Chuckie, There are some simple mods that can be done to the older backplates that make the speaker a lot easier to drive and sound better. PM me if interested.
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.
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.
108 responses Add your response
The RM-200 increases power as the impedance drops. Roger Modjeski has a significant amount of experience with ESL speakers having appenticed with Harold Beverage and designing his RM-10 for his personal ESL-57s. In addition he has designed a direct drive amp for Acoustat speakers so you can bypass the transformers. I suspect the RM-200 would be able to drive ML speakers. BTW - I use a pair of Atma-Sphere M-60 amps with Quad ESL 57 speakers that dip to 2 ohms in the top end. I do not use an autoformer and the amps has no difficulty driving the load. The sound is heavenly. |
Now that the OP has disengaged from his thread. Get this into ya!! as a bit of wow factor!!!!! Us Ausie's are a mad lot. Just press play. http://www.networka.com/stories/34030/big-wave-surfer-ryan-hipwood-surfs-the-right Cheers George |
Even though I've been active in this hobby for about fifty six years having built my first monaural amps from kits in the mid fiftys, I'm completely aware of my limitations attempting to evaluate deficiencies in my various setups. This is especially the case now that I'm in my seventies with the attendant hearing issues. I do, though, think I know what I want to hear but am evidently limited in the language necessary to relate it. Also, based on some of the comments I receive, I get the impression that my responses to some posts have gone unread which may be understandable in consideration of the length of this thread. Anyway, I'm at a point now where I'm going to disengage from this thread in order to take time digesting the significant amount of information contributed here. |
ZD, I agree. The process to get one's absolute sound is really pretty simple. 1) know what your target/goal is/sounds like 2) Take a shot. Then tweak until you hit the target. Sometimes the target will move but with some experience and lots of exposure and focus to how things really sound, eventually it will stop. You can't reach your goal if you don't know what it is and can't recognize it when you hear it. |
Chuckie, coincidentally, there is a pair for sale here on Audiogon and the price seems reasonable. Right now I'm leaning more toward solid state, partly because of my having had more experience with that technology and partly based on the eye opening discussions here on this thread. Thank you for this info, though; I'll keep your suggestion in mind. |
Beside the tube amp Clio09 came up with Music Reference RM-200, this tube amp also has 1ohm 2ohm 4ohm 8ohm and 16ohm speaker taps, Audio Research VT200, and it has more wattage to start with so volume level may not be as critical as the Music Reference RM-200, I bet there are some more out there as well. http://www.arcdb.ws/VT200/VT200.html Cheers George |
"01-22-15: Mapman Zd, Well, there you go then. I don't doubt it can be done with the right amp and sound very good. I'll keep my eyes open for a chance to hear ML and tube amps myself." OK, but how? If the OP can't listen to live acoustical instruments like a piano, what can be done? At first, we thought the problem may be an issue of timbre. Obviously, that can't be the case because you can't get better timbre than the actual instrument itself. And as a general rule, high end audio strives to reproduce that piano as accurately as possible. Just to be clear, my last post on using tube amps with ML speakers was just to give actual examples that not only is it possible, I've seen ML themselves do it. I'm not saying tubes are the answer here. Given the type of problem the OP has, all the amps I can think of that may somehow address the issue are all solid state. For me personally, I approach a problem by focusing on the end results needed. I love tube gear, but I won't buy something just because it uses tubes. It has to be the right solution, or you just make the problem bigger. So, going back to the problem at hand, what is the end result that we are looking for here? That's where I'm at a loss. If we don't know where we need to end up, and if its achievable, I don't see how we can fix anything. But that's just me. There's a lot of smart people here, so I'm hoping to be proven wrong. |
Hello Broadstone I own NAT SE2SE 211 tube amps and personally these have been an incredible match for my Soundlabs. I feel like screaming from my rooftop how lucky I feel to have FINALLY found the amp that for me makes my babies sing. Now this did not happen overnight. I have owned my Soundlabs since 1999 with no modifications,no new panels and no updated backplate and I can tell you if you get the"right" amp,power cords,interconnects or whatever to make electrostatic speakers sing you won't listen critically anymore. It takes time and it make not happen very soon but don't give up. I really don't think many who own electrostatic speakers have really heard what they can do if "everything" is right. In other words, they just "settle" for the so-called best big name instead of trying to get them to sing correctly. I passionate about my babies because I am transported to another realm. I am not here often because I am "listening" no need to buy anything else or debate. |
I may have started this thread under the false pretext that I have a strong desire to switch from solid state when what I really needed was help with certain specific issues thinking that tubes may be an appropriate path toward that goal. What I'm learning from the resulting discussions, especially in consideration of the range of opinions from experts regarding how best to use tube amplication with ESL's, is that my most practical choice is to stay with solid state. Although my system may not be "state of the art" as was pointed out early on this thread, it is one of the best sounding setups I've had in my home for over 50 years so I'm generally pretty happy. For these other concerns I'm going to reinstall DAC's at my two primary sources, play around some more with the equalizers and worry about upgrading amplification later. |
