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As noted in an earlier posting, I am trying out 3.7s, my first time with Maggies, and the dealer has left them at my home for a week. Question for you experts. Does the sweet spot have to be so small? I'm reading about the mysterious 'gunned' maggies and all the things one can do to this range of speakers. Does anything enlarge the area of clearest focus? Gentle feedback from the experienced to a beginner would be useful.
Do I like Maggies? Yes, I think they are pretty amazing. Some of the best sound I've heard.
Dave
Follow Ups:
Stereophile makes a speaker set up disc that is very helpful. The person speaking J G Holt (I believe), actually talks while walking around making it easy to follow and adjust.
I listened with the ribbons on the outside for a very long time. When I finally moved them back to the inside the depth and imaging improved dramatically.
I have mine in a biamp config using an active XO which is a huge improvement over the OEM passive XO.
IMHO, most rooms do not have the depth to place 3+ series far enough away from the front wall cancelling much of the dipoles benefits
Wendell saw your post and emailed to say that if you want a wider sweet spot with the 1.7, 3.7, or 20.7, you should put the tweeters on the outside.
Interesting, my first hand experience shows that I get a bigger sweet spot with the ribbons on the inside. I think the determining factor is the room. Maybe in a different room and or without subs the sweet spot would be bigger with the ribbons on the outside.
There is no absolutes, just an educated guess and then a bunch of trial and error. Josh is correct about the front wall diffusion and 1st side wall reflections .
Jim
Music is the best thing you can do legally that doesn't require a medical prescription!
I suspect it depends on both the room and the crossovers. In the .7's you have first order Butterworth and the lobes will tilt towards the lower frequency drivers, that is, away from the tweeter. If you move off-axis in the other direction, you're right in the null. This will affect both on-axis response and the first reflection, which comes from between the speakers.
In the end, as you say, you just have to try it to see what works with your room, positions, and model.
I get better imaging with tweeters in despite the lobing argument, though I don't have a 1st order bass LP,
The experiments I ran gave similar soundstage width and somewhat less similar depth in a rather wide range of placements of the mid/tweeter panel, and it extends wall to wall pretty much everywhere so long as you do a near equidistant and avoid assymetries, and keeping the tweeters in. The big problem is placing the tweeters near the wall, you need very intensive treatment when putting the tweeters by the wall - they really need to be 2' min away -3' better. The other way round you can get the spacing between the tweeters to 10' without placing the tweeters closer than 2' away from the wall. So long as toe in is not excessive, the bass and mids do ok nearer to the wall.
I think the issue here is sweet spot size rather than soundstage quality. In fact, if I remember correctly, HP didn't like the image of the 3.7's with the tweeters out. There's a description in the review, as it played out in his listening room (not necessarily transferable).
I only have the recliner to get optimal height so I can only comment on image outside the recliner when standing up. So I have less to comment on the size of the sweet spot - but for experiments I did some years ago when I had a 3/4 seater sofa on wheels to play with. Now there is too much junk on it and there is no where to move it anyway.
Recliner sound comfortable. I had one way back when, an ugly green thing I inherited from my grandmother. With a footstool to boot. Great way to listen, if you're as lazy as I am.
Normally I avoid the topic – I settled years ago with tweets outside – I was cleaning and rearranging the equipment other day – when this thread came to mind and propelled me to revisit the subject - on first listen with inside tweets – the impression was one of the soundstage being slightly out of phase – it wasn’t of course.
Magnepan states: “To obtain correct phasing between the tweeter and bass of the MG1.6, the tweeters should be placed on the outside” – I readily heard this - continues listening convinces me that the sweet spot is a tad wider – although the images within the soundstage are softer and not as defined – another observation – when engaging the integrated tube amp the sweet spot opens up a wee bit more – razor sharp images within the soundstage is an absolute requirement in my music.
I'm going to revisit this, too.
Right now, I listen to pole piece side w/ tweets IN.
Does the side you listen to effect (affect?) the lobing? Or the direction thereof?
The way I'm supposed to listen resulted in so much frustration, I had to try something else.
