut feeling is that plastic stators should have advantages compared to metal ones. Like having better internal damping. Measurements could prove it. Unfortunately almost none of the commercial producers provide any measurements at all. Sometimes better magazines like stereophile do perform measurements but as far as I know they never neasured or tested Final let alone the newer models.
I was referring to the info about production methods in Final products, not his DIY work.
He made a lot of planars, not ESL's. That is at least what his video's show.
Sorry, if I was ambiguous! The "wishful" word is inappropriate IMO, because it corresponds a kind of difficulty about his targets (perhaps my english isn't too well).
OK, a lot of planars and some ESL (inverted mode, normal ones and stacked)... see his videos.
"The stators used to be made of metal, but Final uses PMMA plastic stators."
https://hifi.nl/artikel/29394/Review-Final-15-Final-Innovation.html
It is kind of 'funny' that the reviewer states that these Final speakers, costing over 12.000 euro, have good price/quality ratio.
It is kind of 'funny' that the
Fixed that for you.
Haha, yeah its nothing only 12k...
Well directly from the owner himself.
or maybe they gave it a slight curve. (not sure if that is the case i did not ask and cant remember they where)
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Oh yeah i somehow thought they where a form of PCB ? but not the glass fibre later stuff ? or did they also had a form of plastic and made it conductive them self. anyhow this is a bit different i think since the acrylic is also the exterior of the speakers.
You're mixing up the original ESL and the ESL-63.
But hey, this thread was supposed to be about coating, so let's get back to that initial subject.
In pure curiosity filling testing box with generic freon R12 raised breakdown volage of an isolating standoff from 40 kV to more than a hundred.
As you know, because of a higher g/mol value. as was used by Dayton Wright with SF6 gas in his electrostatic speakers
Yes, you can reduce the arc risk, increase the voltage, but you introduces another challenge.
As the density of SF6 gas and R12 is different from the density of air (that's why it can withstand higher voltage, has a higher isolation value).
The g/mol value of SF6 is 146 g/mol, R12 is 120 g/mol, where air is 29 g/mol (at sea level at 20 degrees Celsius)
That also means frequency travel velocity is different, expansion rate with temperature and moist is different etc.
And the main question is, why?
I can easily listen at 90 dB peak levels (Uni-T UT353) at listening position with my Quad ESL Plus 63 set.
Listening position is 5 meters from the speakers in my 12x8x2,5 meter living room, currently 60% humidity @ 25 degrees Celsius.
More than loud enough for me. no gas needed.
Yes, you can reduce the arc risk, increase the voltage, but you introduces another challenge.
As the density of SF6 gas and R12 is different from the density of air (that's why it can withstand higher voltage, has a higher isolation value).
The g/mol value of SF6 is 146 g/mol, R12 is 120 g/mol, where air is 29 g/mol (at sea level at 20 degrees Celsius)
That also means frequency travel velocity is different, expansion rate with temperature and moist is different etc.
And the main question is, why?
I can easily listen at 90 dB peak levels (Uni-T UT353) at listening position with my Quad ESL Plus 63 set.
Listening position is 5 meters from the speakers in my 12x8x2,5 meter living room, currently 60% humidity @ 25 degrees Celsius.
More than loud enough for me. no gas needed.
It's an occasional test. Both SF6 and R12 are negative gases - it's really hard to develop a discharge not mentioning arc in a volume filled with it. In real life SF6 develops all kind of polymers which are really nasty and means to absorb such thingies are usually present at installations.
To make it simple - one may replace SF6 which is PITA to get with rather simple substitute. For real...
Well, I would happily pay euro the 60.00 for bottle of your secret PEDOT-PSS coating with some instructions of how to apply it ...
Soon I will start a project including refurbishing two pairs of ELS63 stored for twenty years.
Just for fun i asked chatGPT for a coating formula for my esl63 using pedot pss. I got the following answer.
Materials:
1. PEDOT😛SS dispersion (e.g., Clevios PH1000 or Heraeus conductive grade).
2. Dimethyl sulfoxide (DMSO) or ethylene glycol (EG) (conductivity enhancer).
3. Deionized (DI) water (for dilution and thinning).
4. Surfactant (optional, e.g., Triton X-100 for better wetting).
5. Isopropyl alcohol (IPA) (for cleaning Mylar).
6. Foam brush (for manual application).
Equipment:
1. Precision scale.
2. Clean glassware (for mixing the solution).
3. Surface resistivity meter (for testing the coating).
Recipe:
1. Base Solution:
• Start with 10 mL of PEDOT😛SS dispersion.
