Magnepan LRS Speaker Review

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Bass response
A few simple considerations about the low frequency reproduction of the LRS. The low-frequency reproduction depends only on the volume of displacement (Vd).

So it's all about estimating the Vd for the LRS speaker. Anyone who has the speaker at home can provide the exact data, I can only give you a rough estimate.

The size of the"woofer panel" corresponds approximately to the marked area in the photo:

This corresponds to about 95cm x 19cm, so about 1800cm².
Of course, not all of the panel surface is membrane surface. My estimate is that about 40% of it is membrane area.
So 720cm² membrane area is available.

Next we have to estimate the "Maximum Linear Excursion (Xmax)" of the membrane. Someone who is better acquainted with the functioning of the Magnepan-Ribbon may correct me here, my estimate would be 0.25 - 1mm excursion.

With assumed 0.5mm Xmax the Vd corresponds to about 720cm² x 0.05cm = 36cm³.
This corresponds somewhat to the Vd of a typical 6'' chassis (10cm³ => 4'', 20cm³ => 5'', 30cm³ => 6'', 80cm³ => 7'', 150cm³ => 8'',...).
Then there are the "losses" due to the open baffle dipol design. This means less bass performance than a "closed box" 6'' chassis.

As already mentioned, owners of the LRS can certainly determine this value more precisely, but it should be clear that for physical reasons alone, not much is possible with the LRS in the low bass.



Multiton Distortion (MD) & decay behavior (CSD)
To be honest, I'm a bit surprised that nobody has determined the multitone distortion of the LRS.
Especially because of the low Xmax of the "Ribbon-Woofer" it would be very interesting to make measurements. Are the intermodulation distortions (IMD) particularly low (minor excursion of the membrane) or high (low Xmax of the membrane)?

The same applies to the decay behaviour of the loudspeaker. The manufacturer even explicitly points out resonance problems, which should be suppressed by setting "buttons" on the panel.
Therefore CSD measurements of the "woofer-panel" and the "tweeter-panel" would be very interesting.

You can easily measure close to the panel with the microphone (preferably at different heights of the panel), which should give useful results in a simple way.

 

[anmpr1]

....and their blatant rip-off of the Apogee speaker trapezoid panel shape...Bob had/has no shame when it comes to marketing....

Umm... how do you 'rip off' a shape? I guess that's the same for Saul Marantz and Jon Dahlquist's loudspeaker--they were 'ripping off' Quad. The numerous preamps that mimicked the Levinson JC-2 form factor to include the same knobs; all those corner horns that looked like a Klipsch, and on and on. Did Acoustat 'rip off' Magneplanar's 'shape'? Or is it just Bob?

 

[Willem]

As for low frequency extension from panels, I recently measured the in (large) room response of my Quad 2805s: they were more or less flat to just below 40 Hz after which response falls off a cliff. This was unequalized, and matches the specification. A few years ago I added a subwoofer and the combined response is now flat down to about 15 Hz (apart from peaks and dips from room modes). Integration was fine once I equalized the sub for room modes and applied a 4th order low pass filter set around 35 Hz if I remember correctly. I think the combination already sounds very good, but I am sure a second sub and Dirac could improve things even further.
I still have my old Quad esl57s and I might measure those as well, but their bass was far weaker.

 

[Vuki]

and why is it completely unlike anything anyone would measure in real life? would you happen to have seen other types of measurements that are better than what amir is showing?

Sure - even amirm's nearfield measurement is much closer to his in-room measurement than Kippel's pir.

 

[Deleted member 2944]

They're definitely not into high-fidelity, though. I wonder how many kooky audiophiles you got in their buyer base that bought them just because of the hype, wanting to be part of the "Maggie club", their unique look and finally maybe their sonic quality on very select material.

The proposition "people having some == they can't sound bad" is preposterous and you should know it.

Another twelve year old. Good golly.

Dave.

