We do have customers that have had Martin Logans and our amps for extended periods- one guy still has the same speakers (CLS2s) and a set of MA-1s built in 1990. So you can use OTLs.
Paul Speltz, who makes the ZEROs, has a letter from Steve McCormick that states that his solid state amps sound better driving 4 ohms through the ZEROs than they do direct, and Steve's amps drive 4 ohms without difficulty.
IOW even solid state amps make more distortion when driving lower impedance loads (this can be seen in the specs of any solid state amp), so the ZEROs can be used to reduce that distortion. Since the ear translates distortion into tonality, the result should be smoother sound. |
Atmasphere, I read your article on the development history but forgot to ask an important question. Would it make sense to try impedance matching with my SS amp first before buying the tube amp to see if that improves my low volume issue? Also, if I plan to use the ZERO might I just as well get an OTL amp? |
Good, I guess my understanding wasn't THAT far off. Based on what I've learned in these discussions, then, I am interested again in trying a tube based power amp with the ZEROs. I will still keep the Peachtree Nova as a preamp for its latitude of source connections and keep the ML's partly because they're new and partly because, having used electrostats for 35+ years, I'm habituated to their sound. The next step will be to decide on an amp. Atmasphere, does it make a difference whether the ZERO unit is located at the amp or speaker end of the cable?...I'm considering using the naked ZERO but, based on cost considerations, it will be awhile before I make these purchases. |
^^It might be, but when you use the 4 ohm tap of most tube amplifiers, the output transformer often has a loss of bandwidth at both extremes and some are better than others. The ZEROs take care of that problem by allowing you to use a higher impedance tap where the transformer is more efficient and the amp makes less distortion.
While fundamentals of instruments don't go that high, harmonics of them certainly do. |
Going back to an earlier discussion where I asked advice regarding the use of tubes with electrostatics, I kind of abandoned the idea because a number of issues arose that were a little involved for me to get comfortable with. One of the main ones of these was the prospect of finding a tube amp with a 2 ohm tap and whether using the ZEROS at the 4 or 8 ohm tap would accomplish the same thing. Based primarily on Atmasphere's explanation I assume that both approaches are viable and equal(?) in their ability to handle these extreme loads. I'm not claiming any kind of complete understanding of the relationship of feedback to distortion or its control, but my gut tells me that the ZERO approach using "normal" taps from the amp would be the better choice, if for no other reason than having greater latitude in choosing an amplifier.
Once again, I find myself in a discussion that exceeds my experience and level of expertise but realize that just because I can't hear anything above about 8000Hz doesn't mean that those frequencies above that level don't contribute to distortion. However, in regard to those "shunt approaching" frequencies described, there are no musical instruments, at least in the base harmonic, that come near 20KHz. If my understanding is correct, then, does this mean that using the 4 ohm tap with the electrostatics may be acceptable at low to moderate volumes? |
^^ No. I don't know of an output transformer that is designed to handle a 0.5 ohm load!
Fortunately this impedance occurs at about 20KHz, so there is not a lot of energy involved. But if you are using a 4 ohm tap on the amp to drive the speaker, the feedback needed to cause the amp to give flat frequency response might be insufficient. The ZERO solves that. |
"However since you have Martin Logans, in order to get a tube amp to play them right, a set of ZEROs (www.zeroimpedance) is advised. This will allow a tube amp to deal with the near-short impedance that occurs at high frequencies in the Martin Logans.
Atmasphere (Threads | Answers | This Thread)"
Don't the output transformers that most tube amps have, do that already? |
You are quite welcome.
Should I point out that tubes have a reputation of doing low level detail better than transistors? The more resolution you have (and ESLs have a lot) the easier it is to hear this.
However since you have Martin Logans, in order to get a tube amp to play them right, a set of ZEROs (www.zeroimpedance) is advised. This will allow a tube amp to deal with the near-short impedance that occurs at high frequencies in the Martin Logans. |
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What a coincidence. I went outside right after I sent my last post to see what a police car was doing on our block and two of my neighbors were out also. I told them the situation and they offered their help to get the bridges down from the entertainment center and I went directly to the task of switching the speaker cables. It did make a difference using the 80W Nova as you suggested it might and I wasn't surprised that your advice worked. However, because I'm not very good at discerning subtle changes, I WAS surprised that I was able to hear it.
