[MGbert]

Had an interesting listening session in my shed this past Monday.
Contributors Pansixt and jarcher made the trip from the DC suburbs to
the wilds of Western Maryland to audition my Gunned MMGs.  This turned even
more interesting when I realized that we had different philosophies of
setting up a music reproduction system, so we (OK, I) figured the results could
be of some interest here.

To start with: yes, I did say "shed".  My listening room is an 11 foot
by 11 foot 4 inch space carved out of a nominally 20 foot by 12 foot
climate controlled outbuilding which also doubles as storage. I treated
this as an engineering challenge (hey, I'm a structural engineer)  to
get planars to sound good in such a small space... and with a minimal
investment into equipment.  Except for having my MMGs Gunned, everything
else in the signal path could be considered inexpensive if not bargain
basement compared to other systems here.   I have posted before about my
experiments with First Reflection Traps (FRTs), but this was the first
time other contributors got to hear it.  In addition, room modes in such
a small space demand (imo) equalization to ensure reasonable linearity
of response, which some here would frown on, to say the least. 
Ditto the fact that it is all digital, since my turntable is currently
kaput. 

So here is a summary of my system:

Belkin PF-60 Power Conditioner;
Western Digital 1 TB USB hard drive with WAV files of ripped Red Book CDs;
Oppo BDP-103 (music server and CD transport);
Blue Jeans Cable LC-1 and S/PDIF optical and coaxial interconnects;
Behringer DEQ-2496 Ultracurve (everything but the kitchen sink) DSP,
used as a room EQ, balance control, stereo/mono selector, and DAC;
Behringer ECM-1000 measurement microphone;
Luminous Audio Axiom II Passive preamp;
(2) Apt-1 power amplifiers (circa 1981) each bridged to mono; over 200
watts/channel into 4 ohms;
2 strand twisted 26 AWG Rat Shack magwire as 6 foot long speaker cables;
Magnestand modded Magnepan MMG speakers (aka "Gunned");
Luann panels and pipe insulation for FRTs;
Tall mirror (don't laugh - essential in a small room for ensuring
control of pesky early reflections);
...and not a single tube anywhere in the signal path.

Once I got the room placement/FRTs "tuned" I felt that my system could
hold its own with significantly costlier systems, but who would just
take my word for it?  A lot of my system's performance comes from
careful trial-and-error in speaker placement, FRT experiments, and
learning how to use that blasted Behringer efficaciously.  Better
components, I think, would only give incremental improvements, which
I'll test once my new Parasound Zdac (just came in!) burns in. 

Prior to coming over, I think it's safe to say that the use of a DSP
unit like the Behringer would not be something either Pansixt and
jarcher would have espoused.  More like using speaker cables and tube
rolling, perhaps.  So how did it pan out?  I'll let them speak for
themselves, but  spoiler alert: when I turned off the DSP functions of
the Behringer and then asked if they'd like it kept that way, in unison
they said "Turn it back on!". 

I definitely will encourage discussion on this, but in all fairness
let's give Pansixt and jarcher a chance to post their observations
first.  And in case you're wondering about how impartial they'll be - I
did entice them over with the promise of pizza, but then asked them to
chip in.  So hopefully that takes care of any bribery charges if they say something complimentary! 

MGbert

[jarcher]

I'd just like to preface things by saying I learned a lot more through this experience than just what I went into it for : i.e. hearing gunned MMG's to consider vs regular MMGs and other Magnepans I've heard. And secondly, drawing conclusions which I think will have more universal consequences , and potentially have more universal interest to the AC topic reader than just commentary on one particular system.  So if curious, read on:

What Marc's been able to achieve sound quality wise with his system is frankly a personal triumph in the face of most all challenges imaginable to an audiophile. For starters the net sum worth of all of his components is likely not much more than just the Gunn modification to the MMGs.  He's set up his listening room in a SHED - and the square end at that.  Someone less charitable stumbling on, but not actually hearing the system, and perhaps less charitable than me, would say the situation seems laughable.  And yet the results were as good or better than 90% of the systems I've heard - and I'm leaving that last 10% out to be conservative.  The fact that he's been able to do what he has is all the more impressive because as he noted, he's not an electrical or acoustic engineer, but a structural engineer.  That is, there's no modifying gear or even a soldering iron in sight (I make exception for the MMG Gunn mod, which was not his doing).  Instead Marc has simply used the tools at hand, and logically and systematically combined logic with trial and error to make the very best with what he's got.   