I think Clio09 came up with the answer if the OP really wants a tube amp, the Music Reference RM-200. In that it has 1ohm or 2ohm speaker taps, there is a proviso though, will it still have the watts to get to a reasonable level when driven off these taps, the wattage goes down the lower the impedance tap is used. Cheers George |
Broadstone, "To answer one question regarding the comparison of live versus recorded music, especially using the piano for reference, we have a piano and, yes, the same notes either recorded or live create the same discomfort. This fact, of course leads me to the conclusion that it is not a component of my system that is the culprit for at least this issue." Looking at the above quote, the one thing that stands out is the fact that you have the same problem when you hear real instruments live. I think there's a very good chance that you will not fix this problem with equipment. Think of the live piano as the best or perfect stereo system there is. There's no where else to go. If you want to continue to listen to music, you may have to go in a non audiophile direction. Maybe just something for low volume background listening, or something similar. I wish that I was able to suggest some better options for you, but I can't. Hopefully, someone else will come up with something. |
"Relatively few ML owners use tube amps I would think. Tube amps have never been in the picture." Actually, that's not true. I've seen many ML systems that were powered by tubes. Here's a few examples. My VAC 30/30 had no problem driving my SL-3's. A good friend of mine is very into vintage gear, and have seen him power his CLS's with many different tube amps, even SET's (I know that's not the perfect match, but I thought it worth mentioning because the amps were very low power.), A dealer I know well sells ML as his main line of speakers and always had them paired with Jadis and Sonic Frontiers tube amps. I was invited to a staff meeting after hours at a B&M store that I did a lot of business with, for a new product demo (Prodigy) with and Gayle Sanders, and he set them up with an ARC VT-100. One of the magazines, TAS I think, put together a recommended system consisting of an ARC VT-50 and the Aerius or SL3 (can't remember as it was a long time ago.). Singer demoed the SL2's with an ARC Classic 60 and CJ 11-A. I could keep going on and on with the examples. But I think pairing ML and tubes is much more common than you think. |
George ... I concur that the impedance and phase angle traces between 3K and 10K Hz look rough. But I suspect an amp will not be asked to deliver tons of power in that spectrum. By contrast, I think the "power region" will be south of 1K Hz and maybe even below that. That is where I'd be focusing attention. The impedance curve in the lower bass goes off the chart. It's almost an open circuit. Are there amps out there that can really drive these beasts. Btw, inserting a Zero would seem to exacerbate the "open circuit" look of the impedance trace in the lower bass. These are tough hombres. |
Can find one, but the Martin Logan Montis looks to be very close and in vintage also. That EPDR looks real bad from 3khz to 10khz being -70degrees to -55 degrees phase angle between those frequencies. http://www.stereophile.com/content/martinlogan-montis-loudspeaker-measurements Cheers George |
Bruce (Bifwynne), +1 to your post just above, and to George's reference to EPDR and his characterization of the S-5 as a challenging load. Regarding the on-going disagreements about the suitability of tube amps for driving Martin-Logans and other electrostatics, perhaps we should just declare an impasse at this point. Also, I would refer those interested to this thread, in which all of the present protagonists, and many other knowledgeable folks as well, argued the same issues over the course of a three-page thread. OK, so much for non-partisanship :-) In that three-page thread I would nominate as the tie-breaking perspective the posts by member Frogman, who as a long-time professional classical and jazz musician, as well as a highly experienced audiophile, unquestionably has one of the most impressive combinations extant of audiophile and musical backgrounds. Best regards, -- Al |
George ... right you are. The capacitive phase angle north of 2K Hz is less of a concern than the negative phase angle below 75 Hz, especially coupled with the low impedance. Yup ... I have a non-techie familiarity with EPDR. Didn't click on your link, but here's a great article on the subject: http://www.stereophile.com/reference/707heavy The bottom line is I'll never know for sure how my amp mates with the S-5s until I arrange a realistic audition. One other positive factor in my favor is that my amp has pretty robust power supply ... 1040 joules. Presumably, ... hopefully, ... that kind of PS muscle can smooth over demands for current in the bass region. But as just stated, I won't know for sure until I plug the S-5s into my rig. |
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. |
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 |
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. |
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. |
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 |