Too much is never enough
"Does the side you listen to effect (affect?) the lobing? Or the direction thereof?"
This is something I don’t lose sleep over – can’t recall this abnormality ever presenting itself as an issue in my space.
The reason I asked....and in exactly that manner is simple curiousity. When I flipped my panels around, just a simple rotation in place, the sound was instantly improved. The sweet spot opened up and i ultimately adjusted the toe to about 11 degrees.
I realized than that the tweeter either led or lagged the bass part of the panel by 90 degrees because of the 1st / 2nd order crossover used.
My theory was that flipped, the sound now back in-phase, since if the bass leads the mid/tweet, the distance it now is further makes the time delay about equal to the listener.
A complicated way to say it simply sounded more 'right'.
I was just curious about the lobing since that in a sense confirms my thought. As a total off-topic note, that is the way phased array radar works. They can steer the beam from a flat emitter by phasing the emission across the panel. You should be able to do the same thing with audio?
I'm glad your setup is set and stable. I owned MG-1s for over 2 decades and a rebuild at WhiteBearLake and never had the kinds of problems with setup the 1.6s gave me....until I flipped 'em.
I'll admit to being over analytical / curious but I always gotta know WHY something works when the change was so.....dramatic.
Too much is never enough
Sure, you can make a phased array with audio, and it's sometimes done, particularly in sound reinforcement applications. A famous example, though it uses analog components and isn't steerable, is the Quad ESL-63, which uses a phased annual ring array to create a spherical wavefront from a planar diaphragm.
One practical difficulty in using a phased array in audio is that the frequency range is so wide that wavelengths range from about half an inch to about fifty feet. To achieve good directionality, a phased array has to be wider than the wavelength that's being steered. So it's easier to steer the highs than the lows.
Another practical difficulty is expense -- to avoid spatial aliasing, you need drivers that are small compared to the shortest wavelength, and even if you use a binary weighting scheme for the size of the drivers you end up with a lot of drivers and channels of amplification, lots of processing power, many DAC's, etc.
There's also the difficulty of getting a given driver to cover a wide enough frequency range.
Both of these factors have made the approach more popular in sound reinforcement than at home.
Even more interesting than phased arrays or arrays with fixed weightings is wave field synthesis, which has the potential to completely recreate a three-dimensional soundfield. Wave field synthesis is already being employed in some soundbars and commercial/experimental installations, but the power of current systems are limited by cost, e.g., the arrays are one rather than two dimensional and of limited size and resolution. A two-dimensional WFS array that covered the front wall might require 1000 or so channels and drivers. It seems to me that planar technology would be ideally suited to such an approach, since the drivers could be printed on a few large membranes. But you'd still need 1000 channels of conversion and low power amplification as well as the processing power to drive them, so it's something that's going to have to be done in LSI by the large consumer electronics companies if it's to become economical for the home. I think we'll move their incrementally, with one-dimensional arrays first, maybe a few to give a coarse approximation of height.
I don't know from the amp crossover side, but as for a driver? IF Graphene works out and you can basically mass batch process sheets of selectively conductive material, that may work.
Of course, wouldn't recordings than be the limit? Some studio stuff sounds flat as it is.
Too much is never enough
Interestingly enough, the same multitrack technology that's destroyed the quality of stereo recordings is exactly what you need for wave field synthesis. All you do is make a dry recording of each instrument or groups of instruments -- multiple recordings if the instrument is directional, like the violin. And you record their position, dynamically if you have to (as in a singer moving around the stage). Then you package the instruments, position data, and the 3-dimensional impulse response of the hall in a file. The reproducing computer can then recreate the hall ambiance and calculate the coefficients for the array, not just to reproduce the 3D field but to manipulate room acoustics, e.g., by suppressing or creating side wall reflections. It would require a lot of DSP to do in real time, but I don't think doing it economically is off the map, anymore than a thousand-channel DAC.
Check out the polystyrene WFS speakers at the bottom of this page:
http://recherche.ircam.fr/equipes/salles/WFS_WEBSITE/Index_wfs_site.htm
Seems to me more sensible to dispense with the separate voice coil!