I also tried listening at higher volumes (even to the overture from tannhauser) and, possibly, because it wasn't at concert listening levels, it didn't seem substantially lacking in any important way. I know I have more listening to do before making a decision but we've substantiated at least one important issue regarding this power/distortion issue and I thank you once again. |
Well, you may not have enough power at higher volume levels... |
Atmasphere, based on advice provided in my threads and many others of yours that I've read, I'm confident that this will have a good chance for success. I would already done as you suggest, but I'm waiting for help to gain access to the back of my entertainment center. It's large and has two heavy bridges between the 2 towers that I am unable to even assist with. When my 4 grandsons return from a camping trip, maybe I can talk them into doing this "one more time".
What other issues am I likely to run into going from 220 to 80 WPC? Thanks again. |
I appreciate the well considered advice regarding headphones and I do use them occasionally but only to shut out competing activities in our house and to limit my intrusion on others. Even though their sound reproduction is incredibly resolved, it just doesn't sound natural to me as if, like Larryi stated, the sound is originating in my head with no sense of a soundstage. Whatever the reason, even if only psychological, for everyday listening I'll not be using them.
On the other hand, because my stated goal is to acheive better detail at lower volume settings and, as I am very satisfied with my system at moderate to higher volumes, and because chasing it in other ways would be more involved and expensive, it probably makes better sense to develop a bit more flexibility and continue to use them for those described ocassional circumstances.
I've needed to upgrade my headphones anyway so will look into that. I have the Bose noise cancellers which work well for their designed purpose but are not well suited, IMO, for anything like audiophile listening. I also have a set of "fairly" decent on-ear phones that sound OK but don't do a great job of shutting out unwanted environmental sounds.
I have a question, though, regarding length of headphone wire. Although my seating position is only about 14 feet from my amp, the length of wire necessay to reach my location w/o running it across the living room would be about 28 feet. Will this be an issue? |
Broadstone, from the sound of it all you have to do to confirm or deny my theory is to hook up your integrated amp. With less power, you will be pushing it harder and likely not using it in the lower power region. Try it and see if your low level detail is restored. If not then we need to look at other possibilities. |
I agree with Douglas, whether you are concerned with bothering others or you have some hearing problems, phones could be much better than speakers. Although people tend to listen at higher volumes with phones, they are actually quite good for getting clear, articulate sound at lower volume too. Because phones really don't deliver a normal soundstage (it all sounds like it is in your head), hearing issues associated with left-right imbalance become less bothersome--you don't care as much that more sound is on one side because soundstaging is somewhat irrelevant.
I own electrostatic phones, but, I think any kind of phone will work well. |
Consider electrostatic headphones to accommodate your desire to hear the signal well, and to not disturb others.
Check out my review of the Kingsound M-20 tube headphone amp and KS-H3 ESL headphones. This will yield a premium sound on a par with whatever extreme dynamic speaker you wish to name.
Feel free to send me a personal message if you wish. BTW, the combo of Kingsound headphone amp/phones was so good I purchased them following the review. |
Atmasphere, if the Peachtree 220 amp is the cause of this low volume distortion and compromised detail, I'm wondering if using a more efficient speaker might actually exacerbate rather than improve the situation. On the other hand if using a lower wattage amp would also lower the point where this distortion begins maybe this could be another route I could take. In my setup, because I'm using the Peachtree Nova 80WPC integrated amp as the preamp, it would be a simple matter of removing the 220 from the system making the Nova a stand alone amplification source. In doing this, of course, I will lose the EQ setup as well as whatever attributes that the higher powered 220 provides.
I've been looking into speakers to possibly replace the only 6 month old Martin Logans and have thought about trying to buy back my 94dB Jamo Concert 8's. In my research I came across some very impressive reviews of the Grand Tetons and spoke to the owner (Alex Loon) who is apparently very proud of his design. I know almost nothing about Wavetouch and there is no way to audition them but he has a no-questions-asked return policy so I'm giving that some thought. If anyone knows more than what I've been able to find out, I'd appreciate hearing it. |
"The possibility of increased distortion at volume levels below a certain point would never have crossed my mind."