To a substantial degree I attribute those results to his judicious use of the Behringer 2496 DSP doodad.  I really have to eat my hat on this one as even very recently I was slamming digital EQ and suggesting just here on AC that people avoid these devices.  That is, that these devices did "violence" to the original signal, particularly if or when they were used between a preamp and amp and doing analog to digital then back to analog conversion.  Of this latter point I'm still clinging to until I experience evidence to the contrary, but in Marc's case where he's using it between a transport or media server (the Oppo 103) and a DAC (up to recently the one in the Behringer, and now the Parasound ZDAC) makes a great deal of sense.  That is, all is being kept in the digital domain until the final analog conversion.  The fact that a tool such as the behringer 2496 has such power and resolution to handle that without seriously messing up the sound in the process is a testament to how much better (and cheaper) this kind of digital gear has become. 

But it would all mean nothing without someone like Marc at the controls.  In his capable hands he was able to master his stated sonic goal : maximum level frequency response with a detailed and dynamic sound.  In this respect I could find absolutely no fault with his system.  That the gunned MMG's were capable of a surprisingly wide and linear frequency response, down to a very substantial, defined, and deep bass.  I suppose some out there might want argue for even more lower frequency extension, but honestly in the variety of tracks we demoed I never felt wanting in that department.  Like most Maggie owners, I'm will to trade off very deepest LF extension for quality (and if I must have the former, to turn on the subwoofer). 

For those of you wondering if / when I'll ever get to commenting on the gunned MMG's, the purported reason for my visit, here's my (to me) surprising conclusion : I think ultimately what Marc's been able to achieve with the behringer as well as other factors such as speaker placement and acoustic treatment has been more relevant to the sound quality improvement than having his MMG's gunned.  At one point on an admittedly less than perfect track of Joe Cocker's live "Feelin' Alright" he turned off the behringer.  The sound immediately became more thick and less defined.  Some could consider it more "warm" : and with that somewhat shrill track, a perhaps welcome change, but no honest listener could consider it a better result. It had me wondering whether the gunn mod may not perhaps make the MMG even warmer and produce a greater mid-range emphasis, where after all our hearing is most sensitive.  Or perhaps this may have just been the result of room interactions that Marc had been able to EQ out with the Behringer.  Ultimately I don't really know and can't judge the performance of the Gunn modification on the MMG, particularly not based on just one track playing them without equalization.  I'll let Marc comment on that as he ultimately has the most experience.  I think he felt there was substantial improvement in the bass quality (extension & mostly definition) and perhaps greater overall transparency (which may be due to some grill removal and / or the frame). 

But as we are all tempted to jump to conclusions, and furthermore because mod's must be considered in the light of other competing alternatives, I'll come out and say this : in the context of a very small room I can see the MMG Gunn mod being worth it, unless something like the "Super MMG" supersedes it.  For anyone else with even a more modest sized room (say 13 x 15 or larger), I'd have to say go for the 1.7's, particularly now as they are available used for less than $1500.  There is one thing that an MMG panel, no matter how worked on or in what frame / crossover you add it to can do, and this is provide the "scale" that the panels of the larger models can do.  That's just physics.  And I think the new all QR midrange / bass panels helps to overcome some of the sonic difference as well, mainly in detail and dynamics.  Lastly there is the cosmetic issue as well, as subjective as that is.  For me I more often veer more towards the "hi-tech / modern" look vs the earlier arts + crafts wood look.  I.e. on cosmetics alone I like the 2001 monolith look of a 1.7 more than say a Legacy speaker.  Again : very subjective.

To wrap up the critique of the system : again a 9/10, particularly given the constraints of the listening environment and modest gear.  That 1/10 that I felt personally lacking was a bit more refinement / grain reduction, which I attribute potentially to the DA conversion (some of which hopefully will be improved w/ the addition of the Parasound ZDac, though the internal DAC of the behringer was better than I expected).  I suppose one could also argue for more soundstage depth (width and definition otherwise being excellent). 

Marc touched on his header about cabling & tubes.  Ironically I still think some of that could address the immediately preceding points.  Mainly that it's been my experience that certain well designed power cables do have a line filtration effect - even when used with power conditioners on the other end - and that tubes often have the effect of adding soundstage depth - however "artificial" that effect maybe considered by some.  Tube also have at a minimum the welcome benefit of warming & toning down overly bright and poorly recorded mainstream recordings.  On the other hand I recognize, now more than ever, that to a large degree these benefits can be achieved by the expert use of a tool such as his behringer.  So ultimately experimenting with power cabling and perhaps tube "buffering" could be a useful tweak, but the return on investment may not be as substantial for him.

