Stacked Quad ESL 57

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Recently, I have a conversation with peoples about stacking Quad ESL 57. One says the low impedance of stacked Quad ESL 57 (0.9 ohm on high frequency) mainly because of the high capacitive, that is no good to tube amplification at all.

Assume room size and ceiling height are not an issue, how come people don't use 4 pairs in stacking? They can putting 2 for a set and wired in series, then parallel both sets, the nominal impedance should be equivalent to the ONE SINGLE pair ESL 57 that is 8 ohm and min 2 ohm on high frequency.

Is the capacitance issue (at high frequency) really that serious even under series-parallel approach describe above??
 
In the 1970's, Mark Levinson produced the HQD system, comprised of stacked pairs of Quad-57's mounted in a custom oak stand with a Decca ribbon-tweeter mounted horizontally between the Qual-57's, augmented with 24" HARTLEY Model 224HS woofer system, powered by two pairs of Mark Levinson ML-2 25W Class-A solid-state power amplifiers. No WAF; if you aren't single when you buy them, you soon will be... :cool:
 
One lovely thing about Quadruple Quad ESL 57, we can have the frame made for adjustment for EACH set of Quad to match the actual room requirement. Second, the system no longer need a supertweeter as the treble x 4 per channel works with ease. It might be a beaming issue existed, but can be cured by either adjustment mentioned above or digital acoustics correctional system we have nowadays.

The only concern I have is its "high capacitance" might cause the roll off on the high frequency by tacking 4 x ESL 57....??


I know someone with a "quad" :) Esl57 and a number of them with triple stack and dual stack ..

The Dual stack sounds the best unless you have a really, really big room ...
 
If you put four of them series/parallel then the impedance is equal to one speaker. So the load the amplifier sees should be the same as for a single pair. But... you will need to drive them with higher input voltage (and thus higher current) to actually get more power out of 4 ESLs. So that increases the demands on the amplifier.

Best solution is to give each speaker it's own amplifier. Quad 303 is affordable and a known good combination with the Quad ESL. And if you are willing to go the route of 4 amps then tube's are a possibility again.

I would put a Hypex NCore module in each speaker and have custom transformers wound with lowered step-up ratio that is now possible with the output of these modules. That should give you a killer setup! Then if you favor tube sound you can put a nice pre-amp in there to voice the system.

But driving 4 sets of Quads from a single tube amp... I would not recommend that.
 
Dont forget the earthing issues.

Best solution is to give each speaker it's own amplifier. Quad 303 is affordable and a known good combination with the Quad ESL. And if you are willing to go the route of 4 amps then tube's are a possibility again.

I agree the Quad 303 is a great match for the ESL 57 and has a real good retro look that just works with the ESL 57, and has been destined for and to avoid overloading the ESL 57 and causing damage. The Quad 303 is noisy by modern standards ( you probably wont need to worry about the little hiss that you only hear with your ear near the speaker)

Using multiple Quad 303's I would use line transformers between the Quad 303 and your preamp to isolate the earths for simplicity. Because the Quad 303 regulates the earth rather than the HT voltage you cant connect the earths of the Quad 303 together or you will fry the regulation on the amplifiers. I have done this so many times before I worked this out I feel stupid.

The Quad 303 is a great partner for the ESL 57, and is nice that at factory spec levels they cant destroy the ESL 57 with overloads I believe.

Best of luck.

Owen
 
I fail to understand how stacked ESL 57 s can work well. The ESL57 has a very narrow vertical dispersion. The horizontal dispersion is wider but isn't that broad. If you aren't sitting at the right height you don't hear the treble. How can 2 or even worse 4 provide more that a single sweet spot with careful positioning.
 
I fail to understand how stacked ESL 57 s can work well. The ESL57 has a very narrow vertical dispersion. The horizontal dispersion is wider but isn't that broad. If you aren't sitting at the right height you don't hear the treble. How can 2 or even worse 4 provide more that a single sweet spot with careful positioning.

I have never had the possibility to try this, but I agree with your concerns that the treble panel will be very directional. The reason is for the maximum volume producible, and the lowest frequency producible.

My expectation is that since the high frequencies are so directional that if the two panels are misaligned you might even have two sweet spots. Careful positioning will be essential. If I was doing this I would suggest that the stand would be critical, and it should be adjustable, to reduce the issues you and I suspect would occur.

If I could bring my self to modify such a classic as the ESL 57 (Sort of like modifying a 1960's classic car with a modern engine). I might even adjust the drive electronics, to make the system a three way (With a DIY electrostatic tweeter, and call the high frequency panels on the ESL 57 as mid ranges). But if I was going this way I personally would be more tempted to start with ESL 63 panels and drive electronics, and stack the bass panels either side of a ESL 63, either making a taller or wider speaker than an ESL 63.

