Any Opinions about Innersound ESL amps?

I'm thinking of increasing the power to my Martin Logan CLSIIz's. I currently have a Marsh a400s and considering trying the Innersound ESL Amp or Innersound ESL monoblocks.
Any opinions would be appreciated.
Hbrandt, I just did a search on "innersound" at the main forum page and it came up with a lot of hits. You may find what you are looking for or at least someone who owns one that you could email.
We have a bunch of Roger's stuff, but haven't been in the market for amps. He knows his stuff and he is one of the best support experiences EVER.
Good Luck,
I remember seeing some VERY positive comments about these amps in previous Audiogon forums. I'm sure that somebody with direct experience will respond sooner than later.

Out of curiosity, what about your Marsh aren't you satisfied with ? I take it that you feel that it is running out of steam ??? Sean
Sean: I love the Marsh amp...but I think it does have some trouble with the voltage draw and the impedance drop of the electrostats. Before I unload the Marsh..I plan on extensively comparing it with the new amp.
While i don't know how well it would match with the sonics of your system or personal taste, i've been told that the Sunfire amps also work quite well with E-stat's and Planars. You can usually find the "little" 300 / 600 wpc version for a pretty reasonable price. If you really want some "muscle", try the 600 / 1200 wpc Signature version. That amp will drive ANYTHING that you throw at it. Just a thought... Sean
Hi Hbrandt, I have to reply as my middle name is Brandt and I own and sell the Innersound ESL amps (and product line).
The ESL amp is specifically designed to drive electrostatics and puts out 600 watts per channel into 4 ohms. A local dealer has the Marsh amp and it doesn't drive the Soundlabs very well at all but the ESL amp (they also carry them) has no problem gettting the most from the Soundlabs, which are as hard to drive as anything out there. As for the sound quality, I believe they really compare to the very best and you might want to go to to read what 3'rd party reviews of the amp have to say. If I can answer anything else for you or help you acquire one, please let me know.
Hello HBrandt:

I currently use the ESL amp for my CLSIIZ's, and can't imagine a better amp for them; it is such a great synergy. The ESL amp gets all of the smallest details, and is capable of greater dynamics than I've ever heard with CLS speakers. It never sounds the least bit strained or hard, even with very dynamic peaks, and is purpose-built for 'stats. I have also used the ESL amp with the Innersound Eros, and various models of Acoustats, and it was also better than any other amp I have ever used with these. Furthermore, I paired it with current-hungry Apogee Duetta Signatures and Gallo Nucleus Reference speakers, with very impressive results. I give this amp 5 stars (at least), and it could find a home in many systems. The support from Roger Sanders for his products is without equal in my experience, and he has been very generous with tech support and information. Good Luck
We're a tube kinda couple, but when my wife and I compared the Innersound ESL amp to our 400 watt customized Melos monoblocks, an ARC VT-200 and Threshold Stasis SA-2's we were mighty impressed. We tried the combo on the Eros and our old full range Acoustats. We highly recomend it for electrostats.
Well, based on the excellent feedback about the Innersound amps, I decided to take the plunge and order a couple of Innersound ESL Monoblocks. After I get them, I'll post a comparison with the Marsh a400s right here!! Thanks for all your help, folks! I happy!! Finally, an audio decision that worked out. I received my Innersound ESL Monoblocks from Innersound and I am incredibly impressed. I underestimated the difference that moving from the Marsh a400s (330 w/ch. 4 ohm)to the Innersounds (1200 w/ch. 4ohm) would make. The Martin Logan CLS IIz's, like most electrostats are a difficult and reactive load. I thought the Marsh was doing a pretty good job, but it would occasionally go into protect mode at high volume.

The new amp does just about everything the Marsh did well. Pure rich detailed sound without coloration. The Marsh was a bit extreme in the high end and I'm finding the Innersounds to be a bit more refined in that area. But the major difference is the expansive soundstage and energy of the extra power into the electostats. The tight midbass punch is superb. Symphonic music, in particular, sounds more realistic.

My next step is to compare the Innersound coaxial speaker cables (which I'm currently using) to my Tara The One Reference speaker cables. I sent the 10 ft pair back to Tara to have them cut into a 6ft pair and a 4 ft pair and reterminated. They should be back next week and I'll post the results here.

Also, I should say that Roger Saunders has been great to work with at Innersound. He has spent a lot of time on the phone with me explaining about the science of electrostats and his amps.

Needless to say, I'm a happy camper in audio nirvana!!!
Great to hear! Roger really turned those amps around for you fast,didn't he? Roger does cultivate customer loyalty, doesn't he?
WOW !!! Great to hear the results that you're getting and glad that you're happy. So far, it sounds like you're "sold" on those babies.

As to the difference between 330 wpc and 1200 wpc, i can believe that it would make a difference, especially with a reactive load such as E-stat's. However, i think it has more to do with the design of the amp / interface with the speakers more than anything.

I'm basing this on the fact that i was running my HT mains with a conservative 900 wpc ( 400+ from 200 Hz up and 500+ below that ) and then switched to a single amp that does 1200 wpc at that impedance. While 900+ wpc should have been plenty, i could still drive the amps into compression and it would get smeared at "volume". With the newer amp, the sound is effortless and NEVER sounds strained. Even at 117 db's at 10', the sound is completely clean. Due to the complete lack of grain and "smearing", it doesn't even sound "aggressive" at that level.

I would imagine that your situation resulted in similar findings. Since the amp is not being "pushed" nearly as much or run up into the "danger / protection" zone, it probably sounds far more open and relaxed with greater bass control / impact. While most folks would consider the 330 wpc that you were running to be "big power", they will never know the difference that BIG power makes in terms of ease, definition and control. Sean
I was informed that I spelled Roger's name wrong. In fact, it is Roger Sanders!!! Sorry!!!
Hbrandt: Sorry is not good enough. I just got off the phone with Roger and he will be stopping by this evening to pick up the amps. Better luck next time, it was good while it lasted.
dk: that one's a classic! just try to avoid run-on sentences and we'll let you keep your computer. -kelly