Sanders ESL Amplifiers

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ML4Life

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Anyone have any experience with these? Just read about these Mono's and thinking of getting a pair for my CLS....
 

Robert D

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If you get them, please report back on what you think of them. Those look like great amps and they are priced better than a lot of their competitors.
 

wink

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Grab them! You won’t regret it. These amps are specifically designed to take the load of an electrostatic speaker. And they sound pretty damn good too.
 

john65b

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I actually have one that may be for sale. It's the amp that has internal crossover and can be used for the bass or HF. I have jumpered it so it is actually a full range integrated amp. I actually emailed Roger on it and he said I nailed it. The jumper mod is 100% reversible in 5 minutes.

If you are near Chicago I can audition
 
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I have the magtec. had the ESL. either will make you very happy. if you order direct, see if you can get 20amp version. they love reserve current. do not use power conditioning with these amps...will strangle them. direct purchase gets you lifetime warranty. there is a reason they look just like CODA amps...inside...
 

Rich

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These are awesome amps. I have a pair of the monos. Clean, neutral sound and gobs of power. Ultimate control over the esl panels. Highly recommended.
 

Big Dog RJ

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Roger that maties!

Few decades ago, I attended a special invite only demo (Sth East Asian region) that comprised of a group of ESL engineers, where the dealerships were getting together to demo the latest ESL gear. This team of engineers had worked closely with Gayle Martin Sanders, and Roger Sanders. I was in awe when I met each of these chaps during a show, and learnt a heck of a lot more than reading through the usual TAS & Stereophile issues...

There was the Monolith being driven by Spectral gear. The CLS were driven by a full array of CJ's Premier series amplifiers and there was another ESL speaker which I hadn't seen before, Inner Sound. Driven by a full line up of ARC gear, it was marvellous! Then after talking to Roger Sanders briefly, I gathered there were some new things coming soon...

Quite a while after that event, I came across the Sanders ESL's driven with his own amplifiers, specially designed for ESL's, the Magtec. So I asked Roger what about Inner Sound, well his new version of those were what was exactly playing! Roger made two ESL's models, one being slightly larger than the other and both having straight panels with no fix tilt unlike ML's. Upon first impressions, I was quite surprised how this very normal looking unassuming amplifier drove his ESL's so effortlessly! The sound was full, with great authority, excellent soundstage depth and a sense of a real live stage! It was nearly tube like in nature and the amplifiers ran cool! So I asked him all about these amps, and he told me the whole story...

At the end of the day, it's all about high current capacity and stable voltage that drives ESL's effortlessly. If the amplifier only has watts/power and doesn't hold stable down to less than 1 Ohm then it's not good enough to handle ESL's. At the same time, if it can handle 4 Ohms and below but has unstable voltage, power supplies will lose their capacitance, eventually running out of puff... again not a good design with ESL's.

In his Magtec amplifiers, he has designed them to handle vasts amounts of high current, along with highly stable voltage and power on tap. So, basically all three factors comprised in one chassis, real VFM! There are stereo versions and monoblocks if you really want to blow the roof off. However, that much of power isn't really required in most "normal settings" in average sized rooms.

Comparing the Magtec monoblocks to Pass Labs XS300's isn't really fair, given the huge price difference! However, performance based, although I certainly prefer the Pass Labs, I could happily recommend the Magtecs, absolute VFM! I couldn't fault them in any way whatsoever and they certainly do a fine job of driving ESL's optimally.

At the end of the day though, I'm truly passionate about tubes and I use only conrad johnson gear to drive my CLX's, it's just a personal preference.

If any of you are considering Magtec amplifiers, I would highly recommend them, you won't be disappointed. In order to make your custom sound more engaging and effective, the choice of preamps, source gear, and ancillary gear will come into play more than just the amplifiers. It's all about synergy!

