Quad Electrostatic models.

[martin clark]

Yup. read it before and it concurs with my thoughts on the number of these panels

Sorry - I might not have made clear the advantage of size - and it's nothing to do with the panel used.



What rolls-off the low-end response of a dipole is the distance from acoustic centre of the front, around the edges, to the acoustic centre of the back. Increase that - however crudely - and the bass extension increases for no other change. It's true - also exactly why sealed boxes are often called 'infinite baffle'.

If you took a ESL63, cut a piece of stiff board the same face area, sliced it down the centre and closely-located each half either side of the 63- you get, in theory - nearly another octave of bass extension (except now the short route is over the top. So try addressing that, too.)

So 6-panel Quads do gain bass extension - just from being 50% more area by being taller - but, not as much as if they were also, wider. But that extra width could be just a baffle- it abs does.not need to be , more electrostat area. I must get around to trying this some day, in a bigger room - it's long been on the to-do list for a decade.

Acoustics, eh... but this is why 'stacked ESl57s' have the reputation they do. The bass end of teh sepaker panel itself doen't go any lower, but working half as hard/ so sounding less-tubby - it's actually the 100% face area increase, that lends useful in-room bass response extension.

 

[camverton]

Sorry - I might not have made clear the advantage of size - and it's nothing to do with the panel used.



What rolls-off the low-end response of a dipole is the distance from acoustic centre of the front, around the edges, to the acoustic centre of the back. Increase that - however crudely - and the bass extension increases for no other change. It's true - also exactly why sealed boxes are often called 'infinite baffle'.

If you took a ESL63, cut a piece of stiff board the same face area, sliced it down the centre and closely-located each half either side of the 63- you get, in theory - nearly another octave of bass extension (except now the short route is over the top. So try addressing that, too.)

So 6-panel Quads do gain bass extension - just from being 50% more area by being taller - but, not as much as if they were also, wider. But that extra width could be just a baffle- it abs does.not need to be , more electrostat area. I must get around to trying this some day, in a bigger room - it's long been on the to-do list for a decade.

Acoustics, eh... but this is why 'stacked ESl57s' have the reputation they do. The bass end of teh sepaker panel itself doen't go any lower, but working half as hard/ so sounding less-tubby - it's the 100% area increase, that lends useful in-room bass response extension.

All very true. The only snag I can think of about increasing the “baffle” size is that one might lose that wonderful sense of music being played in a space, which might, I wonder, be one of the reasons I prefer the four panel design over the six panel. Careful placement can ameliorate a lot of bass issue with dipoles. The trick, I’ve found, is finding a balance between best bass response and the best illusion of having real musicians playing in front of me.

 

[martin clark]

: D

Actually - increasing baffle area - theoretically -should not alter such perception. maybe even enhance it.

Which is why its an experiment I'll get to, someday.

 

[al2002]

The effective baffle size difference between the 4 and 6 panel ESLs is a small fraction of a wavelength. The cancellation of front and back waves off the sides is the same in both because the path length difference is the same. The in-room LF response of either ESL will pretty much be determined by placement and room acoustics.

See: https://www.linkwitzlab.com/models.htm

And: https://www.linkwitzlab.com/frontiers_4.htm

 

[Mike Reed]

Correct.

I've only got experience of 57s and my current 6 panel 2905s in my house but friends have stacked 57s, 989s and 2812s. I simply don't believe in adding sub-woofers, nor have ever done, as every speaker I've had (and mainly larger floor-standing m/coils) has had the required fr. extension. Why buy speakers and then add separate boxes to redress the inadequacies of the pair you've bought? Simplistic, I know, but to me it's logical thought.

I think we must be conversing at cross purposes here as the extra 2 panels in each ESL does both improve loudness and frequency extension according to all reports. although by not much. As in most hifi and Tesco, every little helps !