George, your comments fit the classic definition of trolling: https://en.wikipedia.org/wiki/Troll_%28Internet%29 The fact is you have not used a set of ZEROs at your house. If you had, your comments would be in line with that of the experience of hundreds of people that use them. One can only conclude that you have never used them at all or are coincidentally the lone voice in the wilderness- Occam's Razor suggests otherwise. Your use of imitation of my posts as a means of belittling is another example of trolling. The intent behind the text is the issue. As best I can make out, you just want to make me wrong and it gets tiresome, which also seems to be your intent. If you don't want me to accuse you of trolling you will have to stop doing it. So far you have yet to actually show the math that supports that the ZERO does not work or that ESLs have an efficiency curve that is the same as their impedance curve making them an ideal match with transistors. If you can do that then we have a discussion. |
Regarding the Zeros I think the best technical classification for what it does is an (impedance) "adapter". If you need an adapter, you need one. IF you don't, you don't. If gear is matched well to start, you don't. If you do, then using one might produce better or worse results than the alternative case by case. It all depends. Were it me, I would not design my system up front to require any adapters. But there are cases where it might make sense. Like most things there is no 100% right or wrong. The right solution always depends on the problem at hand. |
Also I would add that digital signal processing is a very pwoerful tool but also is a huge variable. What matters most is that it be done right to address the task at hand. There are many ways to to it wrong and only a few ways to do it right. If done right, to meet the goals at hand in each case, the benefits should greatly outweigh any disadvantages of inserting it into the signal path. |
"On the one hand, I am *NOT* thrilled that my DEQX PreMATE is inserted between my linestage and amp. It *IS* an artifact that must have some effect on the signal integrity. But having said that, the sonic benefits of the DEQX far out-weight its sonic detriments." I understand the simple signal path argument and tend to think that way myself but practically one could also argue that everything inserted between the source and speakers has some effect. All that matters is that the good outweigh the bad. It is true that the more integration points for a novice end user to deal with , the more chances that things might not work as well as possible. But with well matched high quality gear all designed by pros in the interest of good/better sound, I would not worry too much. HEck some folks even claim that adding magnets in the right places will spice things up in a positive way. |
Sqlsavior, thanks for the suggestion which is similar to others I received several months ago. The first EQ I tried was a parametric and I had a problem learning to use it. The graphic EQ is a bit simpler to understand and its control parameters are consistent with the kind of control that I thought I needed which is the main reason I chose that route. I've found, though, that the proper setup of either is much more involved than anticipated. |
Bifwynne, yes, I have read your posts and have reviewed the PreMATE as a potential fix worth consideration. I had the same concerns re putting additional components in the stream when I added EQ's to address my hearing issues. It may be an affront to the sensibilities of many audiophiles but the overall improvement to my personal listening enjoyment was significant, sort of like having room sized hearing aids. The PreMATE's price is a bit of a stretch for me, though, so for now I'll just keep it on my list for future consideration. |
Broadstone, you may want to try replacing the DBX graphic EQs with a parametric equalizer - one that acts only on a specific range of frequencies (one sets a mid-point and width, as well as height) and try using it to attenuate the frequency range of your sensitivity/tinnitus. Less stimulus to excite the ringing. I do not know if that is an accepted therapeutic principal, but suspect it might work out better than boosting lost frequencies. |
@Broadstone ... you may have caught some of my posts on another thread about the DEQX product. I mention it here because it may be a worthwhile tool for one to throw into their audio toolkit. On the one hand, I am *NOT* thrilled that my DEQX PreMATE is inserted between my linestage and amp. It *IS* an artifact that must have some effect on the signal integrity. But having said that, the sonic benefits of the DEQX far out-weight its sonic detriments. I mention the DEQX here because it might help smooth out some of the harshness that some say they hear with their ESLs ... heck any speaker. No ... the DEQX will not fix a serious amp/speaker impedance mismatch problem. But it will definitely help make a pair of very good speakers sound much better. Plus, of course, there's the added benefit that the DEQX will correct, or at least mitigate, time incoherence issues with one's speakers. I surmise that ML ESLs are probably time coherent with respect to the acoustic spectrum handled by the STAT panels. But there might be some time incoherence between the woofers and STAT panels. ZERO comments (pun intended) on the benefits (or not) of using ZERO autofomers. Gotta tell ya though ... .5 ohms in the high treble region .... not for my ARC Ref 150. Wouldn't even try it. No sir. Hard to understand how any amp (tube or SS) can even drive a near short. |
Please don't accuse me of trolling on these forums Ralph, it's fact and that's that. I'm just keeping things honest here, in that Autoformers are not the magic bullet that you portray they are. And that your better off saving the $700 odd dollars that they cost and getting the right amp or speakers so things do match up. Autoformers are at their the most advantageous when used with OTL amps on speakers they can't drive, should ring bells on who's doing what, on these forums. Quote: "The most important thing to remember about the Autoformers is: if there is no significant impedance mismatch, then there will be no real benefit to using the Autoformers." I'll add to that not that the reviewer would say it, there will actually be a detriment to the sound if used in the above situation. Cheers George |