Satie, it is the very same thing here with the MMGs. The soundstage is just as wide either way but, overall on everything, better with the tweeters inside. (EDIT: oops...using either 1st or 2nd order low pass)The biggest surprise was the soundstage OUTSIDE the speakers. With tweeters inside, it holds better layering. To be sure, this layering is not as good as it is behind the MMGs or in the middle between them.
If the tweeters are outside, this "external layering" vanishes from recordings that display it. The soundstage will still be present beyond the side walls but instruments loose depth differentiation. Intuitively, I would have expected the tweeters on the outside to be the ones that did this. I am still scratching my head on this.
(I should add that this is with the MMGs standing straight. I have not allowed mine to lean back for ages.)
Edits: 02/13/12
Yes, I don't get the lean thing - I keep everything straight with a 90 degree bubble level. Any departure sends the images to the floor or the ceiling.
Yes, there is something wrong with the tweeters out in a loss of image precision, also the images outside the speakers are damaged. Simply miked recordings from the dawn of stereo, more so those of jazz ensembles are astoundingly rich in spatial information and image placement is very convincing with tweeters in. With the tweeters nearing the side walls, this does not work as well.
"...more so those of jazz ensembles are astoundingly rich in spatial information and image placement is very convincing with tweeters in. With the tweeters nearing the side walls, this does not work as well."
LOL, I love the reaction of people who hear some of these old recordings on Maggies for the first time. One of them once said that we had already invented a "better-than-surround" experience but we just did not know it then. I guess recording technology was way ahead of playback capabilities for a long while.
Then, in the 60s and 70s, we often got burned by the multi-miking free-for-all. It took time to realize that "more" was usually not "better" for real stereo.
Interestingly, Blumlein was very aware of the ability of stereo to reproduce depth. I understand it's mentioned in his first patent.
I once saw a demo stereo sound movie Blumlein made back in the 30's at a SMPTE NY section meeting. He walks around the stage talking. It was projected in an ordinary movie theater but not only could you hear his lateral position, you could hear his distance from the mics. Much superior to what we hear today.
I'll bet that was an optical track, not magetic.
Too much is never enough
Yes, I was always impressed by the amount of good audio signal that those optical film tracks could hold.
Like Josh mentions, it must have been a custom rig in those days.
It would have been, they didn't have AC bias then. I don't remember whether he actually did a Dolby-stereo-type side-by-side optical track on the print, or whether he just ran two interlocked optical tracks on dubbers (or built something custom -- I'm not sure when interlocked dubbers came into use).
... as is my custom... Don't forget to set the ribbons parallel with each other. All too easy to overlook after trying a series of moves to find the right room placement. With ribbons it's similar to a heigth adjustment because the acoustic center is about where your ears are perpendicular to the ribbon element.For myself I had noticed that the soundstage wasn't exactly symmetrical between left and right and incorrectly thought it to be beause of the curtains to the right. No. I had forgotten to check it after finding where I was going to place the speakers. The lean of the speakers does not have to off by much to shift the heighth of the image relative to each side. That said... I am planning out some stands and intend to take advantage of that. Attention to detail pays dividends.
Edits: 02/13/12 02/13/12
I have an original stand design with micro-adjustable tilt, if you'd like to discuss it offline.
Too much is never enough
pictureguy, I do appreciate the offer. I have something in mind that I want to try. As to when I'll have the time to do it is the obsticle. Nearly all of my discretionary time just disappeared for the time being. Which is OK. Familly and friends need some attention and they're more important that messing with the rig for now. The upside is I have just about enough time to make carefully considered additions to the library. I'll e-mail you if I depart from the idea though. Thank you.A fellow explorer in audio
Edits: 02/14/12
Get yourself a copy of 'Google Sketchup' and let me know when you want some drawings.
My design philosophy was first and foremost, 'anti bridgework'.
I intentionall took the minimalist approach, not the 'easy' way out.
I believe in design and used a minimum amount of metal. Everything has been rethought.