• Add 5 vol% DMSO or EG to improve conductivity and mix thoroughly for 5 minutes.
2. Dilution:
• Dilute the mixture with 10–20 mL of DI water, depending on the desired thickness and brushability. Thinner solutions are easier to spread with a foam brush but may require multiple layers.
3. Surfactant (Optional):
• Add 0.1 wt% Triton X-100 to improve wetting on Mylar. This helps the solution spread evenly and minimizes streaks.
Procedure:
1. Prepare Mylar Surface:
• Clean the Mylar with IPA to remove any dust, oils, or contaminants.
• Allow it to air-dry or use a lint-free cloth to dry it completely.
2. Apply Coating:
• Dip the foam brush into the prepared PEDOT😛SS solution.
• Apply a thin, even layer across the Mylar in smooth, continuous strokes. Avoid overloading the brush to minimize pooling and streaks.
• Let the coating air-dry naturally in a dust-free environment. This may take 30–60 minutes depending on humidity and airflow.
3. Test Resistivity:
• Once dry, measure the surface resistivity with a resistivity meter.
• If resistivity is too low (<10^7 \, \Omega/\text{sq}), dilute the solution further with DI water and reapply.
• If resistivity is too high (>10^9 \, \Omega/\text{sq}), increase the DMSO/EG content slightly (up to 10 vol%) and apply a new coat.
4. Optional Additional Coats:
• For fine-tuning, you can apply additional thin coats. Allow each layer to dry before applying the next.
Key Considerations:
• Work in a clean, dust-free area to avoid imperfections in the coating.
• Use consistent pressure and motion with the foam brush to ensure uniform thickness.
• Let the coating cure for at least 24 hours in a stable environment before assembling the speaker.
This method avoids the need for heating while still providing a functional coating within the specified resistivity range. Adjust the DMSO/EG and dilution as needed to meet your requirements.
Materials:
1. PEDOT😛SS dispersion (e.g., Clevios PH1000 or Heraeus conductive grade).
2. Dimethyl sulfoxide (DMSO) or ethylene glycol (EG) (conductivity enhancer).
3. Deionized (DI) water (for dilution and thinning).
4. Surfactant (optional, e.g., Triton X-100 for better wetting).
5. Isopropyl alcohol (IPA) (for cleaning Mylar).
6. Foam brush (for manual application).
Equipment:
1. Precision scale.
2. Clean glassware (for mixing the solution).
3. Surface resistivity meter (for testing the coating).
Recipe:
1. Base Solution:
• Start with 10 mL of PEDOT😛SS dispersion.
• Add 5 vol% DMSO or EG to improve conductivity and mix thoroughly for 5 minutes.
2. Dilution:
• Dilute the mixture with 10–20 mL of DI water, depending on the desired thickness and brushability. Thinner solutions are easier to spread with a foam brush but may require multiple layers.
3. Surfactant (Optional):
• Add 0.1 wt% Triton X-100 to improve wetting on Mylar. This helps the solution spread evenly and minimizes streaks.
Procedure:
1. Prepare Mylar Surface:
• Clean the Mylar with IPA to remove any dust, oils, or contaminants.
• Allow it to air-dry or use a lint-free cloth to dry it completely.
2. Apply Coating:
• Dip the foam brush into the prepared PEDOT😛SS solution.
• Apply a thin, even layer across the Mylar in smooth, continuous strokes. Avoid overloading the brush to minimize pooling and streaks.
• Let the coating air-dry naturally in a dust-free environment. This may take 30–60 minutes depending on humidity and airflow.
3. Test Resistivity:
• Once dry, measure the surface resistivity with a resistivity meter.
• If resistivity is too low (<10^7 \, \Omega/\text{sq}), dilute the solution further with DI water and reapply.
• If resistivity is too high (>10^9 \, \Omega/\text{sq}), increase the DMSO/EG content slightly (up to 10 vol%) and apply a new coat.
4. Optional Additional Coats:
• For fine-tuning, you can apply additional thin coats. Allow each layer to dry before applying the next.
Key Considerations:
• Work in a clean, dust-free area to avoid imperfections in the coating.
• Use consistent pressure and motion with the foam brush to ensure uniform thickness.
• Let the coating cure for at least 24 hours in a stable environment before assembling the speaker.
This method avoids the need for heating while still providing a functional coating within the specified resistivity range. Adjust the DMSO/EG and dilution as needed to meet your requirements.