Best tube amp for electrostatic speakers


For over 35 years I've almost exclusively used either ribbons or electrostats with solid state amplification and have been generally happy with the sound. Over the last several years, though, my hearing has become somewhat degraded and more sensitive to certain frequencies. The frequencies which seem to cause the most discomfort occur in the 1400 to 1900Hz range and come across as "bright" to my hearing. After researching this matter and having been given some expert advice, I've decided to pursue the idea of replacing my present amplification equipment with tube based gear.

The purpose of this post, then, is to solicit advice regarding the best approach to making this decision based on the following information: the current basic equipment is Shanling Solid state CD player, Peachtree Audio Nova used as preamp, two DBX 1531 EQ's to help compensate for age related hearing loss, Peachtree 220 amp, Silversonic T114 cable and Martin Logan Ethos speakers.

The listening area is our living room measuring 15 by 22 feet with my listening position 16 feet from the plane of the 2 speakers which are positioned 11 feet apart measured center to center. Located between the 2 speakers is an entertainment center which is about 9 feet wide. My listening interests are varied from solo guitar and light jazz to occasional orchestral music. I don't generally listen at high volumes and am not particularly interested in strong bass except for the rare action movie background.

Unless not advisable for some reason, I would like to keep the Peachtree Nova as a preamp because of the significant latitude for source connection and what seems to have a decent internal DAC. If this option would substantially defeat the purpose of the intended modification I would work around it. I can no longer deal with sounds that are "bright" which I now find uncomfortable but detailed sound is very important.

So, the questions are: is the move to tubes the best option and, if so, what might be some reasonably priced amps that could accomplish the goal. This, of course, would take into consideration room size, etc. for determining power requirements. If there are other more practical and less expensive options to consider, I would appreciate that advice as well.
128x128broadstone

As I said Ralph, I have had a pair of Zero Autoformers given to me, and used them a few times and regarded them as banaid fix for mismatched amp/speakers combiations.

As for your continued accusations of me trolling you (again popycock) and if I were it's better than being a shill.

The OP's wants to buy an amp for his ML Ethos speakers, why would he buy an amp that is not suited and then buy Autoformers as a bandaid fix to make them compatible.

Cheers George
FWIW, all very good ML demos I have heard over the years have been with very good SS amplification. Classe, Krell and that ilk. I don't recall any with tube amplification so can't comment there. Ml does not seem like a company that would design their gear to work best with tube amps. That's not to say that many tube amps might not sound quite fine as well.
Mapman ... .5 ohm in high treble is a near short. Hard to believe that ANY amp could drive clean power into that kind of load. But look ... if Ralph (Atmasphere) and other smart guys say that MLs work well with the right amp, then so be it. Personally, I wouldn't hook my amp up to those speakers with such a crazy impedance curve.

Right now, I am interested in auditioning a pair of Magico S-5s. Take a look at the NRC specs on these beasts here:

http://www.soundstage.com/index.php?option=com_content&view=article&id=1043:nrc-measurements-magico-s5-loudspeakers&catid=77:loudspeaker-measurements&Itemid=153

Low impedance ... yes. Nominally 4 to 6 ohms. But flat ... really flat. I surmise that my amp could drive the S-5s very nicely off the 4 ohm tap. The distortion figures and FR specs are unbelievable. Would probably still need my DEQX to correct for my room problems and to straighten out the high order crossover/time coherence issues.

If I sprung for the S5s, I'd probably dump my subwoofer and just go with the S5s flat out. Biggest issue is with my wife.
Hi Bifwyne even the Magico S-5s are a hard load, just because they are a quite flat impedance, they are still 2ohms 50hz-80hz and then 3ohms 7khz-20khz.
But this isn't the only reason that them a heavy load.
It's the -phase angle at those impedances, which are -45 degrees at 50hz and -35 degrees in the mids/highs. (last graph on your link)
This will make the 2ohm load and 3ohm load look more like 1ohm and 2ohm to the amplifier, quite savage.

When you combine low impedance and high - phase angle as this, it's called EPDR (equivalent peak dissipation resistance) and the amp sees this as a much low resistive load.

Read about EPDR here, 5th page down under Lab Report. On the Wilson Alexia's It's PDF so you have to open it. I'll post more links on this EPDR if anyone's interested.

http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CCIQFjAB&url=http%3A%2F%2Fwww.absolutesounds.com%2Fpdf%2Fmain%2Fpress%2FWA%2520Alexia%2520HFN%25200313-4web.pdf&ei=LFLAVO-6L8LVmgWqyICoBA&usg=AFQjCNEZq3-yhO0zaUOpAjBxXfWo_vYFLQ

Cheers George

If I'm not mistaken, power demands increase exponentially with lower frequency, so a .5 ohm impedance at high frequencies is much less problematic than when typically found in the bass region.

I just know what I've seen and heard over the years with ML speakers in general. They sound top notch with top notch SS amps. Relatively few ML owners use tube amps I would think. Tube amps have never been in the picture.

Yes Ralph is a very smart guy, but he is also a tube amp vendor and well qualified to defend his turf.