Do you have a question for the Magnepan factory?

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josh358

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Re: Do you have a question for the Magnepan factory?
« Reply #80 on: 9 Jan 2012, 11:04 pm »
Hi Troy,

Open baffle subwoofers are a better match for planars because they have the same directional pattern and radiation falloff (1/R instead of 1/R^2) so you can match them throughout the room. Also, IMO, they're better for music than omnis because they don't excite the lateral and vertical room modes. As you point out, the tradeoff is that they don't play as loud or as deep, unless of course you use a lot of them and lots of power. This isn't a major consideration for music unless you're an organ buff, but if you want to go all the way down to 16 for dinosaur footfalls or pedal notes you can always add a sealed super-sub -- just measure the longest dimension in your room, that will give you the lowest room mode, if you go an octave below that and use a high crossover slope an omni won't cause problems as long as you don't try to drive it below its resonance frequency.

One of the advantages of separate subs is that you can position them independently of the speakers, the bass never seems to be best at the same place as the imaging and dipole woofers do best without toe in. Dipole subs should be parallel to the front or side wall, not toed in, since that would excite more room modes. Beyond that, you have to experiment, since it's different for each room and listening position. Mostly, you're going to be sliding them to and from the wall they're parallel to because that's where most of the modes will be. If you slide them so that they're sticking out 90 degrees from and touching the side walls, you'll get boundary reinforcement and more bass, but you could get too much, you have to experiment. One cool trick: if you have them the same distance from the front wall that you're sitting from the rear wall, you'll get partial cancellation of the remaining room modes. I used to do this with my Tympani 1-D's and it works quite well. Keep in mind while you're doing this that phase matters, you'll have to use the phase control as you move them to keep the polarity right and if you don't have continuous phase control position them at half wavelength intervals vis-a-vis the crossover point.

Measurement can really help a lot here, if you can watch what's happening on a computer screen it's a lot easier to find a good position, but a Radio Shack meter will do, it's just a bit more work.

Robin Hood

Re: Do you have a question for the Magnepan factory?
« Reply #81 on: 24 Jan 2012, 10:56 pm »
I called Wendell today to discuss several questions that I had posted on 5 January. The following are either my interpretations of his answers or my answers. I would hope that Wendell or someone else would correct any misinterpretations in these answers.

Mini Maggies with 2 DWM woofers:

1.   Is stereo separated bass more desirable than centered combined bass?
Ans.  Stereo separated bass refers to 2 off-centered DWM woofers.  Centered combined bass refers to 1 centered DWM woofer.  As remarkable the Mini Maggies with a single centered DWM woofer sounds, IMO the analogy is similar to using a single centered subwoofer in a speaker system versus two off -centered subwoofers. The primary difference with this analogy is the fact that subwoofer crossover frequency is much lower, 30-80Hz versus 200-300Hz for the Mini Maggie midrange/tweeter panel.

2.   I'm not sure if centered combined bass is an accurate description, but I assume that the DWM does not provide any stereo separation by itself but tends to blend the separated L+R tweeter/midrange panels together. Is this true?
Ans. The configuration of a single DWM woofer centered between separated L+R midrange/tweeter panels does provide great stereo separation in the normal Mini Maggie speaker system basically due to the separated L+R midrange/tweeter panels. I would assume that there is little difference between feeding a single DWM woofer (without the midrange/tweeter panels) a mono signal to the 2 inputs on the DWM compared to a stereo signal to each DWM input.

3.7 Maggies (or 1.7 or MMG Maggies) with 2 DWM woofers:

3.   If I connect the left full range Maggie and left DWM woofer in parallel from my amp left channel and connect the right full range Maggie and right DWM woofer in parallel from my amp right channel, each channel of my amp will see a 2 Ohm load. Is this a correct interpretation?
Ans. Connecting two 4 Ohm speakers in parallel will result in a 2 Ohm load to the amp.

4.   Since the DWM woofer has inputs for both L+R channels, does that mean that you input the L signal to only one input on the DWM woofer, only one-half of the DWM woofer will be playing? In otherwords, is there any reason, such as for full (rather than partial) speaker output, to feed a split L signal to both amp inputs on the left DWM woofer and feed a split R signal to both amp inputs on the right DWM?
Ans. The DWM woofer has two inputs that are not designated L+R channels. Each input feeds one half of the DWM.  The output of two DWM woofers partially fed is equivalent to a single DWM woofer fully fed. Two DWM woofers fully fed is twice the output of a single DWM woofer fully fed.

