Electrostatic speakers?

[Eytsch]

I don't know who came up with the copper foil charge ring idea but it's a good one, and it's been used by DIY builders for many years, including all of my builds since 2008.

Vapor-deposited indium-tin oxide may be the current state of the art in diaphragm coatings, but that process isn't feasible for us DIY builders, so we have to make do with whatever we can find.

Historically, DIY coatings have included rubbed-in powdered graphite, or graphite slurries (messy and difficult to get uniform resistance), carbon-black mixed with a paint binder (very reliable but opaque), wiped-on dish soap (works well but attracts dust), metalized Mylar (way too conductive, prone to arcing), and mixtures containing anionic salts. Of these coatings, only carbon-black paint has proven longevity.

The DIY community now uses anti-static ESD products almost exclusively (Licron Crystal, Staticide, Stat-Clear). These coatings have close to ideal resistance (E7-E9 Ohms) but no one really knows how long they will last.

I've used LIcron Crystal for about 12 years, but I've given away the older panels and I don't know how many are still playing. The oldest wire panels I have kept up with were built in 2015 and the owner says they still play fine. My personal speakers with the Licron Crystal coating are about 5 years old now and I haven't noticed any loss in output. Time will tell....

The Licron is working well so far, but it's not cheap, and I would love to develop a cheap, easy, clear coating that lasts forever. This would be the holy grail.

To the couple of DIY builders out there who claim to have such a coating, and are selling their closely guarded secret sauce, I say this: Yes of course, you have every right to guard your secret for sale and profit, but you probably aren't making a lot of money on it since the ESD products showed up (there aren't that many of us to buy it from you), so why not share your formula with those who would appreciate your benevolence?

The speakers I build were largely enabled by other builders sharing their knowledge with me over many years. So if I had a holy grail coating, I would pay it forward by freely sharing it with the DIY community.

The more you post comments like this the closer I get to acquiring another DIY hobby. Mercy please. I still have 2 tube guitar amp builds to complete.

 

[Jazzman53]

The more you post comments like this the closer I get to acquiring another DIY hobby. Mercy please. I still have 2 tube guitar amp builds to complete.

It's a psychosis and I'm an enabler so go for it: https://jazzman-esl-page.blogspot.com

 

[Jaxjax]

It's a psychosis and I'm an enabler so go for it: https://jazzman-esl-page.blogspot.com

You still run the Ripole subs with em .?

 

[Jazzman53]

You still run the Ripole subs with em .?

Absolutely! . The Ripol's compliment the OB mid-bass drivers perfectly. The combo is non-boomy and clean and tight like I had never experienced before.

 

[misterdog]

Contributing to the claimed (and ime genuinely improved) longevity of SoundLab's PX panels is the very high structural rigidity of the plastic lattice that the stators are attached to, which prevents this type of failure mode. Earlier generation SoundLab panels were not as rigid and there were stator insulation breakdowns that corresponded with rough handling in shipment. The "PX" generation of panels was designed for commercial use in permanant installations like movie theaters, so they had to be competitive with conventional speakers in ruggedness and reliability.

As posted earlier, I love the sound of marketing speak.

Me, Me, Me, mine are the best.

Peter Walker at Quad Acoustics was designing electrostatics some 20/30 years before Soundlab jumped on board.

The Quad 63 Pro series were also designed for 'rough handling' in studios and such.

 

[Duke]

As posted earlier, I love the sound of marketing speak.

Me, Me, Me, mine are the best.

Peter Walker at Quad Acoustics was designing electrostatics some 20/30 years before Soundlab jumped on board.

The Quad 63 Pro series were also designed for 'rough handling' in studios and such.

I'd be more than happy to have a substantive conversation with you, as apparently you have a great deal of experience with Quads. Maybe you consider me to be "the enemy" because of my association with a "rival" brand. I've owned four pairs of Quads, three of them purchased AFTER I became a SoundLab dealer. If it was practical for me to do so, I'd be a dealer for BOTH brands.