You won't be disappointed. Tilt is micro-adjustable and can be calibrated in degrees.
.......
Too much is never enough
A useful trick: put on a monophonic recording.
Move your speakers and yourself until you get a solid center image which doesn't move with changing frequency or volume of music.
When you go back to stereo, it will sound very nice.
good advice, and seldom heard! Setting up with Mono is the best way Iv'e come across to 1) check pahes 2) lock in a very good stereo image.
From my experience, locking in a tight Mono image will give a very tight, small Stereo sweet spot. If you want a larger one, try tweeters out, panels angled farther out, etc. Sweet spot will widen at the expense of focus, but this is inherent to the speakers.
Some folks complain Maggies are difficult to set up. I prefer to think of it as a strength by changing position, the image and focus can be modified to your preference. Conventional speakers have no where near as much flexibility.
I don't know that I have ANYTHING in mono!
Maybe I can get iTunes to cooperate?
Too much is never enough
This is all fascinating stuff. Thanks to all who have contributed so far. These speakers have opened my eyes to a new listening experience - and though I'm a Maggie beginner I am 65 and have clocked up 50 of those years with various bits of hifi kit, so I'm not a general beginner. Nice to rethink stuff at my age! Very refreshing. No decision yet though.
Dave
...that I never made an effort to widen the sweet spot. For all the good things that I have achieved in optimizing this MMG setup, this aspect has never received ANY attention.
I can sit right or left of my best listening spot and derive most of the same benefit. Tonally they are almost as enjoyable and most imaging remains outstanding...but the center imaging between the speakers does shift more obviously. Imaging behind the MMGs, surprisingly, shifts less than the center, probably due to my specific layout.
Overall, the sides are still quite enjoyable. In fact, if my wife joins me, she gets the center of the sofa and I get a side. For non-classical music and for TV I get all the goodies I need. Which is to say, this is still far better imaging than most people will get from a sweet spot in other speakers.
For classical or orchestral music, however, I need to own that sweet spot. Thank heavens she doesn't like this kind of music all that much.
My wife doesn't care - flatly doesn't care. She's not as interested in listening to music as I am. When I listen in the living room, she's elsewhere. When I go to the cave, I usually have it all to myself. For the HT stuff, adding the visual information dramatically improves steering anyway, so it's hardly an issue.Regardless, I can listen quite enjoyably from nine different seats - I know because I have. Of course, the setup is all about the front, center seat - as it should be. Sometimes, it's okay to be a narcissist ;-).
---
I must add to the comments regarding placing the tweeters closer - for greatly improved image depth. When I made the switch, I had a flashback from the '80s - sonic holography. Wow! I pretty much follow Magnepan's recommendation regarding toe angle (pictured in their manual). Improving the setup for my selfish enjoyment didn't result in the cry of foul from the individuals who sit elsewhere.
Ultimately, I think they are quite enjoyable from practically anywhere in the room, but they still sound their best from a single vantage point. As listening is typically a solitary activity, that's not a problem for me.
Edits: 02/12/12
Hi Waz, true "sonic holography" it is! Carver may have coined the term but Maggies truly deliver it.However, it is interesting how similar perceptions may mean different things to each person...my wife, in this case. One day I asked her to sit at the sweet spot and tell me where things were in the soundstage. This was to verify what I heard. I played a few pieces. She identified all the elements in positions and layers inside and outside the room as well as behind us, pretty much as I heard things. After a few pieces, it went something like this:
I ask: Where is that conga, dear?
"What, more? I am getting hungry. Ok, outside in the patio, toward the right side."
- right, and the Saxophone?
"Centered, midways behind the TV and the wall."
- right. Just two more to go. On this one, where is the first guitar?
"Right side, between the speaker and the corner."
- right, and the other guitar?
"Centered, midways behind the TV and the wall."
- good, and the audience?
"Most all extends left to right outside in the patio. Some of the whistling comes from close to the ceiling, behind us."
-right. Here's the last one. Where's this band?
"Marching from outside the left wall curving to the patio and ending outside the right wall"Perfect, we're done, I say. Then I add: Isn't this all impressive?
