Electrostatic speakers?

[Arindal]

There are some superb Mercury, Philips and Decca recordings from early days.
I found Deutche Grammofon recordings unrealistic, though there are some great performances.

You have named 3 out of 4 record labels (Mercury is the exception) which I consider to show the least consistency, i.e. vast variety of different recording styles, philosophies and results over different decades, countries, conductors and recording teams. It is impossible to comment on that.

he was authorised to send some clips from the recording, both from a multi miked mix and from an old school simply miked setup.
The old school sounded markedly better in instrumental timbre to me but was noisier.

You do not specify the recording, so I cannot comment. But particularly with Baroque oratorios, there is always a reason to use spot microphones, if one wants to retain a minimum of balance between the groups of instruments and intelligibility of the choir. What you describe as ´old school´, was probably the pure signal from the main mic which is meant to have spot microphones added, so from what you describe I would assume a runtime stereophony setup was used and it inherently contains dominant indirect sound, i.e. ´drowns in reverb´.

I have been doing a brief project with the late T. Nishimura, who previously had made some experiments with multi-mic recordings vs. one-points of one and the same performance, with the main mics being placed differently. These are rare examples of both versions being publicly available and allowing a comparison. I have been discussing things with him, and the 2-channel one-points don't stand a chance (the 5-channel are actually much better and closer to what you might imagine).

Nowadays (for like 20 years) the timbral qualities of all instruments and the venue alike, can be retained in a multi-mic mixdown, if it is done properly. There are several classical record labels having brought this to perfection. Can give recommendations, if you are interested in a specific work. Some even managed to achieve this ´long reverb decay´ impression without sacrificing the music.

 

[Keith_W]

Challenge accepted. I zoomed so that it's the same time scale as yours. Speaker is a 4 way system with subwoofers, dynamic driver woofers, and horns for mids and treble.

 

[Newman]

@Keith_W can you link to the ‘challenge’ and the comparative graph, please? I’m lost.

 

[Keith_W]

He deleted his post after I posted my reply. It went something like "I took an impulse response of my ESL's and I challenge owners of dynamic drivers to post your impulse response".

 

[Newman]

He deleted his post after I posted my reply. It went something like "I took an impulse response of my ESL's and I challenge owners of dynamic drivers to post your impulse response".

I see. What is your personal view of the two impulse responses compared?

 

[Keith_W]

I see. What is your personal view of the two impulse responses compared?

The "head" of the two impulse responses looked the same, but the tails are different. Mine has more room reflections than his. I know from his previous posts that he believes in narrow directivity and has treated his room to reduce reflections, so it is not surprising that my wider radiating speakers with no room treatment should have more room reflections. He did not explicitly state the point of his challenge, but I think he wanted to show that there was less ringing with ESL's or maybe more time coherence, I don't know. If he wanted to look at ringing, he should have asked for a step response, but he didn't.

 

[Pmerendino]

SoundLab electrostats offer an arguably well thought-out combination of attributes. Disclaimer - I'm a dealer. And in sighted listening I think they sound good. So please everyone, discount my opinion accordingly.

SoundLabs use a segmented horizontal curve which gives a relatively wide and uniform radiation pattern, the horizontal angle between the panels being small enough that there is no "picket fence" effect at audible frequencies.

Each vertical facet is divided into "cells" which vary in size such that their drum-head resonances are spread out in frequency in a way that helps to offset dipole cancellation. I've measured SoundLabs in-room and they have low-end extension down into the low 20's. Of course their large size helps with that.

Here is a photo of the back of a SoundLab panel. You can see that the horizontally-segmented curve is arranged to converge to the rear and diverge forward. You can also see the gradation in the vertical size of the individual cells. The entire diaphragm is a single membrane (receiving a full-range signal), and is clamped by the frame, effectively dividing it into the many individual cells:
.

View attachment 462716

(The small vertical lines you see in the above photo are the insulated stator wires. There is also a hard plastic "waffle" in each cell for structural rigidity. The large rectangles - formed by the 7 horizontal divisions and the multiple vertical divisions which grow larger towards the top and bottom - are what I'm referring to as "cells".)

SoundLabs seek to approximate a line source, and the recommendation is that their height be a little bit less than the height of the room, such that the floor and ceiling reflections effectively extend the listening distance to which they approximate line source behavior.

SoundLab offers two radiation pattern widths: 90 degrees, and 45 degrees. The photo above is of a 45-degree panel. I started out with the 90 degree panels 25 years ago, as that was the only choice in the full-sized models. Comparing the two makes for a pretty close to "apples to apples" comparison of the different radiation pattern widths, though of course the line-source-approximating, dipole SoundLabs are not representative of different radiation pattern widths in "conventional" speakers. The pattern of course widens to the familiar dipole figure-8 at frequencies too low for the specific panel geometry to control the pattern width.

Roger West of SoundLab has an online white paper describing their technology, if anyone is interested. He is not particularly focused on the fact that his approach results in relatively little spectral discrepancy between the direct sound and the reflection field, but imo that is among their best attributes, and largely distinguishes them from their competition.