 

[Blumlein 88]

As posted earlier, I love the sound of marketing speak.

Me, Me, Me, mine are the best.

Peter Walker at Quad Acoustics was designing electrostatics some 20/30 years before Soundlab jumped on board.

The Quad 63 Pro series were also designed for 'rough handling' in studios and such.

I owned Quads both 57 and 63. I consider the ESL-63 to be the best commercial design for an electrostat ever with the delayed concentric rings. I had hoped someone would take up the mantle with more concentric rings and larger panels or vertically segmented tall panels with delays between the segments for a proper line source. Jazzman has done something like that with his speakers. An all out design incorporating DSP to feed segments could be something very close to a true line source or point source.

What the Soundlabs, which I have also owned, do is give a bigger sound from the larger panel, and the ability to take in more power (up to 1000 watts). I'm not sure how much the curving helps, but it seems to help some. The Sounldabs are essentially a curved Acoustat (which I owned as well). Some of which also could use up to 1000 watts and were large enough to help.

With the dearth of ESLs available I wouldn't disparage any approach very much unless it is truly dreadful.

 

[DavidEdwinAston]

Can I ask you guys if you think that the current "top", Quad's have added anything to their electrostatic history?

 

[misterdog]

No.

Apart from the cosmetic makeover, the addition of the rear brace, and the additional anti topple ballast weight they are identical to my 989's.

Quad did take an 8 panel ESL to Munich a few years ago, but it was a non working prototype, I have heard nothing of it since.

 

[dlaloum]

As posted earlier, I love the sound of marketing speak.

Me, Me, Me, mine are the best.

Peter Walker at Quad Acoustics was designing electrostatics some 20/30 years before Soundlab jumped on board.

The Quad 63 Pro series were also designed for 'rough handling' in studios and such.

Although from memory... the pro series were USA only - and the BBC (and other European recording studios) used the "standard" 63's...

So I have a gut feeling that the "pro" series, was more marketing, focused on an american need for "trucks"...

 

[Newman]

"There ain't no substitute for coooobs"

 

[Blumlein 88]

Although from memory... the pro series were USA only - and the BBC (and other European recording studios) used the "standard" 63's...

So I have a gut feeling that the "pro" series, was more marketing, focused on an american need for "trucks"...

I think the pro series were first made for European recording studios (Philips) though only sold in the USA as the Quad ESL-63 USA monitor series. They had a steel frame as I recall, not marketing. There were real differences.

 

[Duke]

I think the pro series were first made for European recording studios (Philips) though only sold in the USA as the Quad ESL-63 USA monitor series. They had a steel frame as I recall, not marketing. There were real differences.

My first pair of Quads were "USA Monitors". I was aware that they incorporated improvements over the original ESL-63 but don't remember the specifics.

 

[dlaloum]

I think the pro series were first made for European recording studios (Philips) though only sold in the USA as the Quad ESL-63 USA monitor series. They had a steel frame as I recall, not marketing. There were real differences.

Yes, I believe they had either a steel frame or steel reinforcing... although the panels and electronics were the same.

Will do a search to find out their history - I don't remember them being available in the UK/Europe/Asia (definitely not in Australia - I used to sell them)

 

[dlaloum]

Found the reference:

The speaker's structural rigidity was increased for the launch of the ESL-63 USA Monitor in 1988. This evolved from a special "pro" version used by Philips' European recording division for location recording. Quad replaced the '63's aluminum frame with steel, and put handles on the sides and rubber kick pleats at the base. Philips was delighted, and soon other studios requested the "pro" version. Quad decided that the improved structural rigidity made it the best version for export, even though it increased the speaker's weight by 30%.

https://www.stereophile.com/content...static-loudspeaker-page-2#ieG86WQOEuLfT8Rh.99

So yeah - Limited, "by request only" release in Europe... and then the USA Monitor was the official version...

