Followup-Magnepan 1.7s in a 10x13' dedicated room?


Well I brought the demo MG12s home from the dealer for the weekend and they actually worked very well in my small listening room. Everything I love about Maggies was there with a couple of surprises. First, I ended up with the speakers fairly close to the side walls, though the walls are treated. Second, I obtained the best imaging with the tweeters on the outsides. I assumed they would work better on the insides considering their close proximity to the side walls. The sound stage was wide, deep and well defined. I was able to hear and feel bass in the low 40s, which was another surprise. I give credit for that to the 4 inch thick bass traps I made myself. It's amazing what those have done for a room that literally sucked bass out of the room without them. Some recordings were a little bright, but I think I could remedy that with resistors applied to the tweeters. The dealer didn't supply with resistors to take with me. The MG 12s worked so well in fact that I'm seriously considering the 1.7s. Especially since I hope to be moving to a larger room in the future.
linesource

Showing 7 responses by bombaywalla

I also think it is extremely important with Maggie based systems to address RFI/EMI issues in the entire system. It is my belief that Maggies somehow reveal the high frequency grunge caused by these issues to a greater extent than most other speakers, resulting in high frequency related listener fatigue. This can, I think, sometimes be interpreted by the listener as an overly aggressive top end--too bright. The ribbons, and even the quasi ribbons, are very revealing. If something is wrong in the high frequencies, you are going to hear it.

One probably does need to treat the room for Magneplanar speakers but it's for the wrong reasons - the reason that these speakers appear to have an "overly aggressive top end--too bright" & "The ribbons, and even the quasi ribbons, are very revealing" is that, basically, Magneplanar speakers are not time-coherent speakers.
This is very clear from the measurements Stereophile has published for the MG3.6/R - see Fig 6: step response:
http://www.stereophile.com/content/magnepan-magneplanar-mg36r-loudspeaker-measurements-part-2
and for the MG1.6/QR - see Fig 5: step response. Here even the published text clearly states the speaker is not time-coherent:
http://integracoustics.com/MUG/MUG/reviews/stereophile_mg16qr.htm

Non time-coherent speakers have the (very) bad habit of letting the listener hear the high frequencies before the mids & the mids before the bass. As a result the sonics are tipped towards the high frequencies & you get these sort of comments: "sometimes be interpreted by the listener as an overly aggressive top end--too bright. The ribbons, and even the quasi ribbons, are very revealing".
Making Magneplanar speakers time-coherent would resolve the issue but this has to be done at the design/factory level & not in the listener's room after the fact they are purchased by the user.
07-23-14: Brownsfan
Bombawalla, thanks for sharing this info. I had not heard this idea, and I must admit it makes perfect sense....
Brownsfan, yes, what I'm finding out is that a lot of people are quite unaware (& perhaps even ignorant) about loudspeakers needing to be time-coherent. Time-coherence in loudspeakers ensure non-fatiguing sonics & a very realistic & natural playback of the music.
Time-alignment is just one small aspect of time-coherence in loudspeaker design. Time alignment merely aligns the acoustical centers of the drivers such that the sound from each driver reaches your ear at the same time but does not deal with the phase of the various frequencies that comprise a music signal. So, a time-aligned speaker can distort the phase of the music signal & destroy one's listening pleasure.
You get a time-coherent loudspeaker by using an acoustically insert cabinet, time aligning the drivers & ensuring that the phase of the various frequencies that comprise a music signal is not touched.
We are having a long discussion on this topic right now in the thread "Sloped Baffle".

