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
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Broadstone...if your pink noise test is coming exclusively from one speaker when out-of-phase, then you have some major issue in your system.

Testing phase with pink noise phase is a very easy test that even non-audiophiles can identify. When out-of-phase, the sound should come from the individual speakers and not in the center. Anything that happens otherwise, indicates something is seriously wrong. It's not even something debatable or questionnable.

It sounds like you have a channel balance issue (at a minimum). The bias or tubes can be seriously off on one channel versus the other...or you have some other type of EQ or defective component messing things up.

I'll also say that your sources are far below reference level, even if operating correctly. A Shanling CDP, Apple TV, or old Theta will not provide reference level playback...In fact, it won't even be close to reference level.

Nevertheless, the reason I recommend the pink noise test is due exactly to what you noticed. Regardless of how bad your source, it still shouldn't make a pink noise test come only from one channel when out-of-phase.

I hate to be the bearer of bad news, but you have something wrong with your system.

On the flip side, doing the the pink noise test and getting such wacky results was enlightening and will help you at least identify which piece in your system that is defective.
Sorry. me chiming in again. Labtec is right of course about how out of phase pink noise should be presented. Also, to be frank, your system is not exactly state of the art and especially CD from the eighties until about the turn of the century might, when played through it, sometimes sound as you had described.
However, I would suggest, that before you start exchanging gear, I would check at your next visit to the specialist, if you've started to hear one sided. It may not, as Labtec suggests, be just your gear, it may well be your hearing, although age induced hearing difficulties generally lead to loss af hearing in the upper frequencies, not to perceived distortions. But again, I strongly suggest, to clear up this question first with a specialist, before you tear your stereo apart.
"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."

For the in phase test, pink noise coming from the left speaker should sound like its coming from the left speaker. Same thing with the right speaker. Both speakers simultaneously in phase should come from a center image between the speakers, just like a main vocal track.

If both speakers are playing pink noise simultaneously, but out of phase, the should be coming from 1 side. The location is usually somewhere between one of the speakers and the side wall.

If you're still not sure, there is an easier way to do this. First, play a CD you know well and that normally has a strong center vocal image. If you do hear a center vocal image the way its supposed to, that will indicate that you don't have a phase problem. (The type of phase that we are talking about here. There are different kinds of phase related issues.). I recommend you do 1 more test, just so you know what this type of thing sounds like. Go to just 1 of your speakers and reverse the speakers cables position on the binding post. (Put the + speaker cable on the - terminal, and put the - speaker cable on the + terminal.) Now, if you go back to your listening chair and play the same vocal track again, you will then see the vocal image shift to one side.
Something wrong is right. The difference between in phase and out is dramatic; when standing nearly centered in the plane struck from one speaker to the other, the in phase sound is centered and the out of phase sound has the perception stereo but more or less equal in volume left to right. In the out of phase mode as I move away toward my listening position the sound moves incrementally to the right. When I retreat all the way to my listening position the sound seems like it's coming from over my right shoulder. I did these tests with the equalizers bypassed but I'm not confident that their presence in the system may still not be having an effect. Anyway, it's worrisome and apparent that I have a significant problem somewhere but haven't yet figured out where to start looking.

To put to rest the issue of needing a hearing specialist, I've been to 3 audiologists, one of which is a tinnitis specialist. I know what my hearing deficiencies are and have used my audiograms to design base slopes on the EQ's. As I've gone into detail on other threads, I can't wear hearing aids because of the extreme sensitivity of my ear canals. For purposes of this discussion,though, my hearing issues are not dramatic but, typically, exhibiting a nearly equal bilateral drop off beginning at about 4000Hz.

ZD, I've tried exactly what you suggested and got the results that you describe but that was before adding the equalizers. I do believe that one of them (right channel), btw, might have a problem. The next step, then, is to remove them and start the evaluation again. Once I get the issue that I'm working on resolved, it isn't high on my list, but I may be looking for an upgrade to my CD player which I've had for a very long time and continue to be quite happy with.