Has anyone tried double CLS

Well! Let us start then by saying the original Quad was stacked not for bass extension but to increase thier limited output which remains Quads Achilles heel.
Then vertical stacking of the Quads made sense. Theoretically you doubled the output. Moreover since the Quad beamed vertically by stacking them you created a line array of sort.
Neither of these is necessary with the CLS. Just ask my neighbors if the CLS has sufficient output.

While intuitvley you may think that having two speakers instead of one that say are 3db at 60 hz may improve your bass response. In fact you will just have 2 speakers that are 3db down at 60 hz.

No I have not tried that but it would be interesting to try if a person had two matched pairs.

Since the CLS panels are mirror imaged you would not want to stack them but put them side by side. One right channel with one left channel edge to edge (side to side).

I would put the narrow side of the panel side by side (to the inside of the stereo channel pair) so that they would physically be the center of the double pair.

Then what you would want to do since you would now have two power supplies per side is to wire them in series for the speaker connection from the power amp (amps).

The hot connector from one of the speaker terminals connected to the ground of the other speaker terminal on each power supply for that pair. A long jumper could be used for this purpose.

Then you would want to connect the speaker cable (from one channel of) the amp (amps) to the hot (red terminal) on one power supply and the ground of the speaker cable (from one channel of) the amp (amps) to the ground terminal on the other power supply.

This would raise the impedance of the CLS speaker PAIRS up to about 3 0HM’s and should make it fairly easy to drive for tube power amps or whatever you are using.

Both power supplies would of course need to be plugged into the wall for AC connection for each speaker pair.

I think that it would work but the only drawback is a wide room would be necessary to accommodate both stereo pairs.

If you are not familiar with series wiring here is a link that shows how it is done with raw drivers.

http://www.bcae1.com/spkrmlti.htm

If you do try this report back and report the results.

Greg, allow them their fun. It will be a time consuming and expensive learning experience. And I'm charmed by their enthusiasm:

Since the CLS panels are mirror imaged you would not want to stack them but put them side by side. One right channel with one left channel edge to edge (side to side).

Good grief!
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I must repeat, the double CLS are not stacked so you do not need ceilings any higher than you need for a single pair. The speakers are wired in series exactly as the gentleman has described and the load to your amp is not as severe as with one pair.You only need to find a used pair of CLS and 1 extra speaker wire per channel( I use 6 separate 3 foot wires)This is a very inexpensive,upgrade that anyone can perform. There is no external crossovers, no extra sub woofers and interconnects, no pain in the ass positioning of a sub to where it sounds best( like I have done trying to get The Depth to disappear)no soldering wire, replacing or upgrading internal parts or connectors,no power supply upgrades,no power cord upgrades.None of the things audiophiles spend small fortunes on trying to improve their sound.If you find a used pair in the $1000.00 range that is the least amount of money for the most improvement you will ever make to a single CLS system.No expensive time consuming learning experience here.The fun and the proof is in the pudding. And in putting together a double pair.I would feel grief to those who spend five times as much money and effort futzing around with power cables and speaker wire upgrades in a vain attempt to better the sound of their single pair.Good grief, don't knock what you don't know and have no hands on experience with.Do you still think that if man was meant to fly he would have been born with wings?

Sorry Lacee, I would never do that. The CLS (Curvilinear Line Source) is designed to provide a single, uniform, wavefront. Good dispersion, not generally a feature of flat electrostatic panels, is achieved using the (single line) curved driver. (Soundlab achieves a similar result using many smaller flat drivers in a curved array.)

Placing two (curved) lines side by side will create addition and subtraction nodes resulting from combining the two offset wavefronts, and will produce reinforcement and/or subtraction nodes all the way out in to the listening space. This cannot possibly reproduce an accurate soundstage hologram, rather just a "wall of sound".

Nor will adding more panels change (extend) the bass response lower than that of a single panel as Greg points out. If you are not getting adequate performance because the amp is having trouble driving an admittedly difficult load, then get a different amp, or perhaps try using an autoformer like the one made by Paul Speltz.

This subject has been covered ad nauseum for years. If you want confirmation of the points I've made, I suggest you speak with Jim Power or one of the other senior technical people at Martin Logan. It's a dead issue for me ;--)

As for stacking the old Quad 57s, that's an entirely different matter. The (individual) electrostatic drivers (1 bass in the middle 3 HF each side) run vertically top to bottom. So stacking 2 of the them still results in a uniform wavefront, twice as strong. A good thing too because 57s didn't play very loud without arcing and burning up! Again, this arrangement didn't increase their upper or lower frequency response specifications, and when Mark Levinson designed his "Super Quad" system, it consisted of subwoofer and super-tweeter units as well.
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