Maybe I've got a conducive room for mine, but there again, I've never had problems with rooms in any house I've had, but they've all been elongated or larger rooms.

 

[camverton]

I've only got experience of 57s and my current 6 panel 2905s in my house but friends have stacked 57s, 989s and 2812s. I simply don't believe in adding sub-woofers, nor have ever done, as every speaker I've had (and mainly larger floor-standing m/coils) has had the required fr. extension. Why buy speakers and then add separate boxes to redress the inadequacies of the pair you've bought? Simplistic, I know, but to me it's logical thought.

I think we must be conversing at cross purposes here as the extra 2 panels in each ESL does both improve loudness and frequency extension according to all reports. although by not much. As in most hifi and Tesco, every little helps !

Maybe I've got a conducive room for mine, but there again, I've never had problems with rooms in any house I've had, but they've all been elongated or larger rooms.

It comes down to taste as much as anything and with subs how well they are integrated. I personally prefer the sound of the smaller Quads which doesn’t mean that someone else might prefer the characteristics of the larger model. That my musical preference is more towards chamber music than large orchestral might, perhaps, have some bearing on this.

Over the past thirty or more years I’ve used subs more often than not And with a variety of different types of speaker. Subs can be very effective when used with stats but they have to be integrated with great care. If crossed over to the stats they could potentially reduce strain on the membranes if a lot of music with loud and low bass is played. If not crossed over as such but played up to the limit of the stats then they can give the missing bottom octave and add a bit of richness where they overlap.

Because a sub is a separate item and can be positioned and adjusted independently they can help deal with inevitable room problems if properly set up. Of course, if you don’t believe in subs then they won’t work for you. Very few speakers will successfully cover the bottom octave so the argument that it is better to buy a pair of better speakers isn’t really valid. Even then, some owners of speakers such as MBL 101s still opt to use subs.

Out of interest Mike, have you measured your hifi/room with REW to see what is happening in the lower frequencies? It would be interesting but if you haven’t and you’re happy with how it sounds it might be best not too. Sometimes it is better to not know when something is amiss; it makes it easier for the brain to compensate!

 

[Mike Reed]

Out of interest Mike, have you measured your hifi/room with REW to see what is happening in the lower frequencies? It would be interesting but if you haven’t and you’re happy with how it sounds it might be best not too. Sometimes it is better to not know when something is amiss; it makes it easier for the brain to compensate!

Ho ho! Being digitally challenged, I've never entertained any of these measuring or diffusing procedures. In fact, Cd came late in hifi life and is as far as I go. If it sounds good, it ain't broke and ergo, doesn't need fixing; that's my Philistine theory !

Interestingly, your choice of chamber music and sub-woofer bass don't quite go hand in hand. Even my current PMC transmission line spkrs do adequate bass for my (admittedly shot) ears, and if they gilded the lily of superb imaging, speed and sound-stage with that wall of sound I also get from the ESLs I'd keep them, as they're so much more room-friendly and my wife doesn't get the rear panel ESL backlash where she sits behind them.

 

[camverton]

Ho ho! Being digitally challenged, I've never entertained any of these measuring or diffusing procedures. In fact, Cd came late in hifi life and is as far as I go. If it sounds good, it ain't broke and ergo, doesn't need fixing; that's my Philistine theory !

Interestingly, your choice of chamber music and sub-woofer bass don't quite go hand in hand. Even my current PMC transmission line spkrs do adequate bass for my (admittedly shot) ears, and if they gilded the lily of superb imaging, speed and sound-stage with that wall of sound I also get from the ESLs I'd keep them, as they're so much more room-friendly and my wife doesn't get the rear panel ESL backlash where she sits behind them.

Philistine theories can be good! Enjoying music is the most important thing, however we achieve it.

Good point about subs and chamber music. I have found, however, that a sub or two does help when a double bass gets involved and there are quite a few composers who explore the depths, including Glass, Part, Crumb, Gubaidulina in their works for smaller forces. I don’t just listen to chamber music; I sometimes stumble into, annd get swept anway by, electronic and drum and bass on my Tidal feed!