Perhaps in the later periods, the USA Monitor was also available to other "export" regions - I switched from audio to IT by the mid 80's, so I may have lost track of developments!

I have seen a couple of ESL63 "Pro" models in Australia, but it is hard to tell whether they were later personal/direct imports, or whether they were officially imported and sold here... (they certainly were not available through official channels circa 84/85 when I was involved in/with the "official channels" )

 

[AdVis]

When I worked at PolyGram (around 1975ish) they had a "special version" of the ESL57 (silver grille). I never really figured out what was special apart from the different grille, but it was quite ubiquitous especially for classical music (Polyhymnia et al), it was also used in quality control and mastering, along with JBL 4315's.

I'm running a pair of (ordinary ) ESL57's complemented by two DIY 2x12" Ripole subwoofers and they manage to amaze me every time again.

 

[misterdog]

Found the reference:

The speaker's structural rigidity was increased for the launch of the ESL-63 USA Monitor in 1988. This evolved from a special "pro" version used by Philips' European recording division for location recording. Quad replaced the '63's aluminum frame with steel, and put handles on the sides and rubber kick pleats at the base. Philips was delighted, and soon other studios requested the "pro" version. Quad decided that the improved structural rigidity made it the best version for export, even though it increased the speaker's weight by 30%.

https://www.stereophile.com/content...static-loudspeaker-page-2#ieG86WQOEuLfT8Rh.99

So yeah - Limited, "by request only" release in Europe... and then the USA Monitor was the official version...

Perhaps in the later periods, the USA Monitor was also available to other "export" regions - I switched from audio to IT by the mid 80's, so I may have lost track of developments!

I have seen a couple of ESL63 "Pro" models in Australia, but it is hard to tell whether they were later personal/direct imports, or whether they were officially imported and sold here... (they certainly were not available through official channels circa 84/85 when I was involved in/with the "official channels" )

To me the actual frame rigidity is less important than the attachment of the panels to the frame.

Here is the actual aluminium angle (not more rigid T section) that my 989's panels were attached to, 1200mm. long and 1.2mm thick section, you can see where each of the 6 panels were attached. The soft open cell black foam is non sense to me.

Here is the deflection of this aluminium L section with a carboard box and 9 DVD's.

That L section is only held at the top and bottom frame plates.

With the weight of that box and DVD's the aluminium deflects by 4 mm in the centre (less than the weight of 3 of the panels).

The membrane in each panel only has an excursion of around 1mm when playing music, this is (was) the problem to me with the lack of dynamics.

My cat litter filled, steel box section frames, with the panels attached to a 30 x 10 x 2 mm aluminium angle, attached to the frames along their full length solves this problem to me.

When I first played them after the rebuild I feared I had 'broken' them, the reality was that there was so much more detail and dynamics that I had to reduce the cartridge loading on my phono stage by 20 Ohm.

 

[Ron Texas]

Electrostatics are pricey. They don't measure well, but maybe they run under a different set of rules than conventional loudspeakers.

 

[misterdog]

Electrostatics are pricey. They don't measure well, but maybe they run under a different set of rules than conventional loudspeakers.

No 'box' sound, no crossover distortion, to start with.

They measure enormously though, mine are the size of my entrance door.

When you say pricey, what are you comparing to ?

https://www.hificorner.co.uk/product/meridian-dsp-8000-xe-digital-active-loudspeakers/?attribute_pa_finish=glossblack&gad_source=1&gclid=Cj0KCQjw8pKxBhD_ARIsAPrG45kVoy4yrTWxFOLnJlF-TuupDZ6WN7OfW_ZPoH5UQGRcx0v3c66ER-saAv2oEALw_wcB

I think my Quads were a bargain...

 

[Ron Texas]

@misterdog there good conventional speakers which don't cost a lot. There are no good electrostatics which don't cost a lot. It proves nothing to show that some conventional speakers are expensive. You are trying to pass off an exception as the rule.

A properly designed enclosure has no box sound.