Cheers, and enjoy those fine tunes!
Woof! RJ
 

Scorpio1951

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I've owned a pair of Sanders Magtech monoblocks for over 5 years. No problems, very happy with them, using them on the 15A's.
 

JonFo

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Anyone have any experience with these?
I have a Sanders ESL amp, with the latest thermaltrack boards, and it powers my large Monolith panels wired direct (no crossover, it's an active system, the XO is ahead of the amp). So it's having to deal with the full back-emf and capacitance of the naked panel. Does not break a sweat and can play at a crazy high volume, I was considering the use dual monos, but I don't need that.

I highly recommend these for ANY ESL application.
 

Robert D

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Whats the difference between the two amps he has? The Magtech and the ESL Mark II? I see the Magtech has 100 watts more power and costs a bit more, but the webpage says that the Magtech is perfect for ESL speakers too.

and

 

JonFo

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Whats the difference between the two amps he has? The Magtech and the ESL Mark II? I see the Magtech has 100 watts more power and costs a bit more, but the webpage says that the Magtech is perfect for ESL speakers too.

and

The magtech is the slightly better all-around amp, it will deal better with dynamic speakers, but is equally happy with demanding ESLs.

The ESL model is plenty powerful, and if driving ESL speakers, pretty much all you need.
If the extra grand difference in price is important, and you have ESL speakers, then an easy choice to go with the ESL amp.
 

Robert D

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How is it that his speakers are immune to humidity, dust, and dirt? If this is true, its a definite advantage over Martin Logan. I cannot imagine though how it can be true. From his webpage:

"Roger's "Ultrastat" panels will play at ear-bleeding levels, cannot be arced, do not use or need protective circuitry, are immune to humidity, dust, and dirt, and do not need or use dust covers. They can be driven by multi-thousand watt amplifiers without damage. They are more rugged than conventional magnetic drivers. They do not fail and are so robust that they come with a lifetime warranty."


That package for $20,000 seems like a fair deal especially since the speakers come with a Magtech stereo amplifier. I cant remember, does anyone here own some of these speakers? Im going to guess that they too wear out after time and need to be replaced? With his lifetime warranty, I guess he would supply you with new panels for free?
 

Robert D

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The magtech is the slightly better all-around amp, it will deal better with dynamic speakers, but is equally happy with demanding ESLs.

The ESL model is plenty powerful, and if driving ESL speakers, pretty much all you need.
If the extra grand difference in price is important, and you have ESL speakers, then an easy choice to go with the ESL amp.
Ok, thats what I figured. I cant imagine needing the monoblocks. The stereo amps both have ample power. Right now I am using an Aragon stereo amp with 200 watts per channel and its good. Sander's ESL amp has 400 watts and the Magtech 500 W. So at least 2x what I have now. I dont find myself feeling too much in need of more power now.
 

Robert D

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Oh ,and Sanders has his speakers being dual amped, so each channel only has to drive either a woofer or a panel and not both. My Aragon now is driving the whole speaker and it seems ample. Id love to hear my speakers biamped with his amps.
 
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Russr

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How is it that his speakers are immune to humidity, dust, and dirt? If this is true, its a definite advantage over Martin Logan. I cannot imagine though how it can be true. From his webpage:

"Roger's "Ultrastat" panels will play at ear-bleeding levels, cannot be arced, do not use or need protective circuitry, are immune to humidity, dust, and dirt, and do not need or use dust covers. They can be driven by multi-thousand watt amplifiers without damage. They are more rugged than conventional magnetic drivers. They do not fail and are so robust that they come with a lifetime warranty."


That package for $20,000 seems like a fair deal especially since the speakers come with a Magtech stereo amplifier. I cant remember, does anyone here own some of these speakers? Im going to guess that they too wear out after time and need to be replaced? With his lifetime warranty, I guess he would supply you with new panels for free?
Good question(s)! Following...
 