She looks at me kind of puzzled and says: "Huh! Aren't all surrounds systems supposed to do the same?"
Not really dear. In any event, this is not the surround system. It is just the two Maggies.
With her most impassive tone: "Whatever. Are you ordering the pizza now?"
Edits: 02/13/12
my profile has photos. I find ambiently, the sound is still so nice and pleasant: you can walk around your room, they are slender after all (unless your room is small, then nm).
short story: yes, the sweet spot is in that listening seat. in my experience, that is just the deal. I find it a cheap cost for the sound, especially once you get them locked in.
and you will need to get them locked in.
/ optimally proportioned triangles are our friends
You might want to see if the rooze setup would help. That's where the sides or edges of the speakers are pointing at you. The only problem you might have with this is you don't want to kill side wall reflections but try it anyway.
Alan
Good idea, didn't think of that.
I've discovered that Maggies can have multiple sweet spots (OK, I'm stretching the term, but let me explain). First, there is a classical sweet spot (your head in a vice, dead centre). Then, there is the 'all the way to one side' sweet spot. If I sit completely to the side, about three feet to the right of the right speaker, I get a completely different, and often times very surprising presentation of the familiar material. And often times I get delighted upon experiencing the musicality of a certain passage in a completely different way. But just as surprisingly, I somehow still get to 'see' the soundstage?
There is also the magic of hearing Maggies while being in a different room. The sound changes, the presentation changes, you get to hear certain relations between the instruments/vocals that are not all that prominent while listening in the classical sweet spot position.
I encourage you to experiment. Maggies are wonderful in that two speakers can create a 3D holographic presentation that sometimes approaches the multi-channel playback. Also incredible for immersing yourself in a well engineered movie soundtrack...
magiccarpetride, totally matches experience with my modified MMG's. I can, also, listen to them from the side position (while someone takes prime center spot), and have a lot of fun too. And hearing them from the other room - it's like having live band in your house. Especially, if it's something like chamber orchestra or small jazz band, or single player.
I never was able to get much of a solid center image with my stock 1.6's historically, but after having them Gunn'd the sweet spot is huge and easy to focus...at least in my room! I think it has to do with the re-wiring of the panels and the X-O changes, but that's just a guess. PG told me I can look for and focus the sweet spot more "casually", and that's the perfect word. My days of obsessing over this are over...finally!
Prior to PG doing his thing, I found starting close together and moving out a little at a time until you lost the center was a good approach. Now, the further apart they are, the better the center is it seems, within reason of course!
I hope this helps.
Maggies are dipoles, so yes, they're always going to have a somewhat limited sweet spot, because most of the sound radiates front-and-back and less to the sides. The advantages of a dipole radiation pattern include relative immunity from room acoustics and the ability to play music a bit louder without disturbing the neighbors. But a disadvantage is that they're never going to be party speakers that fill the entire room with sound.
That being said, you should be able to get a broad sweet spot in the listening area with the 3.7's, e.g., for people who are sitting side-by-side. The 1/4" ribbon tweeter has very broad dispersion. As with monopole speakers, the width of the stereo sweet spot can be increased by using a center channel. And placement and toe-in will have an effect, you have to experiment because it's different for each room -- you're dealing with not just the direct sound but the reflection from the rear.
I agree w/ josh358. I've owned Magnepans since the late 1970s when the sweet spot could be lost just by moving your head. I actually think the 3.7s are very good in this respect. In my set up at home there is excellent center fill for 2-3 listeners. I've always be a solo listener, no distractions, conversations, focused on the music. I mention this because I think that's the type of listening for which Magnepans excel. To me they aren't about background music or filler for a party, they're about a personal connection with the musical experience. Long way of saying that the sweet spot limitation has never been an issue for me in the 30+ years I've owned Magnepans.
Interesting - this is just how I view music. So (1) it is possible to get a wider sweet spot than the 12 inches I'm getting, and (2) you have 30+ years listening to them. So how did you get the image sorted? Is it simply a matter of patient tweeking of speaker position or are there other tricks?
