300 Hz Crossover for ESL 11, 13, &15

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rpokuls

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So the new ESL 11,13 and 15 all have crossover frequencies of 300 Hz even though the panel size increases as we go up in model number.

I currently own Montis which has a crossover frequency of 340 Hz. If I wanted to upgrade, then the ESL 13 or 15 would be a clear upgrade path since I'd be getting a crossover
of 300 Hz vs 340 Hz and presumably better bass along with room correction. In addition, I understand that larger panels can be played "louder".

However, if owned a Summit X with a crossover of 270 Hz, then going for the ESL 15 would get me 300 Hz which is going the "wrong way". Yes, bigger woofer, larger panel,
and ARC but a higher crossover frequency.

Would it not make more sense to buy the CLX which is a pure electrostatic speaker down to 56 Hz and then add a subwoofer to handle the bass?

After all, the point of buying electrostatic speakers is to listen to as much of the music as possible being played by electrostatic panels. Remember, if the crossover
frequency goes up, more and more of the music's frequency range is being played through the cones.

Am I missing something here?
 
So the new ESL 11,13 and 15 all have crossover frequencies of 300 Hz even though the panel size increases as we go up in model number.

I currently own Montis which has a crossover frequency of 340 Hz. If I wanted to upgrade, then the ESL 13 or 15 would be a clear upgrade path since I'd be getting a crossover
of 300 Hz vs 340 Hz and presumably better bass along with room correction. In addition, I understand that larger panels can be played "louder".

However, if owned a Summit X with a crossover of 270 Hz, then going for the ESL 15 would get me 300 Hz which is going the "wrong way". Yes, bigger woofer, larger panel,
and ARC but a higher crossover frequency.

Would it not make more sense to buy the CLX which is a pure electrostatic speaker down to 56 Hz and then add a subwoofer to handle the bass?

After all, the point of buying electrostatic speakers is to listen to as much of the music as possible being played by electrostatic panels. Remember, if the crossover
frequency goes up, more and more of the music's frequency range is being played through the cones.

Am I missing something here?

A few years ago I struggled with what to do concerning speakers. Obviously I did not have the choices that you do now. I was using the Summit x with two Decent i subs and it was good but wanted more. Made the decision to go with the CLX and two 212's. I liked what that combo did and really out paced the Summits as good as they are. Beyond that I have upgraded grately the electronics and interconnects and I believe these speakers have more to give. My son has the 13's which is nice but there is something about a nearly full range panel for those of us that like electrostatics
 
ALL ELSE BEING EQUAL, YES you should chase a lower xo freq. But in reality, once you're down below ~400Hz, whether it's 270, 300, or 340Hz is a wash. Better to concentrate on whether the whole speaker can play loud enough in your room, and if the particular woofer/box/xo you're considering has low distortion, or uses too much eq (excursion) or porting to achieve its numbers, or has an underpowered built-in amp, or if your interior decorator tells you it's TOO LARGE or TOO EXPENSIVE.
Larger ESL panels can play louder because they have more area and more area makes them more efficient. Win, win.
 
As someone with large ESL panels, same as on the Neolith, and who has experimented (and measured) dozens of crossover points and slopes between that panel and woofers (several of those as well), I can say that 300Hz to 340Hz range is where the ESL should cut over to the woofer for best blend of performance. The Monoliths original crossover point of 120Hz was ridiculously low and did not work. There was no mid-bass performance in that configuration.

Remember the ESL is operating as a dipole radiator, with equal energy emitted from the front as from behind the panel. As you go lower in the frequency spectrum, that equal, but out of phase radiation starts to cancel out more and more. At 180Hz it's pretty severe. So 300+Hz AND a steep crossover slope (which generally excludes passive crossovers) are required to get the best blend to the woofer.

The woofer also needs to be designed to smoothly handle frequencies up to 500Hz, ideally past 800Hz. That generally means low-end performance is perforce limited. So I configure the woofer element to run from 60Hz to 315Hz, again with steep crossovers. What you are looking for here is to get as good a blend of the impulse response between panel and woofer. A big old driver focused on reaching deep is not it, a driver that has low distortion and a clean impulse response is what's required.

A sub, actually two or more, are a requirement for any serious audio setup, as integration of low-frequencies into the room is best done from multiple, well-chosen locations, which are rarely the locations of the mains.

So to me, given the choices the OP lists, I'd go with the ESL 15, as it has the largest panel, and two BalancedForce 212's and run the DRC on the low-end for both, and then run a Trinnov or Dirac DRC on top of everything. Oh, and treat the room with physical absorption and diffusion before any DRC.
 
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