Big Dog RJ

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Attn: Rob D

Yes, when I first read those comments/ specs on Sanders ESL's, I thought to myself that these must be the ultimate! However, after subsequent discussions and my disastrous experience with Quad ESL's... only did I realise the true benefits of Sanders ESL's. So unlike Quads, Sanders ESL's don't arc, they are built on high standards to tolerate very high dynamic peaks, and they're not as susceptible to environmental issues, such as dust, humidity and tropical climes... which the Quads were always prone to!

So, it's pretty much a slight marketing spin- won't arc, impervious to dust & etc , and can play at ear bleeding levels... basically the very same standards as ML! Absolutely no difference. The only major difference being ML has curved panels and some with a fix tilt angle backwards... their dispersion pattern is slightly different.

Anyway, after our last chat, I gathered who would ever want to listen to music at ear bleeding levels? You'd go deaf! As humans, our natural hearing abilities have fairly high tolerances but pushing those levels to extremes constantly will render us deaf! So there's no way we can listen to music at high levels at length without ending up with ear pain... eventually ending up deaf.

In fact I ordered and sold one of his ESL's to a customer, that was the Model 10 series I think. We also set his system up with the Magtec monoblocks and his preamp was a tube version from Sonic Frontiers. A marvellous combination! I think that customer still has this system, never really wanted to upgrade it to anything, happy as!

Whether they're related or not... I was under the impression they were but I don't think so.
Speaking of unusual panels, there's another chap who makes an interesting ribbon panel hybrid with dynamic drivers, called GT Audio. Based in the US, he goes as George Takesh and claims that his panel hybrids are superior in terms of dynamics and large scale music reproduction. I have heard his models on several occasions and they did impress but I just prefer full range stats.

All three of these chaps know each other and have been involved in technical discussions sharing expert knowledge but none of them cross each other's paths... that's respect! True gentleman and pure engineers!

Cheers, RJ
 

JonFo

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Are Roger and Gayle Sanders related? Are they brothers?
No, I think it is just a coincidence.

One of the things I really like about Roger is he has been pursuing the ideal ESL amplification goal for a long, long time. Decades ago, he created an ESL direct-drive amp that had amazing performance, but was a bust in terms of a possible product due to cost, complexity, and most importantly, danger. Direct-drive means it is powering the stators directly, and at very high voltages (~5Kv ). No step-up transformer is needed here, just very careful connectivity to keep people from frying themselves. The beast was all tubes (IIRC, some were from radio stations that use high-power/voltage tubes for transmission ) and it was effectively a whole-home heater as well.

In the Monoray brochure, I describe a modern interpretation of the direct-drive concept using modern high-voltage FETs and leveraging the DDFA architecture (which I called Dynamic Direct Panel Drive (DDPD) ) for implementing feedback-driven closed-loop amplification that should handle the complexities of an ESL quite well.
My solution to the 'danger' part is to specify a custom umbilical cord with locking (and safe) connectors between the amp and speaker units.

Re-reading my posts and docs on the Monoray, I sure wish someone would produce that, it would be killer.
 

Big Dog RJ

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Yes, vaguely remember this being mentioned and Roger sharing some pics... it was a pretty massive affair. Like you said, dangerous goods!!! Also during that time, CJ put out a prototype monoblock consisting of a 300B single ended pure Class A amplifier. It was huge but never got off ground due to materials and cost, plus production feasibility was unlikely. So it was shelved until only now CJ has introduced two ART series amplifiers in Class A. However, they don't use SE versions of the 300B, rather KT88's in push-pull Class A (48grand a pair), a true Jeff F classic! I don't think they ever liked the 300B for whatever reason.

Similarly, with ESL's, I think there are quite a number of prototypes that never took off ground, simply due to reliability issues. Many of those earlier designs were shelved.

Direct drive from the main amplifier does make sense, such that it would eliminate several stages from the amplifier. The output stage would ideally be tubes since they're high voltage devices. This would have resulted in a purer sound... that would've certainly been a revelation!

Cheers, RJ
 
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