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Post by Gary Cook on Oct 18, 2016 20:37:48 GMT -5
Maybe I should have collected $1 each from all the people that have asked me over the years why I wouldn't recommend ML speakers to them, would have been quite lucrative.  Cheers Gary |
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Post by AudioHTIT on Oct 18, 2016 20:56:29 GMT -5
And an audio amigo is going to loan me his vintage McIntosh MC250 amp to try. Since the outputs are auto-former coupled, and since they have 4 ohm taps, they should be fine with the ML speakers. I was going to suggest trying a Mac, the 250 should probably work fine, though I'd probably want something newer and with more power. The next generation of amps after the MC250 (starting with the MC2205), were considerably better, and they kept improving. |
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Post by novisnick on Oct 18, 2016 21:43:59 GMT -5
Always wanted to hear an MC250! Just seems that there should be better.
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Post by Boomzilla on Oct 19, 2016 0:19:31 GMT -5
Well, if anyone in proximity to Baton Rouge would like to loan me a newer Mac, I'd be happy to try it! LOL
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Post by Boomzilla on Oct 19, 2016 9:17:24 GMT -5
Hi Mr. Levkoff - Would a Zoebel network make the ML's more amp-friendly? It would seem that if the design included one, far more amps would be usable. This isn't anything I'd want to "after-market engineer" for the speakers, but wouldn't it be an effective way to do away with that impedance dip? A touch of (built into the crossover) equalization would compensate for the frequency roll-off induced by the Zoebel. If that would be a feasible solution, why didn't the manufacturer implement it rather than allow the impedance dip? (a speculation question, I know). But it certainly can't have been a cost issue (on a $10K speaker). Perhaps the manufacturer WANTED to dissuade the use of less expensive amplifiers with their speakers? Thought being that if the customer wanted to spend that much on the speakers, certainly forcing the use of specific amplifiers wouldn't be a significant imposition? But if that were the case, why didn't the manufacturer include a list of "recommended amplifiers?"  |
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Post by novisnick on Oct 19, 2016 10:47:30 GMT -5
True Boomzilla, when I first heard the ML, they were driven with a set of MC2KW amps, McIntosh 2 kilowatt MONOBLOCKs. They sounded devine in the treated demo room! Just not in our budget folks!! Also had a rather narrow sweet spot, but OH! How sweet it was!!! |
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Post by chaosrv on Oct 19, 2016 11:21:14 GMT -5
I have a pair of ML Vistas and drive them with my XPA-1L amps quite nicely. They can dip down to 1.2 ohms at 20 khz.
I am considering picking up a pair of the Montis speakers now that they are being discontinued.
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KeithL
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Post by KeithL on Oct 19, 2016 11:53:17 GMT -5
That's absolutely true. However, the disadvantages of output transformers are such that you don't see many solid state amplifiers with output transformers any more. (Because tubes are high impedance devices, while speakers are not, the exact reverse is true for tube amps; there are VERY few direct drive tube amps.) I'm not so sure that you have that quite right. I doubt that "the vast majority of amps" and AVRs can drive these speakers and here's my reasoning: The 0.6 ohm dip does not suddenly appear at 20KHz, rather the impedance dip likely follows a slope over a certain range of frequencies. I have not seen the impedance slope of this speaker but it is conceivable that at 10KHz (1 octave below 20K) the impedance is too low for most amps to handle, even as it hurtles down to 0.6. Also, when you consider high resolution audio recordings the filters are set to cut off audio at about 48KHz (PCM) to 50KHZ (DSD). This means that there may likely be considerable energy at 20KHz, even if that energy is noise or distortion. Additionally, as an owner of these speakers I would not like to take into consideration every source material that I play on them to determine whether or not there is likely to be 20KHz frequencies present. That to me is ridiculous. If I'm buying a high resolution system it is likely that I have high resolution material to play on it. You may be right. And that may be the reason why ML doesn't publish any impedance curve at all for this speaker. But I AM right that any transformer / autoformer coupled amp will have less problem driving these than a "direct-drive" amplifier. As the frequency goes up, the transformer impedance does too. So the driver tubes / transistors see the transformer impedance AND the speaker impedance in series. As KeithL says - transformers are expensive and can cause distortion - but in the case of the ML speakers, amplifier transformers' impedance is a blessing. |
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Post by KeithL on Oct 19, 2016 12:16:31 GMT -5