I don’t think a sub is an essential addition to a Quad stat so much as completing the picture. Like so much in hifi, one can get to decent, doable sound quite quickly. 95% of the effort is put into moving it to the sublime!

 

[sq225917]

Having spent a lot of time with Mr dogs 989 on stands with two 12" dsp subs in a modestly sized room, I'd say subs are needed if you have any hankering to hear what's really going on in the bottom octaves.

 

[al2002]

I've only got experience of 57s and my current 6 panel 2905s in my house but friends have stacked 57s, 989s and 2812s. I simply don't believe in adding sub-woofers, nor have ever done, as every speaker I've had (and mainly larger floor-standing m/coils) has had the required fr. extension. Why buy speakers and then add separate boxes to redress the inadequacies of the pair you've bought? Simplistic, I know, but to me it's logical thought.

I think we must be conversing at cross purposes here as the extra 2 panels in each ESL does both improve loudness and frequency extension according to all reports. although by not much. As in most hifi and Tesco, every little helps !

Maybe I've got a conducive room for mine, but there again, I've never had problems with rooms in any house I've had, but they've all been elongated or larger rooms.

Later Quad ESLs - 63 on - are designed to emulate a point source, so should not be stacked. The proper way to use multiples is in an L configuration.

I'd like to read these reports of added extension with the larger panels. Can you provide links?

I have only owned the 4 panel ESLs and the difference in bass extention between 4 panels and 8 when used in an L configuration was negligible, room effects were more significant. Room effects being what they are, separate subs , properly placed, can enhance even nominally full range speakers. On large scale orchestral music, subs allow playback at realistic levels with sense of 'ease' that bare Quads cannot manage. Another effect I've noticed with improved bass extension is that recording hall ambiance becomes easier to hear. This is not limited to Quads, of course. As an example, Floyd Toole, of Harmon, uses multiple subs with his Revel Salon 2s.

 

[Mike Reed]

Later Quad ESLs - 63 on - are designed to emulate a point source, so should not be stacked. The proper way to use multiples is in an L configuration.

Whereas 57s are stackable because of their size and shape and even possibly 988s,2805/2812s could be (but who'd want to?), the larger, taller versions simply couldn't be. I don't understand 'L configuration'; how does that work? The only way that multiples of these could be used (in large wide rooms) is side by side. Guess this would give even more of a 'wall of sound' effect, though I doubt that any other parameters would be enhanced.

I'd like to read these reports of added extension with the larger panels. Can you provide links?

'These reports' are purely from forum threads/others' experience of theirs and mine etc. Someone up thread did specify the amount of extra bass extension from the 6 panel models (<5dB?) which really isn't much although it had the advantage of coping with extra welly, I believe. To some, there were pros and cons re. musicality. I really don't care, as, apart from maybe some American models in the past, the Quads are about as big as are obtainable (to my knowledge).

It'll be interesting when my 2905s come back from Quad later this week with all new 'uprated' panels and glue.. Having got used to the superb properties of PMC Twenty.26 for many months I might suffer from culture shock for a while.

Wouldn't it be nice to incorporate my PMCs with the Quads, with another amp if necessary but even if there was room (there isn't !) I doubt the timing etc would integrate sufficiently to create an upgraded listening experience. They are poles apart but with individual salient properties.

 

[Mike Reed]

Seems that I now have 2912 (or 2812) panels in my 2905s. I do wonder if those panels account for any differences between my '05s and the '12s of whether any electronic changes were made. the glue's different, of course but that wouldn't affect sonics.

Couldn't believe they'd packed both on one pallet; 170 kg !!!!!!! It was a struggle getting them up the concrete ramp and into my garage and I'm not looking forward to unpacking and getting them to the living room.so won't be in a hurry.