A very easy mistake for any of us. We tend to think of distortion as something unpleasant happening, usually at higher volumes. Distortion is anything that makes the signal stray in a direction further from what's on the recording. So, if your system has less resolution at lower volumes than normal, that's a distortion. |
Ok, I'll try a combined response to these well considered suggestions. As far as trying more sensitive speakers like compression drivers, for example, that will be on my list. As I said earlier, the speakers that I liked best in almost all respects were the Canalis Animas which are not particularly efficient but in my audition of them I was seated no more than 6 feet away. In my home the best were the Jamo Concert 8's which ARE fairly sensitive at 94 dB. I was driving these with a Rogue Audio Sphinx, the same amp which I used with the ML Odysseys which combination seemed not to have the low volume problem that I'm having now.
Once again, Atmasphere, you've introduced another here-to-fore never considered issue. The possibility of increased distortion at volume levels below a certain point would never have crossed my mind. My current amp is the Peachtree Audio 220; I would really like to see what the difference would be if I were able to reinstall the Rogue Audio amp. |
Broadstone, that is true to a certain extent but should not be held as gospel! Generally speaking though, Martin Logan speakers are tricky for any tube amp due to the low impedances of less than 1 ohm at high frequencies. Quite often though they can be solved with a set of ZEROs ( http://www.zeroimpedance.com). |
Would you be considering moving to more efficient speaker; as I would think it would produce the results you are seeking? |
As was mentioned, high quality compression driver systems. More dynamics at low levels, very low distortion. As a very quiet listener (who once in a while does go to moderate levels) I know where you are at. This is the answer. |
Yes, ZD, there are several places for me to do some auditioning and, to a limited extent, I've tried this and is how I ended up buying the Ethos pair several months ago. One of the things that I've been overlooking here is the equalizer, an oversite that might be hard to believe since I spent at least 3 threads extolling the magic of the Behringer DEQ2496. I'll be experimenting to see if I can use it in place of the loudness button of old.
Atmasphere, some of the most important information that I've received on these forums was yours when I was asking for advice regarding the use of tube amps with electrostats. Your description of the current / power relationship in this discussion of tubes versus SS was particularly useful in my understanding this comparison. It also reminds me that, based on these factors, tube amps may be less susceptible to low volume distortion. If my understanding is correct I would guess this to at least possibly be the case. |
This can be an amplifier problem as well. With many amplifiers, the distortion goes down as the output power is reduced- but only to a point. Below that point the distortion starts to go back up.
This occurs at different points with different amplifier designs and also with different power capabilities- the more power the amp can make, the higher the point where the distortion 'turns around' and goes back up.
For example with many amplifiers of about 120-150 watts this point might be at about 5-7 watts- just the point you are using at lower power levels.
With increased distortion comes less detail and a less musical presentation. |
I've been reading some of your posts and am kind of familiar with your situation. What you're asking here may be too subjective of a question to get a good answer. Is it possible for you to audition some equipment first hand in order to gain some type of reference? Just something like Product A was a step in the right direction, but Product B was not. I fear without some type of confirmation as to what it will take to be successful, you'll be doing little more than guessing. Also keep in mind that low level resolution is something that all components contribute to, and not just the speakers. |
Some large panel speakers do seem to play best at moderate volume levels and not quite so well at both extremes of volume. But, that certainly is not the case with all such speakers. The old Quad electrostatics (57s) sound very good at low volume levels. I liked the low level performance of the Martin Logan Quests I owned years ago as well.
If you are looking for the very best low level performance, look at high efficiency full-range drivers and compression driver (horn) systems. I suspect that the reason so many of the giant horn systems that reside in the tiny apartments in Japan have something to do with the ability of such systems to deliver great sound at low volume. |
I am about 10 years behind you, and have heard many fine speakers. I currently own ML's and would not trade them for any comparably priced conventional speaker. sitting a bit closer might help. |