There are any number of solutions which would serve to control the impedance... including a simple series resistor or inductor. (I'm told that Acoustat used a series 1 Ohm resistor in many of their electrostatic speakers.) Each would have introduced slight side effects, which could then have been accounted for in the design. I can't really speak for the motivations of Martin Logan's designer. However, most of those solutions, while relatively simple and cheap in and of themselves, would have made the overall design more complex. I have to suspect that they designed the speakers to perform as they wanted using the simplest design possible, and simply didn't choose to spend the extra time (time=money) to make them more amplifier friendly. As you noted, these are expensive speakers, and electrostats are known for being very difficult to drive, so they probably reasoned that anyone willing to pay their price would also be willing to pay the additional price, in terms of convenience, of having to choose very carefully from among a limiter number of generally expensive amplifiers. Electrostatic speakers are actually VERY simple devices.... however, as they say, "the Devil is in the details"..... which can get VERY complicated. This makes some folks less than eager to mess around with a design once they get it working well.... The other thing is that we're NOT talking about "better" or "more expensive" amplifiers.... except in the context that, when designing a "luxury amplifier", you can overbuild in in ways that add a lot to the cost, while providing few if any benefits for more than a very few customers. (You could easily build a cheap amp that would run the M-Ls very well; but it wouldn't work very well with normal speakers; it's designing one that would work well with both that makes the job more complicated.) I suspect it's much the same mentality as with very expensive cars. The fellow who designs the $200k sports car assumes that, if you're willing to pay that much for top performance, you won't mind having to pop down to your local airport to buy gas for it. Incidentally, in the old days, it was generally agreed that the best way to power electrostatic speakers was to use custom-built amplifiers that were designed to run at the voltages they use internally. This way there were no transformers anywhere in the signal chain, and the amp could be optimized for the purely capacitive load an electrostatic panel offers. These amps would ONLY work with electrostatic speakers, and sometimes had to be designed with a certain speaker in mind. However, while you still see amplifiers designed for electrostatic headphones, the market for electrostatic speaker amps was so small that I don't think ANYONE is making them any more; if so, only a very few people. (They used to be more common as very high level DIY projects.) As to why M-L doesn't provide a list of recommended amplifiers, I suspect that's simply a matter of economics.... Because the load presented by their speakers is so unusual, the only way to know for sure whether a given amplifier will work well with them is to try it.... This would mean that they would have to buy or borrow each amplifier they wanted to "qualify" for their list ... And, if the list was too short, then this would discourage audiophiles who had other high end amplifiers that would quite possibly work from considering their speakers. So they settled for "officially" claiming that their speakers will work well with "most amplifiers" - while most serious customers know that the opposite is true. Hi Mr. Levkoff - Would a Zoebel network make the ML's more amp-friendly? It would seem that if the design included one, far more amps would be usable. This isn't anything I'd want to "after-market engineer" for the speakers, but wouldn't it be an effective way to do away with that impedance dip? A touch of (built into the crossover) equalization would compensate for the frequency roll-off induced by the Zoebel. If that would be a feasible solution, why didn't the manufacturer implement it rather than allow the impedance dip? (a speculation question, I know). But it certainly can't have been a cost issue (on a $10K speaker). Perhaps the manufacturer WANTED to dissuade the use of less expensive amplifiers with their speakers? Thought being that if the customer wanted to spend that much on the speakers, certainly forcing the use of specific amplifiers wouldn't be a significant imposition? But if that were the case, why didn't the manufacturer include a list of "recommended amplifiers?" |
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KeithL
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Post by KeithL on Oct 19, 2016 12:23:43 GMT -5
Most of our amps work just fine with most M-L models..... They're just so far outside the normal range that we can't always PROMISE it. In general, though, both with ours and other folks amps, you're probably more likely to be successful with amps that are NOT bridged/balanced. I have a pair of ML Vistas and drive them with my XPA-1L amps quite nicely. They can dip down to 1.2 ohms at 20 khz. I am considering picking up a pair of the Montis speakers now that they are being discontinued. |
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Post by Bonzo on Oct 19, 2016 12:39:17 GMT -5
Hi Mr. Levkoff - Would a Zoebel network make the ML's more amp-friendly? It would seem that if the design included one, far more amps would be usable. This isn't anything I'd want to "after-market engineer" for the speakers, but wouldn't it be an effective way to do away with that impedance dip? A touch of (built into the crossover) equalization would compensate for the frequency roll-off induced by the Zoebel. If that would be a feasible solution, why didn't the manufacturer implement it rather than allow the impedance dip? (a speculation question, I know). But it certainly can't have been a cost issue (on a $10K speaker). Perhaps the manufacturer WANTED to dissuade the use of less expensive amplifiers with their speakers? Thought being that if the customer wanted to spend that much on the speakers, certainly forcing the use of specific amplifiers wouldn't be a significant imposition? But if that were the case, why didn't the manufacturer include a list of "recommended amplifiers?" This has been a Martin Logan gripe of mine from the very first time I heard Martin Logan's at my local store, Audible Elegance in Cincinnati, circa 1998. I asked all kinds of questions at the time and I