Yes, Soundlab's do sound nice, however, they can sound Much better. the ripple voltage on the bias supplies interacts with the voltage on the stators causing distortion. I am a 45 Year SL Owner. The High Voltage filter I built minimizes these distortions. The difference with this upgrade is really amazing. I call it the Leage Changing Modification - or LCM for short. This is a real and very curable problem with all SL speakers using the Switching Power Supplies since mid 1980's. The ripple voltage swings around 30 to 50 volts p-p at around 15KVDC. The voltage on the stator's ranges from Zero to around 100 Volts depending on the volume. This ripple voltage - even at a high switching frequencies causes audible distortion. Comments are welcome and encouraged.

 

[Pmerendino]

SoundLab electrostats offer an arguably well thought-out combination of attributes. Disclaimer - I'm a dealer. And in sighted listening I think they sound good. So please everyone, discount my opinion accordingly.

SoundLabs use a segmented horizontal curve which gives a relatively wide and uniform radiation pattern, the horizontal angle between the panels being small enough that there is no "picket fence" effect at audible frequencies.

Each vertical facet is divided into "cells" which vary in size such that their drum-head resonances are spread out in frequency in a way that helps to offset dipole cancellation. I've measured SoundLabs in-room and they have low-end extension down into the low 20's. Of course their large size helps with that.

Here is a photo of the back of a SoundLab panel. You can see that the horizontally-segmented curve is arranged to converge to the rear and diverge forward. You can also see the gradation in the vertical size of the individual cells. The entire diaphragm is a single membrane (receiving a full-range signal), and is clamped by the frame, effectively dividing it into the many individual cells:
.

View attachment 462716

(The small vertical lines you see in the above photo are the insulated stator wires. There is also a hard plastic "waffle" in each cell for structural rigidity. The large rectangles - formed by the 7 horizontal divisions and the multiple vertical divisions which grow larger towards the top and bottom - are what I'm referring to as "cells".)

SoundLabs seek to approximate a line source, and the recommendation is that their height be a little bit less than the height of the room, such that the floor and ceiling reflections effectively extend the listening distance to which they approximate line source behavior.

SoundLab offers two radiation pattern widths: 90 degrees, and 45 degrees. The photo above is of a 45-degree panel. I started out with the 90 degree panels 25 years ago, as that was the only choice in the full-sized models. Comparing the two makes for a pretty close to "apples to apples" comparison of the different radiation pattern widths, though of course the line-source-approximating, dipole SoundLabs are not representative of different radiation pattern widths in "conventional" speakers. The pattern of course widens to the familiar dipole figure-8 at frequencies too low for the specific panel geometry to control the pattern width.

Roger West of SoundLab has an online white paper describing their technology, if anyone is interested. He is not particularly focused on the fact that his approach results in relatively little spectral discrepancy between the direct sound and the reflection field, but imo that is among their best attributes, and largely distinguishes them from their competition.

Here is a very good visual of a 10KHZ test tone showing the interacting og the Bias Ripple Voltage distorting the signal being presented to the Diaphragm. This is very audible - noteably (bad pun) when listening and comparing to a pair of SL's with the LCM modification. The speakers essentially dissapear. The Violet wave is the test signal, the Yellow is the signal on the Diaphragm. This is what you hear when the air moves precisely with the Diaphragm. All SL Owners need to experience this.

 

[Pmerendino]

Several of us have them. I have some Soundlabs. I've owned several ESL's. I suppose the big thing is we need to get some to Amir to measure on the Klippel device. Then discuss the results. Ray Dunzl has some Martin Logans and has posted many aspects of measurements using REW.

Hello, I placed some information about Soundlab Speakers on this forum you may be interested in...

Post in thread 'Electrostatic speakers?'

Jul 11, 2025

Just from theoretical point I would prefer the Martin Logan solution with arc-shaped diaphragm and vertically segmented suspension to prevent long-wavelength resonances.

SoundLab electrostats offer an arguably well thought-out combination of attributes. Disclaimer - I'm a dealer. And in sighted listening I think they sound good. So please everyone, discount my opinion accordingly.

SoundLabs use a segmented horizontal curve which gives a relatively wide and uniform radiation pattern, the horizontal angle between the panels being small enough that there is no "picket fence"...

• Duke

• 

Thoughts?

 

[Pmerendino]

Several of us have them. I have some Soundlabs. I've owned several ESL's. I suppose the big thing is we need to get some to Amir to measure on the Klippel device. Then discuss the results. Ray Dunzl has some Martin Logans and has posted many aspects of measurements using REW.

Several of us have them. I have some Soundlabs. I've owned several ESL's. I suppose the big thing is we need to get some to Amir to measure on the Klippel device. Then discuss the results. Ray Dunzl has some Martin Logans and has posted many aspects of measurements using REW.

Hello, I did request Amir to review my Ripple findings with Soundlab Speakers. He was of the opinion there would not be any interest. Perhaps if other members requested there may be a reconsideration?

 

[goryu]

I have Acoustat 6600. I would certainly be interested in some measurements of large, dipole electrostatic speakers.