I suspect sealed or dipole bass under an ESL 57 with an active crossover is both a cheaper and more pragmatic solution to maximum volume and limited bass performance of an ESL57.

Honestly the ESL 57 is very good as designed, and already a very large and potentially dominating speaker in most European sized rooms. But you already need to be a music professional or Hifi obsessive to want an electrostatic speaker, and the accompanied experience, we are not mass market in this forum, and this "Planars & Exotics" topic.
 
Proper stands and adjustments are super critical , very much so on triple and quad panel setups . Todate the double sounds best to me and the triple sounds most majestic in a large room , recreating the power and size of a symphony with ease, you do need a big , big room to get far enuff for them to work.....

I want to believe a curved array is best ...
 
To realize a double stack and come at least close to a single pair in accurate impulse response would make the upper pair be angled down and forward of the lower pair as if drawing an arc vertically and equal distance from the listener.
I remember a drawing from John Koval I vaguely remember many moons ago, showing this configuration while at his house listening to some apogees.

This ugly setup would preserve what a pair does better than 4 this side of more bass and loudness capability
Any other straight up stack will compromise in some way what a single pair does so wonderfully
Tearing them apart and reconfiguring their arangement as some have done seems appropiate as long as time alignment is considered
IMO
You will gain something and lose something depending on your priorites

Regards
David
 
riple and quad panel setups . Todate the double sounds best to me and the triple sounds most majestic in a large room , recreating the power and size of a symphony with ease, you do need a big , big room to get far enuff for them to work.....[/QUOTE]

Very interesting to hear, my room would just not support that scale of speaker. Lucky you to have the space.

I want to believe a curved array is best ...

Maybe I am thinking about this wrong but I don't understand how a curved electrostatic driver can work well, and a array of electrostatic speakers arranged in a curve seems unnecessarily complex, when designs like the ESL 63 seem so much more elegant in solving sound dispersion.

Just my 2 cents.
 
I have conversation with my friend recently, and he prefers wired the Quad ESL 57 all the way in "parallel", and this is what he told me: "......there is a benefit to going parallel. Speaker wires in series will play off each other's load, and since they will never be acoustically loaded the same, their outputs will vary between them...."

To have the zero impedance autoformer between the power amplifier and the BIG Quad ESL system to cure 2 problems:

1) The low impedance by paralleling 3 to 4 pairs of ESL 57

2) The Autoformer can completely eliminate the high capacitive issue.

Autoformers offered by ZeroImpedance- Improve your speaker sound quality with the use of an autoformer.

For the best performance with such a big stacked Quads system, it's better to have a Supertweeter centrally in each gap. This will require three pairs of Supertweeters and a gap of at least 32mm between the Quads.

IMG_1541.jpg Photo by jloveys | Photobucket

Finally the stand for 4 pairs stacking should be "angle adjustable" for individual ESL 57.

:)
 
Gradient SW-D

Yes, have discussed with my friend and he has thought of the Gradient SW-D in stacking! Each SW-D has 4 x 12" drivers in dipole configuration and specially made for Quad ESL 57. It will have 8 x 12" drivers per channel by stacking the SW-D, and it nominal impedance is 4 ohm.

But concern about the physical stability since it's over 9 feet tall and might have a problem for one SW-D sitting on the others.....also crossover point is another issue. Unlike the 63/2805, the ESL 57 doesn't like any subwoofer and woofer of any kind with cut off at 100Hz or above based on people has tried b4. But hard to say what will happen with some digital bass eq or acoustics correctional system.



I have never had the possibility to try this, but I agree with your concerns that the treble panel will be very directional. The reason is for the maximum volume producible, and the lowest frequency producible.

My expectation is that since the high frequencies are so directional that if the two panels are misaligned you might even have two sweet spots. Careful positioning will be essential. If I was doing this I would suggest that the stand would be critical, and it should be adjustable, to reduce the issues you and I suspect would occur.

If I could bring my self to modify such a classic as the ESL 57 (Sort of like modifying a 1960's classic car with a modern engine). I might even adjust the drive electronics, to make the system a three way (With a DIY electrostatic tweeter, and call the high frequency panels on the ESL 57 as mid ranges). But if I was going this way I personally would be more tempted to start with ESL 63 panels and drive electronics, and stack the bass panels either side of a ESL 63, either making a taller or wider speaker than an ESL 63.

I suspect sealed or dipole bass under an ESL 57 with an active crossover is both a cheaper and more pragmatic solution to maximum volume and limited bass performance of an ESL57.

Honestly the ESL 57 is very good as designed, and already a very large and potentially dominating speaker in most European sized rooms. But you already need to be a music professional or Hifi obsessive to want an electrostatic speaker, and the accompanied experience, we are not mass market in this forum, and this "Planars & Exotics" topic.
 