Which brings me to my final point : many of us go about haphazardly trying to improve or change our sound quality by throwing money at it, including through tube rolling and cabling, mainly using these as a form of tone control.  Marc is a good example of probably the better and more effective (cost & sound quality wise) way to approach the issue, which is through equalization, speaker placement, and acoustic treatment.

Marc : kudos to you buddy.  If the furlough get worse, I see you could have a bright future in "system optimization" for audiophiles.  Too bad there are seemingly fewer of us around, and those that are, more hidebound in their advancing age. 

Or additionally, given that a new good sized and well built on-site wooden shed can be had for just a few grand : I could even see a business model in "audiophile cottages". What suburbanite not weary from tiring and / or brain numbing work wouldn't welcome retiring from that & domestic irritation to the bliss of a personalized, customized and isolated listening environment!  With your skills I could see it going for less, gear included, than what many audiophiles pay for just one component.  And just think : when you move you can have the whole damn thing put on a flat bed & carted off and placed in the backyard of your new home.  No starting over or WAF to ever concern you again!  We can only dream.

[jarcher]

PS : Marc - it's a shame given all that nice vinyl you have not to have something functional to play it on.  I have an older Kenwood 3055 (with the "synthetic marble / "kenwoodium" base) mated w/ a Sumiko Pearl cartridge that you're welcome to on extended loan.  It's part of a bed room system and hasn't gotten any use in many months, and may still not, so I'd prefer to see someone get some use out of it.  PM me if interested and we can work out a hand-over (e.g. if you're going to CAF or will otherwise be down this way).

[pansixt]

Wow. Great review. I could just say Ditto, and be done with it. 

I was motivated to make this relatively local though relaxing trip to Marc's Western Maryland Haven by his invitation which I received after I posted a comment about a possible future "Gunn" mod to my MMG's.
My main motivation was auditioning the modded planars and meeting a fellow hobbyist though I guess the promise of a good local pizza was also a draw of sorts.

Not much forethought was given to his system or listening environment, of which I knew little, though I was confident it would
be more than adequate to preview the speakers.
There was a mention of some room treatment. At that point I had no idea how understated that would turn out to be.

During the tour of Marc's Historic Home in the Historic Town in which he and his family reside, I kept wondering where
the system would fit in here considering the basement was actually a cellar with a solid wood pull up door and I didn't think
much would fit in the upstairs loft area. We were then directed outside to his Shed which he has converted, (though that word
can't begin to do justice to the amount of time and work involved), to a listening room where we found a very attractive pair of 
the famed Peter Gunn Modded MMG's elevated close to a foot off of the ground focused on a single seat located extremely near field with a modest flat panel monitor between them. The rest of his system was near by, as it had to be in the fairly small structure.

Now, as far as my intended 'Judging" the Peter Gunn MMG Mod. As it turns out I have more questions than I had before.
And the only way I could answer any of those questions would be to cart my stock MMG's out to Marc's to do a comparison.
Not out of the realm of possibility and would be fun. And maybe bring something Tubed as well. So something to think about.

As for the "Gunned" MMG's, they have a very impressive sound. And I agree with jarcher that Marc's efforts in setting up the room and his system are what is ultimately responsible for them reproducing the tracks we heard so faithfully.
And faithfully they did, as far as the tracks I was familiar with were concerned. The depth on some recordings was simply astonishing. I am not sure I have ever heard so clearly the position of the performers or the staging that came from the MMG's.
The strong Bass was very clean and immediate and very unlike what most MMG reviews claim, and the drums were definitely immediate and so real that they were in the building with us. The rest of the music matched with the typical Maggie transparency and realism.

I don't know how much of a factor was the digital EQ work or the First Reflection Traps but we did opt for the EQ when presented without it. And I was as surprised as jarcher was with that conclusion. As for the FRT Traps, I might try a simple DIY experiment in my room. Easy and cheap enough to do but clearly an aid in Marc's room..

Now would I consider the Peter Gunn Mod if he continues this in the future which is not all that certain past this fall by his own admission?
First, I would have to do a side by side with mine and Marc's. Second, I would have to know my room wouldn't fit 1.7's ever.
And though I will have to move before long, I don't foresee having that small of a listening room.
For now I'm just going to play with placement and a little room taming and enjoy the music.

Thanks Marc

[SteveFord]

No pictures? 

[pansixt]

You've already seen and heard the planars. But we did screw the pooch by not taking any pictures. My iPhone was in the car with a dead battery. I don't remember what jarcher's excuse was.

[SteveFord]

I'm interested in the set up.
Perhaps a Keith Jarrett fan could swing by with their cell phone?