 

[josh358]

Wow, what a review.
The whole thing supports the notion of audiophiles listening to their equipment rather than their music
Owners might be attracted to the nuanced design and sound. But, because they are not actually trained well in speaker listening, they get a giant kick out of how "different" the speaker sounds, and laud it as better without understanding it's just their preconceived biases telling them so.

No offense, but you don't have the foggiest notion of what you're talking about. Maggies are noted for their uncanny *realism* with acoustical music, not the other way around.

I would humbly suggest that anyone who hasn't actually heard Maggies refrain from commenting on their sound quality, because there is a distinct pattern here -- those who haven't ever heard the things are critical of them, while those who have actually heard them praise them. Not to put too fine a point on it, anyone who comments on the sound of something he's never heard is making a fool of himself.

 

[peanuts]

No offense, but you don't have the foggiest notion of what you're talking about. Maggies are noted for their uncanny *realism* with acoustical music, not the other way around.

dipole dispersion alone will do that. horns will also sound more natural on some instruments.

 

[DonH56]

I've owned Maggies since 1979 and heard many other dipoles (ESL and conventional). They have their strengths and weaknesses... They sound great on some music, less on others, at least to me. They give you the feeling of being on stage with a small acoustic group, sound ok with rock and pop, generally can't handle big orchestral works (mine did OK, ina treated room and with good subs to back them up). But much depends upon how you set them up and how you treat the room. I started with a smaller model, MG-I and lived with them for quite a while though strayed into other speakers off and on. The MG-I's did great things for some music and in the midrange, but bass was weak, and highs rolled off and beamy. Changing to MG-IIIa's was a major upgrade though still placement-sensitive (nature of the beast) and needed a sub (which I had).

The lower midrange/upper bass peaking has been a part of Magnepan's sound off and on over the years, along with some other "interesting" frequency response choices, but not really much worse or better than a lot of other speakers, particularly smaller ones.

I personally found @amirm's measurements matched very well what I have heard and measured for other Maggies over the years, warts and all. One has to remember the system recreates anechoic measurements, which means no boundary interaction. That means no bass boost and no reflections to "broaden" the image (which I didn't do in my setup anyway -- I usually killed the back wave). The measurements seem to be doing a great job; how they correlate to in-room response is a little trickier for dipole panel IMO.

Given their sensitivity to placement, room, and source music, most any comments on their sound are relevant only to the listener of that particular setup. Most people who heard my setup were very impressed by the sound; some were not, and for some it was "ok".

FWIWFM - Don

 

[AudioTodd]

dipole dispersion alone will do that. horns will also sound more natural on some instruments.

Or based on what particular aspect of the music that a particular listener considers most important in their perception of what sounds “natural.”

 

[tomtoo]

No offense, but you don't have the foggiest notion of what you're talking about. Maggies are noted for their uncanny *realism* with acoustical music, not the other way around.

I would humbly suggest that anyone who hasn't actually heard Maggies refrain from commenting on their sound quality, because there is a distinct pattern here -- those who haven't ever heard the things are critical of them, while those who have actually heard them praise them. Not to put too fine a point on it, anyone who comments on the sound of something he's never heard is making a fool of himself.

Maybe i make a fool out of my self. But looking at the FR and the max. SPL and adding that i enjoy horns. There is just one question that i have about this speakers.
WHERE IS THE BEEF??

 

[josh358]

You're fighting an uphill ideological battle here....arguing for an "in-room/typical use" scenario response test instead of NFS testing...
-- not sure this is the forum for the argument you're trying to make...but you've made some headway!
-- however -- in my opinion, it'd be cool to see in-room measurements, especially with/without room correction, etc., etc....kinda like Amir's testing of Room Perfect and Audyssey... but this scenario would be unworkable for the qty. of products he tests, unless a well heeled audio fanatic would bankroll a facility and staff for such an endeavor???? Any takers? No? Just sayin....

I'm all in favor of every kind of testing, but when we become so in love with the algorithm that we forget to check it against reality, we get into trouble!