I have conversation with my friend recently, and he prefers wired the Quad ESL 57 all the way in "parallel", and this is what he told me: "......there is a benefit to going parallel. Speaker wires in series will play off each other's load, and since they will never be acoustically loaded the same, their outputs will vary between them...."

To have the zero impedance autoformer between the power amplifier and the BIG Quad ESL system to cure 2 problems:

1) The low impedance by paralleling 3 to 4 pairs of ESL 57

2) The Autoformer can completely eliminate the high capacitive issue.

Autoformers offered by ZeroImpedance- Improve your speaker sound quality with the use of an autoformer.

For the best performance with such a big stacked Quads system, it's better to have a Supertweeter centrally in each gap. This will require three pairs of Supertweeters and a gap of at least 32mm between the Quads.

IMG_1541.jpg Photo by jloveys | Photobucket

Finally the stand for 4 pairs stacking should be "angle adjustable" for individual ESL 57.

:)


Correct you want adjustability of each panel to shape the curve towards listening position. The gradient subwoofer is not worth the effort , poor sonics and not enuff output IMO , a double and or triple stack has plenty weight , those subs wont make a dent ....


Regards
 
Those Auto transformers are awful expensive !!!
Not to mention $600 for a pair of cherry wood boxes with some run of the mill gold plated binding posts!!

You can probably accomplish the same thing using a pair of toroidal power transformers (such as the antek's) with two 120v winding's each and wire the 120V winding's in a 2:1 step-Down configuration.

I did a test of running one of my two-way speakers straight through 1:1 using the two 120V winding's and found the sound to be the same as without using the transformer.

I only detected a very very slight muddiness on the very extreme low end below about 60Hz or so, But nothing that ruined the quality of the overall sound.
I suspect that this was caused by the amplifier having less control and dampening effect on the woofer due to the interfacing of the transformer or that that I just needed more core area for such a low frequency extension.

Everything else was great!

This test was done to test the ability of the transformers core for audio use, particularly for ESL's before I had actually tried it as a step-up for my ESL.

FWIW

jer :)

P.S. You could do this using either, one or two cores.
Using two cores may give you better low frequency performance.
 
Last edited:
To have the zero impedance autoformer between the power amplifier and the BIG Quad ESL system to cure 2 problems:

1) The low impedance by paralleling 3 to 4 pairs of ESL 57

2) The Autoformer can completely eliminate the high capacitive issue.

Autoformers offered by ZeroImpedance- Improve your speaker sound quality with the use of an autoformer.

For the best performance with such a big stacked Quads system, it's better to have a Supertweeter centrally in each gap. This will require three pairs of Supertweeters and a gap of at least 32mm between the Quads.
Dear Tubenstein,

Since you seem to like Quad II amplifiers and ESL 57's, and the cost of a pair of Autoformers by ZeroImpedance cost about the same as a pair good condition refurbished Quad II amplifiers, why not just spend the few pounds extra and buy a Quad II amplifier per speaker, the resale value of Quad II's is higher should you change your mind later, the sound will be more predictably a scaled up version of what you have with one amp, and I suspect the sound will be better than parallel or autoformer based matching.

Best of luck what ever you do. Owen
 
Sorry! This is my friend's system not mine. I just helping him to gather more opinions for consideration :)

Normally big speaker systems are very hard to control and setup.



Dear Tubenstein,

Since you seem to like Quad II amplifiers and ESL 57's, and the cost of a pair of Autoformers by ZeroImpedance cost about the same as a pair good condition refurbished Quad II amplifiers, why not just spend the few pounds extra and buy a Quad II amplifier per speaker, the resale value of Quad II's is higher should you change your mind later, the sound will be more predictably a scaled up version of what you have with one amp, and I suspect the sound will be better than parallel or autoformer based matching.

Best of luck what ever you do. Owen
 
303 is a class B amplifier if my memory serve me proper?

I agree the Quad 303 is a great match for the ESL 57 and has a real good retro look that just works with the ESL 57, and has been destined for and to avoid overloading the ESL 57 and causing damage. The Quad 303 is noisy by modern standards ( you probably wont need to worry about the little hiss that you only hear with your ear near the speaker)

Using multiple Quad 303's I would use line transformers between the Quad 303 and your preamp to isolate the earths for simplicity. Because the Quad 303 regulates the earth rather than the HT voltage you cant connect the earths of the Quad 303 together or you will fry the regulation on the amplifiers. I have done this so many times before I worked this out I feel stupid.

The Quad 303 is a great partner for the ESL 57, and is nice that at factory spec levels they cant destroy the ESL 57 with overloads I believe.

Best of luck.

Owen
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.