[jarcher]

I was living the moment too much to whip out my camera phone, so will have to rely on Marc to do the honors. 

Though we didn't listen to any KJ, I'm sure he would have approved. We took care of all of our coughing before going in the shed.

[MGbert]

I was living the moment too much to whip out my camera phone, so will have to rely on Marc to do the honors. 

Though we didn't listen to any KJ, I'm sure he would have approved. We took care of all of our coughing before going in the shed.

Ha Ha!    I attended a KJ concert at the Kennedy Center years ago where he stopped and said "OK, everyone, COUGH!" 

I do have a sizable KJ collection, and if my turntable were functioning I would have loved to put him on.  Unfortunately, I find the ECM CDs to be bright and a bit harsh.  On vinyl, though, he sounds sublime.

MGbert

[thunderbrick]

I'm interested in the set up.
Perhaps a Keith Jarrett fan could swing by with their cell phone?

 

[MGbert]

   <blushing>

Guys, you're too kind!  My intent in all this was kind of a "if I can do it, anyone can".  If you're willing to invest the trial and error, room placement is, in my book, the single most effective tweak you can give otherwise good equipment.  Doesn't even have to be great equipment.   

Concerning the Magnestand MMG mod:  in Steve Ford's house, they sounded like his stock 1.7's younger brother, not quite able to fill his 16' X 50' upstairs room as convincingly as the 1.7's (the MMGs beamed a little at the same volume) but otherwise a near dead ringer as far as tonal balance was concerned.  In my shed, the Magnestand haxe a lot more midrange energy than the stock MMGs did before being modded.  This increased energy (I think that is due in large part to Peter Gunn's crossover mod) is probably why people report it has "more of everything Maggie" and "increases efficiency by 6 dB" comments over stock MMGs.  That increased midrange messes up linearity (again, in my shed; sounded great at Steve's place) but the Behringer takes care of that easily.

The best parts of the Magnestand MMG mod are:  1) increase in clarity, most likely frpm the substitution of the original MDF to hardwood, resulting in a palpable sense of what I call "immediacy" (the sense that a drummer, pianist,  guitarist is right there in the room with you); 2) a slight extension of bass, so the bass dropoff frequency went from 50 Hz stock to 45 Hz (again, in my shed); 3) the crossover results in an almost perfect merging of the tweeter output over the entire width of the planar mid/bass driver, making extreme nearfield listening a pleasure, since you don't hear the tweeter as a separate driver; and 4) PG does exceptional woodworking, making each mod a totally unique work of art.  I will say that my system could not portray such a sense of realism without the Gunn mod.

I could give a short course on how to use the Behringer effectively to increase resolution and realism.  I will say, though, that it is a 3 part process: 1) use the software built in the Behringer along with a measurement microphone at the listening position to equalize pink noise through the speakers so the response is as linear as possible, 2) manually tweak the result so that all the settings are subtractive; and 3) apply a "secret sauce" EQ curve over the EQ settings of step 2) to make up for the fact that almost no real world recordings are mastered to sound good on a truly flat transducer. 

Also worth mentioning is my use of twin braided 26 AWG solid magnet wire as 6 foot long speaker "cables" (I call them threads) and "chokes" (Miller Fixed Inductors 10uH 10% model 5522-RC) wired in series with the tweeter leads to help combat RF.

http://www.mouser.com/Search/ProductDetail.aspx?R=5522-RCvirtualkey54200000virtualkey542-5522-RC

I'll post a bit later with details about the room placement and latest FRT setup.  'Till then, ciao!

MGbert

[JohnR]

I really have to eat my hat on this one as even very recently I was slamming digital EQ and suggesting just here on AC that people avoid these devices.  That is, that these devices did "violence" to the original signal, particularly if or when they were used between a preamp and amp and doing analog to digital then back to analog conversion.  Of this latter point I'm still clinging to until I experience evidence to the contrary

So... when you were "slamming digital EQ" was that based on any actual experience with the technology?

[THROWBACK]

Although I do not have Maggies anymore (used to have 20's and 20.1's)--nor am I a KR (who?) fan--I really enjoyed the discussion on this thread. The writing--particularly by jarcher and MGbert--was informative and entertaining and captured the love we all have for our hobby. It's why I keep turning to the Audio Circle every day.
Thanks!

[jarcher]

So... when you were "slamming digital EQ" was that based on any actual experience with the technology?