asked the dealer the exact same thing. If these speakers only run well with certain amps, why doesn't ML recommend said amps then? [Heck, B&W proved it. They got in bed with Rotel and Classe. Why doesn't Martin Logan get in bed with a couple amp companies? They got in bed with Best Buy.] Or, why doesn't ML go into the amp building business? Or, since these speakers vary from model to model on what they do and how hard they are to drive, and since they aren't like normal speakers out there, why doesn't ML just build amps into each speaker, then there will be no worries by anybody? I got every answer in the book as to why my questions were basically stupid and didn't make sense. As if Martin Logan were some divine speaker maker and how dare I question their decisions. I even wrote Martin Logan and got zero response. Since then I've watched / observed / listened / read about Martin Logan, their model changes, decisions, sales techniques, and third party speaker reviews, all from a well kept (no blue kool-aid here) distance. I have not warmed back to them in the slightest, at least not yet. I've even found that I'm not nearly as taken with the sound anymore with their newer models. Either I'm being biased because of my old feelings, I've heard other great speakers since then so I'm not as enamored as I once was, or they just aren't making the truly special products I believe they once made. It's probably some of all 3 things really. But I still say hogwash to them and their answers (or lack there of). And here we are back full circle, now to you asking the same old stupid friggin' questions. Try asking them for yourself and see what reply you get. I'd love to hear it. |
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Post by Bonzo on Oct 19, 2016 12:46:47 GMT -5
You could easily build a cheap amp that would run the M-Ls very well Exactly part of my point in my post above. You just confirmed it. |
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Post by chaosrv on Oct 19, 2016 13:04:03 GMT -5
Worst case scenario I can switch back to my XPA-2. Most of our amps work just fine with most M-L models..... They're just so far outside the normal range that we can't always PROMISE it. In general, though, both with ours and other folks amps, you're probably more likely to be successful with amps that are NOT bridged/balanced. |
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Post by novisnick on Oct 19, 2016 13:41:19 GMT -5
@keithl
So you would or wouldn't recommend a XPR-1 / ML matchup? And why? Thanks
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Post by Boomzilla on Oct 19, 2016 14:18:40 GMT -5
Since ML already offers "hybrid" speakers with self-amplified bass, I'd think that they could (easily) add another built-in amp for the electrostatic panel & then the customer wouldn't need a power amp AT ALL. It would solve multiple problems - No speaker wires needed - No amplifier incompatibilities - Perfect frequency response - Single power cord for the whole speaker / amplifiers combo - Nah - makes FAR too much sense!
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Post by garbulky on Oct 19, 2016 14:27:17 GMT -5
Then the speaker would be a self contained active. Here you dont have the choice of using an amp. It's made for you. You either like that approach or you don't. I like that approach when what I really care about is convenience. But less when I'm spending big bucks on a speaker.
The same reason people shy away from DSP units in their speakers. Some just don't like the fact that their expensive DAC got re-digitized.
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Post by Boomzilla on Oct 19, 2016 14:57:40 GMT -5
But in the case of electrostatic speakers, a self-contained active speaker makes good sense. Otherwise, you pretty much need:
A transformer-coupled amplifier OR
A "super-amp" capable of playing into 0.6 ohm at a HUGE capacitive phase angle
But... Matters not what I think makes good sense - it is what it is.
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Post by garbulky on Oct 19, 2016 15:20:56 GMT -5
Like Keith mentioned most Emotiva amps do play with Martin Logans - like your Aerius. They just can't guarantee the results.
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Post by Boomzilla on Oct 19, 2016 15:58:02 GMT -5
I'll not be taking the risk again, thanks.
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KeithL
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Post by KeithL on Oct 19, 2016 15:58:21 GMT -5
I'm going to go out on a bit of a limb here and say that it wouldn't be my first choice. To be totally honest, I've never heard the XPR-1 fail to sound great with any speaker, but I haven't heard one on Martin Logans. The XPR-1 also isn't really intended to drive a load below 1 Ohm, and certainly not a purely capacitive one. The other thing is that electrostatic speakers aren't designed to play super-loud and the Martin Logans seem to recommend between 200 and 500 watts of amplifier power. With a dynamic loudspeaker, which can handle short peaks with lots of power, more power often translates into better dynamics. However, with an electrostatic speaker, which isn't designed to play that loudly, I thing you'd risk damaging it if you tried to "push harder to get better dynamics". (The transformer on an electrostatic speaker is like the output transformer on a tube amp - it can be damaged if overdriven - and an XPR-1 could put out something like 8 kW into 1 ohm.) I think, if they were my speakers, I'd probably recommend an XPA-2 (or a two-channel XPA Gen3). The power level seems more appropriate, and the non-balanced amp is going to be a lot happier with that unreasonable load. @keithl So you would or wouldn't recommend a XPR-1 / ML matchup? And why? Thanks |
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