Magnepan LRS Speaker Review

[josh358]

But this would mean that the volume of displacement of the LRS would be much lower than I thought.

Since you know a lot about Magnepan, is there any information from the manufacturer about the Vd of the speakers or panels?

I do have the figures for the diaphragm/magnet spacing, but I'm not sure where they are (it was in an email) and they may consider it proprietary. And of course it varies from model to model as well.

You're right, though, the Vd is lower than one would think. I've discussed with them methods to improve the utilization of the diaphragms, but they're still very speculative at this point. One planar manufacturer has added surrounds to eliminate dishing, and once you eliminate dishing and have something closer to pistonic motion, you can increase Xmax without an unacceptable increase in distortion from the nonlinear motion of the film. There are other possibilities as well -- technology has changed since Jim Winey invented these 50 years ago!

 

[josh358]

So that's a 'no' then, to any scientific evidence of subjective preference that belies their objective deficiencies.

LOL, just as here's no scientific evidence of subjective preference for the putatively non-deficient speakers.

Put those speakers behind a scrim and blind A/B them, and we'll talk. Until then, all I see is hand waving from someone who has never even heard them and doesn't know how the measurements correlate to what we hear, but thinks he does because he knows how they correlate for dynamics.

 

[josh358]

The low frequency measurements of stereophiles should be considered with caution, as they do not contain baffle compensation.

Sure, as I think I've said repeatedly the Stereophile measurements are misleading -- you have to overlay the 6 dB/octave dipole cancellation to get far field response.

John Atkinson should really not present those uncorrected measurements as they confuse the average reader (although he does mention the issue in a note). Surely, no measurement is better than an erroneous one?

 

[Robbo99999]

The point does not change. It only accentuates a single position room mode.
View attachment 83915

This is what an early roll-off in the lows would look like as people interpreted the measurements here
View attachment 83916

Well I think it helps to put the general speakers performance into a more genuine light, as a ridiculously huge 160dB y-axis makes the speaker look quite smooth rather than a dogs dinner! I mean look at this the most recent 'standard' speaker that was reviewed on this site, it's a calming picture of serenity in contrast to these Magnepan's and a fraction of the price, and these aren't even a particularly good example, just the most recently reviewed:

And the Magnepan - a random nightmare sandwich with deficiencies at both ends....palpitation time:

Most people would probably EQ their speaker with a 50dB total spread y-axis, which is also approximately how Amir presents his measurements here too.

 

[Blumlein 88]

LOL, just as here's no scientific evidence of subjective preference for the putatively non-deficient speakers.

Put those speakers behind a scrim and blind A/B them, and we'll talk. Until then, all I see is hand waving from someone who has never even heard them and doesn't know how the measurements correlate to what we hear, but thinks he does because he knows how they correlate for dynamics.

You complain the Klippel measures aren't applicable to actual use in room. The same can be said even more so of JA's measures as the in room result in no way has elevated bass. Nor does it sound that way. You seem to wish away the roll off calling a peak at 400 hz, yet a 400 hz rolloff is exactly what the width of the panel would suggest for a dipole.

 

[bobbooo]

LOL, just as here's no scientific evidence of subjective preference for the putatively non-deficient speakers.

Huh? There's decades of research involving accurate measurements and controlled, double-blind tests by acoustic scientists such as Drs. Floyd Toole and Sean Olive showing this. You however have presented zero scientific evidence whatsoever for your claim that there's something 'magical' about Magnepans that is not captured by standard measurements.

 

[josh358]

You complain the Klippel measures aren't applicable to actual use in room. The same can be said even more so of JA's measures as the in room result in no way has elevated bass. Nor does it sound that way. You seem to wish away the roll off calling a peak at 400 hz, yet a 400 hz rolloff is exactly what the width of the panel would suggest for a dipole.

No, actually, if you look back a few pages in this huge thread you'll see that I posted JA's measurements above the Klippel measurements and pointed out that they were *both* wrong. (Or rather, they're both right, but neither reflects directly what you'll hear in the far field with the speakers on the floor.)

As others (Amir?) have pointed out, the speakers *as measured on a floor* show a peak rather than a bass roll-off -- the midbass is at the same level as the highs. This is still a flaw, it's just a different one.

The speakers use 6 dB/octave acoustical equalization to compensate for dipole cancellation. This equalization can be seen in JA's nearfield measurement, and is why it seems to show rising response in the bass.