In part, yes, and in part, on principle.  Experience : Not too long back I heard a mega-system where the guy had gone to incredible lengths : everything from enormous 6+ tall speakers, hugh high end mononblocks (and suitable preamp), dedicated outlets + lines for EACH amp, a highly rated Oppo 105 as source, a dedicated room w/ extensive acoustic treatment, etc, etc.  Because he had chosen the speakers without crossovers, he had chosen to use an external digital crossover between the preamp & amp.  It was a modest pro audio digital model and did analog to digital then back to analog conversion of the incoming signal.  Here I was thinking : this guy has assembled all the finest components, dedicated and treated his ENTIRE living room to it, and in the end does violence to the entire endeavor by passing it through the A/D - D/A section of a cheap pro audio crossover?  Through the listening sessions I had felt there was a residual "hardness" to the sound, and now I understood why. 

In principle I've always favored a keep it simple / pure path approach to audio gear using the best parts / components.  I.e. the kind of thinking you see with say AVA or Conrad Johnson gear.  With the exception of home theater where you have so much "information" and channels to contend with, I've always tried to avoid digital signal processing (eq or otherwise) as an unnecessary manipulation of the signal that does more harm than good.  Marc's accomplishments have made me reconsider that, at least in the digital domain prior to the final analog conversion stage.  I think thats a reflection of how good the gear has become (digital eq) as well as what can be accomplished with it by someone who has the ability and patience to use it correctly. 

I'm still not convinced I would want to mess with analog signals if it required an analog to  digital then back to analog conversion - e.g. in dealing w/ say a turntable cartridge signal, or worse yet at the final analog pre amplification to amplification stage.  Though there are certainly plenty of people that have carefully digitized their LP collection & report no discernible sound quality difference.  I'm certainly more open to being less dogmatic about that if I were to hear an example where more good than harm was done. That's why I'd be curious when Marc get's his TT up & running what his experience will be there.   I guess the real lesson is to keep both your ears and mind open!

[Davey]

The real item of interest here hasn't been mentioned yet.  What does the overall "correction" curve programmed into the DEQ2496 actually look like. 

Cheers,

Dave.

[NIGHTFALL1970]

What, no track listings?  What you remember hearing that "grabbed" you?

[MGbert]

@ THROWBACK: Thank you for the kind words!  When I re-read my posts, it always seems they're a bit pedantic... and long!  So thanks for your patience.   

@ Davey:  The Behringer is good at many things, but downloading it's data to a computer isn't one of them!  My son has hidden our camera, so when we find it I'll snap screenshots of the Behringer's EQ settings screens and RTA results.  Soon, hopefully.

@SteveFord:  Kinda knew you'd want pix.     See above.

@ NIGHTFALL1970:  I'll let jarcher and pansixt speak for themselves.  I will say, though, that except for a few "audiophile" cuts, like "Miles Away" by Sara K and the Dave Brubeck Quartet's amazing Carnegie Hall Concert, my choices usually had aspects which stood out of otherwise average sonics.  "Pioneers Over C" by Van der Graff Generator and "Shindig" by Mostly Autumn, for instance had sounds licated well in front of the plane of the speakers, and in the case of Shindig there is a rhythmic synthesized bass riff actually located at your FEET.     It's finding these easter eggs amongst recordings I've heard many times before that keeps this fun.

MGbert

[jarcher]

What, no track listings?  What you remember hearing that "grabbed" you?

What Marc said : Miles Away" by Sara K on a Chesky Jazz & More Vol 2 album, and the Dave Brubeck Quartet's amazing Carnegie Hall Concert album : and I'm actually tired of hearing the "Take 5" album overplayed , so this was a refreshing change. 

Sorry : no KR/KJ (Keith Jarrett) !  had to get that in there. 

Marc humored me w/ some prog rock stuff that had on occasions a bit of a heavy metal bite courtesy of an Izz concert video.  System can rock out!

[Davey]

@ Davey:  The Behringer is good at many things, but downloading it's data to a computer isn't one of them!  My son has hidden our camera, so when we find it I'll snap screenshots of the Behringer's EQ settings screens and RTA results.  Soon, hopefully.

Yep, I understand.  Screen 1 with the PEQ button pushed should show your overall EQ settings.  (I'm assuming you used the PEQ capability and not the GEQ.)

Also, one of the users on DIYaudio a number of years ago wrote a handy Windows utility that will allow communication via the MIDI connections on your unit.  One of the features is allowing to capture the current screen on the DEQ front panel and save to the clipboard.

http://www.diyaudio.com/forums/digital-line-level/53088-deq-2496-remote-controll-under-construction-myself.html

Cheers,

Dave.

[ricardojoa]

Im still a bit confused about the AD conversion. Why not just sent a digital signal to the dsp and let it do the conversion to analogue. Skip one step.