5.   If I feed split signals to both amp inputs on the left DWM woofer and the left full range Maggie, is the left channel of my amp seeing a speaker load less than 2 Ohms?
Ans. I would assume the answer is yes if the correct interpretation is connecting three 4 ohm speakers to the left channel of my amp. This assumes the left 3.7 speaker is 4 ohms and each half of the DWM woofer is 4 ohms.

6.   Would it help if both sides of the DWM woofer were connected in series? I’m not sure if this is correctly worded but for the left DWM woofer I mean, connecting the left + speaker output from the amp with a long speaker wire to the left - speaker input on the DWM, then a short speaker wire from left + speaker input on the DWM to the right - speaker input on the DWM, and then a long speaker wire return from the right + speaker input on the DMW to the left – speaker output on the amp. If wired in series wouldn’t the combined sides of the 4 Ohm left DWM woofer be an 8 Ohm  load?
Ans. This question was not asked since I simply do not know the relationship of both halves of the DWM woofer and its internal crossover. Perhaps hooking up an ohm meter on this configuration might answer this question.

7.   What is the best way to hook up 2 DWM woofers with one of the full range Maggies such as the 3.7 or MMGs?
Ans. In parallel, though the desirability of this setup is to smooth out the bass, not add more bass.

8.   Are there any sonic preferences or recommendations for just hookng up just one DWM centered between the full range Maggies?
Ans. None, other than running the Maggies full range.

DWM woofer panels with other planar speakers:

The specifications for the DWM are given as 40-200 Hz but the Maggie DMW manual states “The DWM is a woofer, not a subwoofer. And the superior performance of the DWM, as compared to a subwoofer, is due in part, to extremely wide bandwidth (flat to 5 kHz). The DWM can seamlessly cross over at a higher frequency to any of the limited bandwidth "Maggie" models. However, the higher crossover points require proper time alignment to achieve the most seamless blend between the DWM and the limited bandwidth Magneplanar.”

9. Does the internal crossover limit the DWM to 200 Hz for the Mini Maggie midrange/tweeter panels or is the response of the DWM flat to 5 kHz if no small panel is attached?
Ans. The reference to the extremely wide bandwidth, flat to 5 kHz refers to the woofer response. The internal crossover would limit the DWM to about 250 Hz.


SteveFord

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Re: Do you have a question for the Magnepan factory?
« Reply #82 on: 26 Jan 2012, 02:24 pm »
Thanks for posting that - I gave him a rest as he said that he picked up the creeping crud in Vegas.
The question remains: are you getting a DMW or two?

Robin Hood

Re: Do you have a question for the Magnepan factory?
« Reply #83 on: 26 Jan 2012, 07:12 pm »
I currently have two DWM woofers to play around with. Thus many of my questions were related towards exploring the usage and limits of the DWM in a stereo setup.

SGCSG1

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Re: Do you have a question for the Magnepan factory?
« Reply #84 on: 20 Mar 2012, 11:44 pm »
Where's my 12.7? 

There's 1.7 for people with big rooms and Mini's for people with tiny rooms.

People with medium rooms are stuck with a 15 year old speaker. 

No more discrimination against medium roomers!!!!

SteveFord

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Re: Do you have a question for the Magnepan factory?
« Reply #85 on: 21 Mar 2012, 12:38 am »
Yeah, what gives?
Where's the MMG2?

SteveFord

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Re: Do you have a question for the Magnepan factory?
« Reply #86 on: 21 Mar 2012, 11:46 pm »
I'm afraid that we won't be seeing any trickle down technology for the MG12s as it would raise the cost too close to the 1.7s.
It seems that people jump from MMGs to 1.7s (or larger) and an updated MG12 would end up being dropped due to poor sales performance as the 1.7 wouldn't cost all that much more.
That's not what you wanted to hear but that's the honest answer.

UV88

Re: Do you have a question for the Magnepan factory?
« Reply #87 on: 3 Jun 2012, 10:27 pm »
Hi Steve,

I just purchased a Mini Maggie Sytem last week New from a local dealer...sounds good except for two things:

1)When I place my ears to both left and right Mini tweeter/mid panels, the sound on the right sounds full but the left channel sounds very soft and akin to much reduced midrange, only soft trebly sound/a little midrange playing. But sitting from far field, the imbalance seems less of an issue, but I just cant help but worry my set has some problems, are the left and right channels supposed to sound imbalance? I tried switching cables and DWM inputs, but it's localised to the DWM issue I guess as both treble/mid panels alternate in balance once I switch the cables over so nothing wrong with the panels and yes I ensures proper polarity on both panels and DWM and amp.