Dave
Not sure what size room the op is auditioning them in, but the key is to get them in the room and off of the walls and to dampen the rear reflections a bit.
The sweet spot will never be huge, but the reward is that once you find that sweet spot (usually big enough for two), you will be rewarded with a life-size soundstage and an incredible presence of the music not found in most speakers of any size or cost.
Jim
Music is the best thing you can do legally that doesn't require a medical prescription!
The room is 23ft x 16ft by 7ft6". The speakers are about 5ft from the front wall, 2ft from the side walls and about 7ft 6" apart. Width apart is limited by the need to lower a front-projection screen for movies - not present for music of course. Front wall a mixture of 50% hangings and 50% vinyl shelving.Worth noting that the side walls adjacent to the 3.7s are heavily curtained to reduce high frequency reflections - and cut out window light for the HT.
Dave
Edits: 02/10/12
I've found that diffusion to the left and right of center, on the wall behind me can have a huge affect of the imaging depth & width in front. Out of the sweet spot may lose some of the holographic affect, but the tonalit is still quite nice.
"I see sound waves"
That seems to be the favorite room treatment with Maggies, diffusion on the front wall at the first reflection points. The brain uses first reflections to gauge room size. The diffusing panels make the room acoustically larger by delaying the buildup of reflected energy.
I'd try removing the hangings from both front and side walls. They're appropriate for omnis, but not necessarily for dipoles, where the most favored treatment is diffusion at the first reflection point on the front wall. You should get a better sense of both width and depth, and a better balance. You can always add absorption back in if the treble gets too hot.
My 3-ways are in a room only slightly larger than your and I have them ribbons inwards. Slightly toed in and just over 5' off the front wall.
My "sweet spot" is such that 2 people can sit on the couch quite easily.
Regards,
Andy
Andy:
I absolutely agree with moving the ribbons to the inside as this is what I did and it did exactly what you said, 2 people sweetspot. I might add that it also deepened the soundstage a tad bit. I have the ribbons toe-in to where they're hitting my respective shoulders, i.e., left ribbon, left shoulder, right ribbon, right shoulder.
Another key is to have your ears at the center point of the panels or slightly above that...if your ears are too low it affects the soundstage, too low and everything seems like it is above you.
Good luck and I got the feeling that the op will end up keeping them once the placement is figured out.
Jim
Music is the best thing you can do legally that doesn't require a medical prescription!
I ran my IIIas for over 10 years with the perpendiculars to the panels pointing directly at my ears. Then I did some experiments, as I found that the music got more engaging if I leant forward on the couch - so the ribbons were pointing behind my head.
So I made toe-in less - so the perpendiculars from the panels were crossing about 3' behind my head. Yes, that sounded better - but then I found that it still sounded better when I leant forwards - so I now have the ribbons pointing to about 7' behind my head.
According to Josh, this also helps the bass as it puts the bass panels more parallel to the front wall (parallel is best for a dipole). In my case with my 'Frankenpans', I can have the bass panels pretty much flat with the front wall and the ribbon/mid frames pointing 7' behind my head.
But, yes, your ears need to be at the half way point of the drivers (with the panels vertical).
Regards,
Andy
Since you are on the short wall, you can move your seating back 6 ft or so, move the speakers another 2ft or more forward, and increase the distance between them by putting them only 1 ft from the wall (tweeters in) with less toe in. Sweet spot should easily fit 2.
You should be able to move the seating back up to 5-6 ft from the back wall (behind you) and get increased sweet spot width. I am sure you don't want to move that far away from your screen, but it is a tradeoff. You just need to decide what is more important and find your compromise.
My room is 18'W 25'L 13'H...The pans are 13'apart from inside to inside an 12'off the front wall in the center of the room....Big sound great tone...but as for the sound of Magnepans..i am not cuting CDs...thay are not vary forgiving...you better feed them the right sound for you...amps preamps wire...so on ... I only like an have the older maggys with wire not foil...I see some set ups were the pans are setup 6-7'apart i could not live with that but you may...goodluck
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