 

[josh358]

Huh? There's decades of research involving accurate measurements and controlled, double-blind tests by acoustic scientists such as Drs. Floyd Toole and Sean Olive showing this. You however have presented zero evidence whatsoever for your claim that there's something 'magical' about Magnepans that is not captured by standard measurements.

Oy. Who says it isn't captured by standard measurements? You just don't know how to interpret them. I could ask you, for example, to tell me the differences between how a dipole and monopole excite room modes. Know the answer? I didn't think so. And believe me, I could go on from there.

*This is all present in the measurements.* You just have to know how to interpret them. And yeah, that means knowing a bit more than you'll get from Floyd Toole's wonderful book.

 

[bobbooo]

Oy. Who says it isn't captured by standard measurements?

Err...you did, a couple of hours ago:

But that's precisely it -- they don't capture the magic --- and as I said to Amir when the possibility of a review was first mentioned, that's what I was curious about, why they sound better than they measure.

You're jumping to conclusions about the measurements being insufficient without first scientifically examining whether they do actually sound better than their measurements portray in controlled blind listening.

 

[josh358]

Err...you did, a couple of hours ago:


You're jumping to conclusions about the measurements being insufficient, without scientifically examining whether they do actually sound better in controlled blind listening.

Controlled blind listening would be difficult to arrange even if one had infinite resources, since dipoles have different acoustical and placement requirements than omnis. However, it would certainly be ideal to run such an experiment and it would be informative if someone like Amir did so. In the meantime, since the great majority of loudspeakers, planar or not, have not been subjected to such experiments, we have to rely on measurements and on our ears.

What I find amusing is that several here have presumed to judge speakers that they have never even heard. That seems a darn sight worse than not having conducted a blind A/B comparison! Though I guess there's nothing blinder than never having heard the speaker at all.

 

[josh358]

View attachment 83934

Always glad to see a substantive and informative contribution to a discussion.

 

[Frank Dernie]

For the vast majority of my time as a hifi owner the only way to get even bass in a room was by speaker placement. Room compensation software did not exist and none of the sources could have used it anyway.
IME the in room FR below around 200Hz depends as much on speaker position as the speaker itself.
Nowadays it is possible to plonk a speaker down anywhere and compensate for the peaks it is producing using software.
What you can not do, with any degree of success anyway, is fill in hollows.
Dipole bass speakers are very dependant on room position. Older members may remember the dipole subs Celestion made to go with the SL6 and SL600 around 40 years ago. Their position and orientation in the room were critical to getting even/any bass - Celestion calculated positions and orientations for customers that would work since so few positions did.
It seems to me few people nowadays spend much time positioning speakers properly since they are going to confidently rely on software to correct problems but if the problem is a roll off or hollow in the FR they can not.
What this means IME is that if you have got the speaker in a poor position for bass evenness your bass won't be good, even if you eliminate the boom you will have hollows.

I used to have Apogee Diva panel speakers and they more sensitive to room position that any others I have used. I may still have them if they didn't block out most of the light at the end of my new room. I ended up with conventional speakers again and whilst they were easier to position for even bass getting them in a good position still made a big difference.

 

[josh358]

I mean, you are the one skirting any actual real engagement here and offering up vague protests and ignoring the experiences of people that have had heard and owned maggies and can actually engage with Amir's measurements on a professional level. Amir went out of his way to explain his bass measurements and how in-room response measurements works but that seems to have gone over your head.

I may as well get to the end-point of this discussion.

I fear you have me confused with someone else. Ignoring the experience of people that have had heard and owned Maggies and can engage with Amir's measurements on a professional level? Seriously?

Explanation of in-room response measurements that have gone over my head? Seriously?

If you knew how off-base you are, you'd resign from the universe in shame, LOL. All I can think is that you haven't read through the admittedly voluminous posts here, or that you've confused me with someone else.

 

[Blumlein 88]

I fear you have me confused with someone else. Ignoring the experience of people that have had heard and owned Maggies and can engage with Amir's measurements on a professional level? Seriously?

Explanation of in-room response measurements that have gone over my head? Seriously?

If you knew how off-base you are, you'd resign from the universe in shame, LOL. All I can think is that you haven't read through the admittedly voluminous posts here, or that you've confused me with someone else.

Just going by your posts I'm not so sure you haven't confused yourself with someone else.