2)Occasionally I get that high pitched screechy sound when playing some tracks with lots of treble, does that mean I must must the 1 ohm resistor to both mid/treble panels? Heard using those can cool down the highs but also zap the dynamics out of the Mini Maggies.

Of the two Im more concerned about the channel imbalance issue (I only realized when I put my ears to the panels left vs right, from mid field listening, not so obvious). This make hamper me from realizing the full potential of the Minis if my set is indeed a lemon or it that a phasing issue?

Anyone else has this prob with their mini maggie system?

Cheers
UV

rw@cn

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Re: Do you have a question for the Magnepan factory?
« Reply #88 on: 4 Jun 2012, 12:21 pm »
Sorry to ask, but are you using a mono source signal?

UV88

Re: Do you have a question for the Magnepan factory?
« Reply #89 on: 4 Jun 2012, 03:17 pm »
Nope, running lossless ape/flac files to an Rega DAC and then Rega Brio-R to DWM woofer...anychance the woofer output (hi) is faulty? Are you guys who has the mini getting nice solid mids/treble from both panels? Or one side with mid/treble, the other with just mainly treble and very very soft surround like sound which I just cant call midrange

SteveFord

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Re: Do you have a question for the Magnepan factory?
« Reply #90 on: 4 Jun 2012, 10:19 pm »
UV88,
I wrote to Wendell but he's probably running around at the show right now.
Is this with ALL sources and did you have this problem with other speakers?
Have you tried a different amp and preamp (if possible) to make sure that the problem lies with the speakers?
Finally, how far away is your nearest dealer?
When I heard the Mini Maggie system both channels were operating the same so something is amiss.

Robin Hood

Re: Do you have a question for the Magnepan factory?
« Reply #91 on: 4 Jun 2012, 10:27 pm »
Hi Steve,

I just purchased a Mini Maggie Sytem last week New from a local dealer...sounds good except for two things:

1)When I place my ears to both left and right Mini tweeter/mid panels, the sound on the right sounds full but the left channel sounds very soft and akin to much reduced midrange, only soft trebly sound/a little midrange playing. But sitting from far field, the imbalance seems less of an issue, but I just cant help but worry my set has some problems, are the left and right channels supposed to sound imbalance? I tried switching cables and DWM inputs, but it's localised to the DWM issue I guess as both treble/mid panels alternate in balance once I switch the cables over so nothing wrong with the panels and yes I ensures proper polarity on both panels and DWM and amp.

2)Occasionally I get that high pitched screechy sound when playing some tracks with lots of treble, does that mean I must must the 1 ohm resistor to both mid/treble panels? Heard using those can cool down the highs but also zap the dynamics out of the Mini Maggies.

Of the two Im more concerned about the channel imbalance issue (I only realized when I put my ears to the panels left vs right, from mid field listening, not so obvious). This make hamper me from realizing the full potential of the Minis if my set is indeed a lemon or it that a phasing issue?

Anyone else has this prob with their mini maggie system?

Cheers
UV

I would take the speakers back to the local dealer for replacement. The dealer will confirm if the speaker is defective and take the required action with Magnepan.

The Mini Maggies are such a fantastic speaker system that there should be no doubt in any buyer's mind as to the exemplary sonic performance of the speakers. My advice is to not settle for anything less and I predict that Magnepan would agree.

melomaniac

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Re: Do you have a question for the Magnepan factory?
« Reply #92 on: 4 Jun 2012, 11:29 pm »
UV88,
I wrote to Wendell but he's probably running around at the show right now.

yes, he was in newport beach, demonstrating (all day long!) the two woofers (one in a table, one as a stand) with a center channel and two wall-mounted speakers, the stealth system. nice sound indeed, and after the demo he would ask people to find the woofer... most could only find one (the stand) but didn't identify the location of the other (the side-table). okay, so the room was a bit dark ;-)

SteveFord

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Re: Do you have a question for the Magnepan factory?
« Reply #93 on: 5 Jun 2012, 12:41 am »
Robin Hood,
Eliminate the variables first if possible; it may not be the speakers but if so get a replacement. 
They should sound fantastic.
I wish I had been at the show, the coverage on this site shows some beautiful systems there.  Audio equipment design has really transformed into an artform.
Enough so that I was late to work because I sat around too long drooling over the pictures!