http://forum.audiogon.com/cgi-bin/fr.pl?cspkr&1403209611&&&/Sloped-baffle

It's got some 195 posts! If you start at the beginning of this thread, I have provided 3 links to prev threads on Audiogon discussing time-coherence in loudspeakers. Plus, as you go thru the thread concentrate on posts by "Royj" - Roy Johnson is the owner/designer of Green Mountain Audio in Colorado Springs & he designs only time-coherent loudspeakers. In this thread he answers questions from other members & clarifies the concept of time-coherence & why it's so important.
There are a few loudspeaker manufacturers that build time-coherent speakers & I think that these people are the smarter ones.....
That's all great, but how does it help him in getting his Magnepan's sounding right?
Zd542
Zd542, I believe the answer to that question is: he cannot! This seems to be mostly in-line with Brownsfan's post where he is suggesting (Mye) stands & if that does not work, then there's nothing else. And, this advice from a user who used Magnepan from 1991 - 2014. what does that tell us?
You are also skeptical of this suggested solution - I think what you wrote makes sense (firing at ceiling rather than at user & reflected sound might be less painful to listen to)
The speaker is inherently flawed by design & will never sound right. The user can treat the walls, toe-in, tilt-back, use stands, upgrade the x-over components quality, etc, etc to reduce the issue but it will never go away & it will never sound right...
If one buys this speaker, that's what one has to live with. Better for the user to buy with his/her eyes wide open rather than be surprised after the purchase like the OP....
07-28-14: Linesource
Where the the conversation from this thread has gone is interesting. Especially interesting is the statement that Magnepans and therefore any large flat panel speakers is flawed due to it's design being physically impossible to be time coherent from the top of the panel all the way to the bottom.
Linesource, I NEVER said that "any large flat panel speakers is flawed due to it's design being physically impossible to be time coherent from the top of the panel all the way to the bottom."
this is a statement YOU are making by taking this huge leap just because Magnepans are a flawed design. Let's be clear about that....
if you go over to the "Sloped Baffle" thread also running in parallel with this thread here in the "Speakers" forum you will see in one of my many posts (which was a reply to Bifwynne's question to recommend time coherent speakers) I wrote that Eminent Tech LFT8b, the Sanders 11C/10C, some Quad ESLs & some older Martin Logans were time coherent. Many of the speakers cited by me in that post were planars.
So, it's very much possible to make a planar time-coherent; just that Magneplanars are not.
Just wanted to ensure that you were not putting words into my mouth.... :-)
Thanks
Bombaywalla, I take it you are not a big fan of Maggies!
Brownsfan, I wouldn't put this strongly. I've heard a couple of Magnepans - one was at a friend's house - I believe it was the MG12 - they were quite narrow & not very tall. He was using an Anthem power amp. It was very nice for vocals but lacked any dynamic drive to get-up & boogie. Another time I heard a MG1.6 at a dealer's place driven by a Musical Fidelity integrated amp & an iPod dock for the front end. Very nice sonics. I enjoyed that brief session. In another room this same dealer had the 20.6 full ranges driven by Rowland Model 10 amps but he was such a stick-in-the-mud & refused to give me a demo because I hadn't set up an appointment!! :(
No, I wouldn't say that I do not like Magnepans but I recognize their severe limitations & their inherent design flaw & decided that I did not want to partake in such a speaker.

.....Magnepans can sound heavenly in the right room with the right ancillaries.....
...Sometimes, the problem is the recording. Some times, the problem is the room. Sometimes, it is the wrong speaker for the room, but would work well in another room.....
Brownsfan, these are exact excuses one has to make when one is dealing with a flawed design loudspeaker. When a loudspeaker is properly designed, it works well in any room & works even better in rooms that are correct for its size & correctly treated. Of course, common-sense has to be exercised - I cannot put a Wilson Maxx into a 10X10X8 room & hope to make it sound its best.

At any rate, this discussion with you is NOT to argue with you or be contentious; rather, it is to point out the loudspeaker design flaw & as a result all the tricks you need play to minimize (but never eliminate) an inherent design flaw. If all you dedicated Magnepan users understood what time-coherence is & what its importance is to music playback, you could go back to Magnepan & demand it from their speakers. The manufacturer will make what his clients ask for/demand lest he should go out of business. In such a case both the Audio industry & the user-base would much better off & maybe the following of Magnepan would grow even more.....
Is it possible to measure time coherence?
Zd542 (Threads | Answers | This Thread)
yes, Zd542 it is very much possible to measure time-coherence. For example, look at Fig 4, Fig 5 of the Quad ESL63 as measured by Stereophile & read the text immediately below Fig 5:
http://www.stereophile.com/content/quad-esl-63-loudspeaker-measurements

I don't know if you remember Meadowlark speakers? The owner/designer was Pat McGinty & he built time-coherent loudspeakers. He wrote a very easy to read article about understanding time-coherence & its importance to music playback thru loudspeakers. Here is the link.

http://www.patmcginty.com/Dbench2.htm

If you don't want to read the full article, take a look at these 3 pages that have animations (hope you have Adobe Flash installed):
http://www.patmcginty.com/Dbench8.htm
http://www.patmcginty.com/Dbench9.htm
http://www.patmcginty.com/Dbench10.htm

These animations should make the importance of time-coherence clear to you.

You'll also note that almost 99% of the speakers in the market have the step-response shown on page 10. And, you can troll the various forums to read all the issues people have with such speakers -
just the right ancilliaries,
just the right recording,
just the right cables,
just the right room size,
just the right recording,
just the right music genre,
just the right toe-in
& the list goes on & on.....
it all goes away once you have time-coherent loudspeakers because the speakers are not further distorting the music signal coming down the pipe from the electronics.
Linesource, no problem! :-)
don't know how the LFT-8b are made to be time-coherent. Same question re. the Quad ESL & the Sanders ESL...
No experience with the LFT-8b personally.