I've used electrostatics for over 35 years, all of which except for one pair of Acoustats have been ML (Prodigy, SL3, CLS, Odyssey, now the Ethos) and have been aware of their impedance characteristics for most of that time. However, during much of the early part of that interval I thought that simply adding sufficient power would accommodate potential problems associated with that issue. I also thought, as do many of us undereducated hobbyists, that tube amps are, out of hand, naturally "warmer" than solid state. I was wrong, of course, and have come some distance from that time, discovering, for one thing, that the brightest amp I've ever owned was an integrated tube unit that I almost immediately removed from my system. In reading these posts and doing the research they've inspired, I think now that my original post should have read "Best amp for ESL's" period. I shouldn't have started out assuming that tubes were the only or even my best solution. In the past I've used multiple DAC's to deal with my stated issues and for at least one source, achieved a significant improvement. Now, as if my challenges were not already enough, we're discussing significant issues related to the tube/ESL route that challenge my thinking even more. I think my approach, then, has been somewhat backward; I bought amplification equipment based on good reviews and upgraded my speakers based on my familiarity with a certain technology and expected them to meld into a superior system. Fortunately, for most of my music this turned out to be pretty much the case and resulted in what might be the best setup I've ever put together except for these issues of occasional harshness associated with certain frequencies. Because these problems seem to be primarily a result of my age related hearing deterioration I feel now like I'm chasing my tail looking for some magic in more equipment changes. Anyway, I'm going to reintroduce tube DAC's back into the setup and see if that helps but, whether or not it does, I will still be following this thread and continuing research until I get comfortable with a final decision about equipment choices |
Ralph, please don't assume. I have had a pair in my house that were given to me, and have tried them on different occasions, and have always said with amps and speakers that are a mismatched they can be made to work together, but are just a bandaid fix, until the right amp is used. And instead of spending the $600 odd dollars on them as an interim fix, put the money towards the right amp for the speakers being used, or the other way, change the speakers to suit the amp being used. Without having to purchase autoformers and have them in the way. Cheers George |
George, Its obvious you've not actually heard the ZEROs work. Too bright does not work any better than too dull- both are colorations. The ZEROs are an excellent solution for tube amps that are being asked to drive speakers that they simply would not work with otherwise. I think more have been sold to ARC owners than our amps, FWIW. A lot of people want to use tubes with Martin-Logans to calm them down. |
"If you combine that with an amplifier that can double power as George suggests, the result is brightness" Popycock Ralph, it is the opposite with not only with ML ESL's but others as well and you get dullness with an amp that can't keep "keep it up" current wise. Why then advocate the use the Zero as a bandaid fix with your amps on these sort of speakers when getting the right amp is clearly obvious, even a rare tube amp with output taps of 1ohm 2ohm that Clio posted designed to drive this sort of load. Just listen or read the reviews of ESL's with upper range impedances like the OP's ML Ethos speakers have when driven with amps that "can't get it up" (current wise), dullness or similar are the words used all to often. Cheers George |
The ZERO is not a band-aid. It is a problem solver, and very effective- usually removing coloration rather than adding it. There are many accolades on the zeroimpedance.com website and the product has been around now for nearly 20 years. The issue we are dealing with here is that Martin-Logan recognized that solid state amps dominate the market, and they wanted to be part of that- because it sells more speakers. So they made their impedances extremely low. The problem is that ESLs have the same efficiency at all frequencies. If you combine that with an amplifier that can double power as George suggests, the result is brightness. If the amp can otherwise drive the load but not double power, the tonality will be correct. The ZERO allows this with many tube amps which otherwise would not be able to drive the half-ohm load which is what a Martin-Logan is at 20KHz. Sure, there is not much energy up there, but if you have too much it gets painful. |
Looks like Clio09 may have the right tube amp for the OP's Ethos speakers, should work well either off the 1ohm or 2ohm tap and maybe not sound like a fixed tone control, and only one transformer in the way. And you can see it in the second graph working off the 1ohm tap, only slightly deviates of dead flat when driving the simulated speaker load, maybe it will be a bit worse with the .8ohm of the OP's Ethos. [url]http://www.stereophile.com/content/music-reference-rm-200-mkii-power-amplifier-measurements[/url] Whether or not it will have enough watts off the 1 or 2 ohm tap is another story, this will depend on how loud the OP likes to listen, because the lower the tap impedance the less wattage is available, but higher current and lower output impedance (higher damping factor). Cheers George |
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 |
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. |
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 |
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? |