Really, there's been some wonderful research on correlating measurements with what we hear. As an engineer, I welcome that -- too often, in audio, we've been flying blind and guessing because the right research into psychoacoustics just hasn't been done.

But we have to be open minded enough to recognize that experimental protocols that are optimized for one kind of loudspeaker may not work for another, and that our current knowledge can probably be refined.

In room measurements don't really need much of a facility -- just a rectangular room of reasonable size. Ideally, it would be an IEC listening room, but it isn't strictly necessary.

I do think that this is more important for dipoles than for conventional boxes, because the former are more dependent on the interaction with the room and more studies have been made of the latter. (There's some excellent literature on line sources, but most of it applies to larger sound reinforcement systems rather than what we use at home. Still, really interesting if anyone is interested.)

 

[AudioTodd]

Maybe i make a fool out of my self. But looking at the FR and the max. SPL and adding that i enjoy horns. There is just one question that i have about this speakers.
WHERE IS THE BEEF??

I’m guessing these would be the musical equivalent of an impossible burger to you!

I love Magnepans but always have another pair of speakers for when their peculiarities don’t match the mood, music or purpose, such as blasting out tunes for a party.

 

[tomtoo]

I’m guessing these would be the musical equivalent of an impossible burger to you!

I love Magnepans but always have another pair of speakers for when their peculiarities don’t match the mood, music or purpose, such as blasting out tunes for a party.

Yeap some kinde of vegie burgers. And people discuss if there is maybe a little touch to much lemongrass in the oatmeal burger bun.No Problem some enjoy but not me.

 

[josh358]

The truth is you have subjective reviews that are varying, just like with any speaker. And just like any speaker, there are pros and cons, a major con would be the horrid vertical performance, where you can’t even slouch or recline without the tonality changing.

Like, not the same technology, but I went with my father to an audio show and in one large room they had the MartinLogan Neoliths, I sat centered with my father to my side, and he asked why only one speaker was playing, we switched seats just to show him what a difference horizontal seating matters with those, which is similar to how important vertical positioning is with these. Another con would be power handling and sensitivity, if I am reading it right, Amir couldn’t get the speaker to measure 86dB at 1kHz for the distortion test, so that means the speaker can’t even handle 10W.

And come on, you are claiming that people are saying the LRS is one of the best speakers in the world? Maybe some people would say that about their higher end models, but those are a different story than this $650 model.

I don't know of anyone who says the LRS is one of the best speakers in the world. By general consensus Magnepan's flagship 30.7 is, but it costs $30,000. What is stunning about the LRS is the sound that you get for $650. I've never heard a $650 speaker that sounds as natural on acoustical recordings and neither, it seems, has anyone else.

I don't think anyone, least of all Magenpan, makes a secret of the fact that these little speakers have limitations. Some of what Amir heard was presumably a consequence of setup -- some of it sounds like common setup pitfalls, and dipoles in general require careful setup -- that's one of their liabilities. But -- and this is what I've heard from people at Magnepan -- the LRS will hit a wall and sound awful if you push the levels too high, and the bass will disappear if you play it in a large room. And there are of course limitations in bass extension, lateral tweeter dispersion, imaging, etc. that are not present in their larger models.

What is stunning is what these do for $650.

(I've noticed by the way that some people have been making the opposite assumption -- that the performance limitations of the LRS apply to the larger models. But of course they don't, which is why there are larger models! Bass extension for example ranges from 60 Hz in the LRS to 20 Hz in the high end 20.7 and 30.7. They're no different than a dynamic speaker line in this regard.)

 

[josh358]

OTOH, Linkwitz pretty much says that dipoles need significant active correction to work through their particular issues. And they cannot be fully charaterised without modelling the room placement, as they are designed from the outset with assumptions about the manner in which they will interact in a room. It isn't enough to simply model the effect of notional reflections from surfaces between the speaker and the listener. In a very real way, the room is forming part of the speaker in a manner it does not with conventional speakers.

