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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.
broadstone
bifwynne
2,206 posts
 
George, I agree with you in principle. But to my knowledge, there are not many tube amps with 2 ohm taps out there ... at least at the quality level of Ralph's Atmasphere or my ARC Ref 150.

I respectively repeat what I said above. Maybe the ZERO artifact is not a perfect fix, but the sonic benefits may well outweigh the sonic costs.
tomcy6's avatar
tomcy6
2,624 posts
 
May I ask how much power you need to produce music above 10khz?

I have a couple of charts that show that the only instrument capable of producing fundamental frequencies above 5khz is a pipe organ. A piccolo's highest fundamental comes in at 4khz, piano 4.5khz, violin 3-4khz and guitar 1khz. It is my understanding that second, third, etc. harmonics are well down in decibels from the fundamentals.

I know that overtones are an important part of music, but as a practical matter, how much power do you need at 20khz?
georgehifi's avatar
georgehifi
10,312 posts
 
Tomcy6

It's not the power, it's trying to maintain a flat frequency response between 20hz to 20khz, amps with weak current delivery will sag with these wild impedances that the OP's ML Ethos speakers have regardless of listening level.

And to try and fix this by putting basically another output transformer between the speaker and the tube amps own output transformer is just a band-aid fix.

It should be the right amp to handle those .8ohm impedances to start with.

Cheers George
tomcy6's avatar
tomcy6
2,624 posts
 
OK. I don't want to complicate the discussion between George and Ralph about power ,voltage and current.

I'm just wondering why an amp that doesn't double down at 4 ohms and again at 2 ohms can't deliver the small amounts of energy needed for a speaker to produce the low sound pressure levels (loudness) of the overtones that occur at 20khz. It seems that speakers would require very low amounts of whatever form of electricity is appropriate, be it called power, volts or current, to reproduce the overtones at 20khz. Does the .5 ohm impedance at 20khz make it just about impossible for an amp to provide energy to a speaker?

Maybe this isn't the time to add this to the discussion, if that's the case, I'll butt out.
georgehifi's avatar
georgehifi
10,312 posts
 
Look at Stereophile tests (12 & 13 posts back)on tube amps into their simulated speaker load, and what happens to the frequency response, and then magnify that many times for the OP's Ethos speaker, as they are more severe than the simulated load.

Here is a Parasound amp that can do current, note how with the same simulated load frequency response this amp hardly differs from just an 8ohm resistive load. Compare it now to the tube one and then multiply the difference by quite a few times, because of the OP's speakers more severe load characteristics.
[url]http://www.stereophile.com/content/parasound-halo-jc-1-monoblock-power-amplifier-measurements[/url]

Cheers George
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