UV88

Re: Do you have a question for the Magnepan factory?
« Reply #94 on: 5 Jun 2012, 05:40 pm »
Thanks guys for the heads up on the mini maggie panel imbalance sound, think it's the DWM woofer unit as amp powering the Mini Maggie channels directly(without connecting to the DWM) sounds good with mids/highs. Courtesy of your suggestion, I have requested my dealer to swap for a new set, otherwise would never know how good these maggies can sound.
Im using just 1 DWM, as a 2.1 master bedroom setup.
Any idea how to correctly (phase and polarity-wise) to hook up another DWM? DO i need 2 separate amps or what? The website doesnt really go into detail with the connection hookups, and Im quite certain a few of us might likely get teh wrong polarity/phasing?? Thanks guys

SteveFord

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Re: Do you have a question for the Magnepan factory?
« Reply #95 on: 5 Jun 2012, 09:41 pm »
If your dealer can't answer that one I'll bet Robin Hood can.

I heard from Wendell and he said to give him a buzz and maybe he can help you out with whatever the deal is over the phone. 
« Last Edit: 6 Jun 2012, 01:09 am by SteveFord »

Robin Hood

Re: Do you have a question for the Magnepan factory?
« Reply #96 on: 6 Jun 2012, 04:29 am »
Thanks guys for the heads up on the mini maggie panel imbalance sound, think it's the DWM woofer unit as amp powering the Mini Maggie channels directly(without connecting to the DWM) sounds good with mids/highs. Courtesy of your suggestion, I have requested my dealer to swap for a new set, otherwise would never know how good these maggies can sound.
Im using just 1 DWM, as a 2.1 master bedroom setup.
Any idea how to correctly (phase and polarity-wise) to hook up another DWM? DO i need 2 separate amps or what? The website doesnt really go into detail with the connection hookups, and Im quite certain a few of us might likely get teh wrong polarity/phasing?? Thanks guys

The info you seek is in the DWM manual and is also on the website.

http://www.magnepan.com/manual_DWM#Phasing

Unless you are using an active or passive crossover that limits the low frequency to roughly 250 Hz, I would be hesitant to directly connect the midrange/tweeter panels to your amp. Hopefully the speaker fuse will blow before any damage to the midrange/tweeter drivers but Magnepan is probably most knowledgeable on what torture these panels can take in non-orthodox applications.

I like using my two DWMs centered between the two midrange/tweeter panels. The two midrange/tweeter panels on speaker stands are connected to one DWM on a speaker stand in the 2.1 configuration you describe. The second DWM is on the floor below the first DWM and is powered with a second amp and controlled with a second volume control. In this configuration both sides of the both DWMs are fully powered and the bass is blended to my preferences. I love the DWM bass and I am not sure if one can ever have too many DWMs if one has the money. In this configuration the two midrange/tweeter panels can 12 feet apart with a wide soundstage since the centered DWM anchors the sound and precludes the loss of any center fill.

Magnepan recommends a different configuration for using two DWMs, where each DWM is adjoining opposite walls on the floor and each DWM connects one midrange/tweeter panel. In the recommended Magnepan configuration only one amp is required, only one-half of each DWM is powered but each DWM gets bass reinforcement from the floor/wall position.

UV88

Re: Do you have a question for the Magnepan factory?
« Reply #97 on: 6 Jun 2012, 08:01 pm »
Thanks a bunch for the info Robin and Steve, I received my replacement set which doesnt have the missing midrange sound from one of the panels but alas, to my disappointment, this replacement new set comes with some hideous cosmetic flaw..see pic...should I just stick with it?

..Magnepan shld have some better QC on cosmetics eventhough sound is of utmost priority..these are by no means economical MMG by any standards IMHO.
« Last Edit: 7 Jun 2012, 02:38 pm by UV88 »

SteveFord

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Re: Do you have a question for the Magnepan factory?
« Reply #98 on: 7 Jun 2012, 12:43 am »
If you're not happy with it call Magnepan is all I can say.
They've always stood behind their product.

TONEPUB

Re: Do you have a question for the Magnepan factory?
« Reply #99 on: 7 Jun 2012, 12:53 am »
Where's my 12.7? 

There's 1.7 for people with big rooms and Mini's for people with tiny rooms.

People with medium rooms are stuck with a 15 year old speaker. 

No more discrimination against medium roomers!!!!

the 1.7 IS a medium room speaker, as is the 3.7   the 20.7 is a large room speaker...