Quite. I'd note, though, that part of the design of Maggies and other planar dipoles is that they use *acoustical* dipole equalization. That can't be accomplished with a Linkwitz design, since he has only one driver to work with in each frequency band. But a planar panel can be partitioned into underdamped resonant segments, and these can be tuned to compensate for the 6 dB/octave dipole rolloff. Thus Linkwitz uses active equalization (some of it programmed by Dave Reite in this thread), while Maggies don't require it, as the nearfield measurements show.

 

[MZKM]

I don't know of anyone who says the LRS is one of the best speakers in the world. By general consensus Magnepan's flagship 30.7 is, but it costs $30,000. What is stunning about the LRS is the sound that you get for $650. I've never heard a $650 speaker that sounds as natural on acoustical recordings and neither, it seems, has anyone else.

I don't think anyone, least of all Magenpan, makes a secret of the fact that these little speakers have limitations. Some of what Amir heard was presumably a consequence of setup -- some of it sounds like common setup pitfalls, and dipoles in general require careful setup -- that's one of their liabilities. But -- and this is what I've heard from people at Magnepan -- the LRS will hit a wall and sound awful if you push the levels too high, and the bass will disappear if you play it in a large room. And there are of course limitations in bass extension, lateral tweeter dispersion, imaging, etc. that are not present in their larger models.

What is stunning is what these do for $650.

(I've noticed by the way that some people have been making the opposite assumption -- that the performance limitations of the LRS apply to the larger models. But of course they don't, which is why there are larger models! Bass extension for example ranges from 60 Hz in the LRS to 20 Hz in the high end 20.7 and 30.7. They're no different than a dynamic speaker line in this regard.)

Yeah, I for sure didn’t think they would be $650 when I learnt of them, I would have assumed $1200.

I saw Steve Guttenburg do a video with both these and the Klipsch RP-600M, I didn’t watch it but I assume he gave use cases for each, I wonder how that would change if he used the ELAC DBR62.

 

[josh358]

Not really. The imaging is apparent with a single speaker just as well. Try it.

Testing two speakers will multiply the nightmare of setup with these speakers times two.

Hmmm . . . that hasn't been my experience. When I listen to only one speaker, I lose the wonderful "magic carpet" effect of dipole line sources, the sense that one is listening through a window into a concert hall of realistic proportions.

The MMG had only some of that because it was tilted back and I assume the LRS is the same in that regard, but the LRS still had some remarkable imaging when I heard it at AXPONA.

Spectacular imaging is one of the main reasons people buy dipole line sources.

 

[Boomzilla]

Speakers are measured using a robotic, $100,000 measurement system that scans the speaker in 3-d space and produces full response of the speaker in all directions as if there was no room...

And therein lies the problem. All Magnepan speakers (including the LRS) were never intended to be measured (or listened to) "as if there was no room." The entire design is intended to utilize the room ambience to act in conjunction with the speaker output to provide the intended listening experience. This isn't a point source radiator that was designed in an anechoic chamber. Instead, the front and rear radiation are harmonious parts of the intended listening experience just as much as the room echo contribution is also. You've measured in a way totally opposed to the designers' intent and then made (grossly erroneous) conclusions based on your measurements.

Neither the cost of your test equipment nor the fact of robotic analysis can compensate for your deliberate disregard of the design intent.

 

[richard12511]

I mean - you're doing all this complicated measurements on this ultra expensive Klippel machine to be able to objectively "see" the louspeaker's audio performace and from there predict it's performance in real room (disregarding modes of course). But in this case I see it as complete flop.
"Simple" quasianechoic measurement would much closer predict real room behavior of this loudspeaker.

The listening test confirmed what the measurements showed, though.

 

[richard12511]

No offence, but I find your listening tests as biased as anyone else's.

What about your own listening tests? Do you think those might also be biased?