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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
broadstone's avatar
broadstone OP
277 posts
 
Atmasphere, in each system that I used for this test the players were different; one is my own which is the Shanling CD-100, another is an old Theta, and the third source is our Apple TV playing Apple lossless files. The results are the same in all cases using multiple CDs when the offending frequencies come up. For example, I can't listen to anything Celine Dione sings except at VERY low volume. Mostly, though, because much of my listening is to solo guitar, there are only a few passages that bother me so, yes, most most of what I listen to is pleasing and I generally enjoy my system very much.

Labtec, I got out the old test CD and tried listening to pink noise but didn't quit get the part about a comparison. The test disk presents pink noise starting at the left speaker, then right, then simultaneously, both in and out of phase. The thing I didn't expect nor understand is that the out of phase sound was almost exclusively from the right speaker. I'm sure I'm missing something here.
georgehifi's avatar
georgehifi
4,966 posts
 

Broadstone Hi.

Written bench test results from one review on ML Ethos:
"Measured overall impedance was low at 4 Ohms, in fact surprisingly low considering the bass unit is powered. This is due to the electrostatic panel that comes in hard at 400Hz our impedance analysis shows, careering down to 1 Ohm at 20kHz – ouch!"

I'll look for graphs that back this test statement up.

But from what was said to get the very best from the ML Ethos you need an amp that can that can deliver good current down to at least 2ohms, so it stays flat over the frequency range, and not start behaving like a tone control at different load impedances.

That means "close" to doubling the 8ohm spec wattage to 4ohms and again doubling to 2ohms

EG:
8ohms-50watts
4ohms-100watts
2ohms-200watts

Cheers George
broadstone's avatar
broadstone OP
277 posts
 
George, this is my 6th pair of Martin Logans and I've seen the graphs so your observation is absolutely correct. I'm using a Peachtree Audio 220W power amp but I don't know how adequate its current capabilities are in regard to the impedance increases that you describe. However, I'm 72 and starting to be convinced that a significant part of my problem is related to hearing changes that have occurred over the years.
georgehifi's avatar
georgehifi
4,966 posts
 
The Peachtree 220 from what I found can almost double into 4ohm giving 400watt but I can find nothing into 2ohm.
If it gave 600 or 700 into 2ohm then this is the sort of amp that would not whimp out into the 1ohm of the the Ethos.
And at 72 years old you don't want an amp that is going to curtail the upper mid/highs, because it's here where the Ethos are that heavy load of 2 to 1ohm, that will make a whimpy amp sound soft and dull.

Cheers George
steakster
720 posts
 
Here's my 2 cents. Cables and power conditioning. I had stats for years, later monitors. I love the piano. It's much more difficult to reproduce accurately than vocals. I use a certain track on George Winston's close mic'd 'Plains' as a test. Certain notes were like the proverbial fingernails on a chalkboard. And this is on a system with a high end tube preamp and tube monoblocks. After a year and of half of tweaking, I finally discovered what mix allowed it to sparkle. It took a lot of tweaking. Years ago, when I spoke with Bob Crump about his modding process, he said it came down to pain-staking trial and error - and a lot of patience. Agreed. My solution was cables and power conditioning. YMMV.
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