Maybe these earlier posts are relevant.

https://www.audiosciencereview.com/...magnepan-lrs-speaker-review.16068/post-519521
https://www.audiosciencereview.com/...magnepan-lrs-speaker-review.16068/post-519620

 

[josh358]

Shame? See post 186. That was a response to you. Real shame should come from bringing in the term magic to this thread.


That said, I must say that this thread is going better than I expected. Remember that Devialet thread???

I read the post. As far as I can tell, Amir didn't appreciate the role of dipole cancellation, and was looking only at the role of floor reflections, as one would with a monopole. This necessarily gives an inaccurate result: dipoles do not behave like monopoles here, because the dipoles lose half their effective baffle area when lifted off the floor, shifting Fequal and increasing dipole cancellation.

There have been actual in-room measurements posted here, and I would refer you to those: if memory serves, they show bass essentially flat down to 100 Hz, then shelved a bit lower down to 60 Hz, plus a peak in the lower midrange -- a flaw, to be sure.

Bottom line: without taking dipole cancellation into account, you cannot successfully transform from a free-field measurement, because you are neglecting the acoustic short circuit at the bottom of the speaker.

 

[Wes]

I wonder how many people have owned Maggies - or small Maggies - and gotten rid of them for a cone based speaker?

 

[Blumlein 88]

I wonder how many people have owned Maggies - or small Maggies - and gotten rid of them for a cone based speaker?

Many, many people.

 

[Blumlein 88]

I read the post. As far as I can tell, Amir didn't appreciate the role of dipole cancellation, and was looking only at the role of floor reflections, as one would with a monopole. This necessarily gives an inaccurate result: dipoles do not behave like monopoles here, because the dipoles lose half their effective baffle area when lifted off the floor, shifting Fequal and increasing dipole cancellation.

There have been actual in-room measurements posted here, and I would refer you to those: if memory serves, they show bass essentially flat down to 100 Hz, then shelved a bit lower down to 60 Hz, plus a peak in the lower midrange -- a flaw, to be sure.

Bottom line: without taking dipole cancellation into account, you cannot successfully transform from a free-field measurement, because you are neglecting the acoustic short circuit at the bottom of the speaker.

The great bulk of the dipole cancellation is around the long dimension across the short width. In this case vertically. The amount saved by having it on the floor isn't sufficient to flatten the result. If the speaker normally laid on its side then you might be onto something.

 

[Sancus]

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.

Chalk me up as another person who doesn't exist then; an owner who is also critical of them. Look, it's obvious by your posts that you're deeply biased in favor of Magnepan. You've even admitted in the past to some level of professional relationship with them. You shouldn't make up these strawmen that "hearing them means you'll praise them". Amir heard them, he didn't praise them. And this review is far from the only time he's heard them.

There's always a wide range of excuses put forward by defenders when you criticize Magnepans. Oh, your room isn't right, oh your placement isn't correct, they're only good with acoustic music, yeah the bass is a terrible mess but just ignore that and enjoy the soundstage.

I agree that they produce an interesting spatial quality to the sound, but the idea that this is inherently "natural" doesn't sit very well with me. Because it is a fixed effect, it's always the same no matter what type of music you're hearing. It's fairly appropriate for orchestral classical, but with a lot of types of music it isn't. The thing is, this method is far from the only method of improving soundstage effects. IMO, properly recorded surround classical does a much better job than any artificial stereo effect. And that's exactly what Magnepans produce. It's a sometimes-pleasant, sometimes-not artificial effect.

Is that effect worth the many issues? It clearly is for some, yes, and that's totally fine! I'm glad that people enjoy these speakers. I also enjoy them sometimes! Just not all the time. They are a very poor generalist speaker and that contributes to their other issues to make them pretty impractical.

Personally, this review makes me curious to see reviews of other dipoles, like MartinLogans and especially the Linkwitz LX-521. But also larger Magnepans too, though I don't know if it's possible to fit the 65" tall 1.7i in Amir's setup, let alone the 71" 3.7.

 

[josh358]

I wonder how many people have owned Maggies - or small Maggies - and gotten rid of them for a cone based speaker?

Many have gone in both directions. They're different different speakers and people typically go through several kinds of speaker over the years, often depending on circumstance. I have one friend who owns a pair of Maggies -- 3.7i -- and a pair of dynamics, and knows he should sell one, but can't make up his mind! One is better in some regards, the other in other regards.