[Saurav]

Ideally individual driver measurements, but complete speaker measurements would be interesting too. I've seen the measurements from the Enjoy The Music review, those are the only ones I've found so far. I've had an idea for some time now, take my 12" dipole woofers, put them in a small H-enclosure 'box', put the MMG's on top. Before I embark on such a project, I'd like to have some idea of what I'm getting into.

[SteveFord]

http://www.htguide.com/forum/showthread.php4?t=22186

[Saurav]

Thanks. I've seen that thread. Unless I missed it, the only measurements posted are of the MMG-W.

[SteveFord]

Crap, you're right.
Could someone with MMGs do a measurement, please?
If I had some they vanished when my hard drive was attacked by a virus.

[Davey]

What measurements would you like to see?
I can make them look like whatever you want. 

Cheers,

Dave.

[Saurav]

Everything you have?

If you use ARTA or HolmImpulse, it would be awesome if you could share the raw impulse files for each driver as well as the combined speaker, along with some information on the measurement conditions - indoors vs. outdoors, room size, mic distance, what crossover is in use for the full speaker, etc. Then I can use the software to look at the gated response, ungated / smoothed response, etc., and have some idea of what I'm looking at based on the measurement conditions.

If you can't share the raw data, or you use some other software, then the charts I'm most curious about are the gated measurements for the individual drivers (just the drivers, no XO in place), and the gated as well as ungated+smoothed measurements for the full speaker.

Thanks!

[Letitroll98]

All the in room measurements are going to vary so much that you really won't be able to do any real work until you measure them in your room.  However they are just about perfect for adding a sub, rolling off steeply below 55 hz in my room, then a little room gain shelf at 40 hz, fairly easy to integrate a sub.

PS. Davey, how much per hour are you charging for generated lab data these days.     I think maybe Saurav should buy a pair and generate the data he needs rather than commissioning you for it, might be cheaper in the end.

[Rclark]

I still absolutely love my modded mmg's even after demoing a speaker recently and hearing a sota tweeter. Can't wait to get some bigger, better amps on them and hearing what they can fully do, but as of now they are pretty much heaven. I couldn't ask for much more that a few subs couldn't provide.

 I would also love to see measurements of stock, then I will figure out how to measure mine.

[Saurav]

All the in room measurements are going to vary so much that you really won't be able to do any real work until you measure them in your room.

Agreed completely. If/when I try this out, I'll definitely be taking my own measurements. Right now, I'm just trying to get a feel for what to expect. This may be a project for later this summer.

PS. Davey, how much per hour are you charging for generated lab data these days.

I didn't think about that, I was assuming that Davey had all the data sitting on a computer somewhere. If you need to take new measurements, then please don't bother, that's not what I was asking for at all.

[Davey]

I need to put together a proper MMG page that consolidates my information in a nice format.....unlike the mess I have now.    I'll get on that.

It's challenging to measure/interpret data from a large speaker like the MMG's.  That's what I meant with the "make them look like whatever you want" comment. 

You really need to take these measurements with the speaker outdoors so you can exclude room interactions and put the microphone at a decent distance so the response can "coalesce."  However, even that doesn't yield a meaningful baseline of measurements (to design with) because the listening room interaction and the dipole characteristic is a key aspect of how these sound in use.

I would suggest you take your own measurements.....I wouldn't trust anybody else.

Cheers,

Dave.
 

[Saurav]

You really need to take these measurements with the speaker outdoors so you can exclude room interactions and put the microphone at a decent distance so the response can "coalesce."  However, even that doesn't yield a meaningful baseline of measurements (to design with) because the listening room interaction and the dipole characteristic is a key aspect of how these sound in use.

I've measured my current speakers out on the deck, as well as in the room. Like you said, you need to look at all of it together.

I would suggest you take your own measurements.....I wouldn't trust anybody else.

If I go ahead with this project, I'll definitely be taking my own measurements and designing my own crossover. Like I said, right now I'm just trying to get an idea of what I would be dealing with. If you don't feel comfortable sharing your data because I or someone else might misinterpret it, I understand.

[dawnrazor]

Crap, you're right.
Could someone with MMGs do a measurement, please?
If I had some they vanished when my hard drive was attacked by a virus.

hey Steve here are the ones you sent me from Wendell.

They were pdf but I made them into picts.  The were a bit mislabeled and still are here.

[Saurav]

Well, I wasn't planning on this, but I was idly browsing Audiogon this weekend, and found a pair of MMGs for sale locally. Didn't spend too much time thinking about it, and now I'm the proud new owner Got them set up last night, currently trying a 60Hz-ish XO to the sub. I haven't pulled out any measuring gear yet, so it's just tweaked by ear for now. I'll leave it like this for some time while I get used to the sound before I try to make any changes.

[Letitroll98]

Congrats on the purchase.  You may find you end up with a touch lower crossover point at the end of the day, depending on your setup and preferences of course.  Mine gets set at 50hz.

And funny with Wendell's FR curves, it's almost exactly what I came up with and I spent forever trying to correct the room's "problems".  Wish I would have known it was in the speaker.

[SteveFord]

Letitroll98,
Have you tried a DMW or two with the MMGs to smooth out the response curve?
Oh yes, congratulations, Saurav!

[Rclark]

congrats! I sure love mine!

[Davey]

Congrats on the purchase.  You may find you end up with a touch lower crossover point at the end of the day, depending on your setup and preferences of course.  Mine gets set at 50hz.

And funny with Wendell's FR curves, it's almost exactly what I came up with and I spent forever trying to correct the room's "problems".  Wish I would have known it was in the speaker.

50hz is way too low a crossover frequency for MMG's......IMHO.  They're running out of gas well above that.

More than likely it was a room "problem."  It's very difficult to get meaningful measurements (in room) with a system like the MMG's...at lower frequencies.  Even MLS-based systems can yield confusing results because any kind of meaningful measurements require a long enough time window that the results are no longer anechoic.

I wouldn't read too much into those measurements supplied by Wendell.  The fellas at Magnepan have just as much difficulty with these types of measurements as anyone else. 

A completely free-field (outdoors with no boundaries) measurement of the MMG yields a pretty darn smooth response.  As you move down in frequency you see the expected roll-off (these are not full range speakers) but it's still fairly smooth.  This is the only way to get a really good look at the speaker response...by itself.

Any of the new-fangled "room correction" systems are a complete misnomer and a questionable concept to begin with.

If you try integrating a woofer system with the MMG's you may or may not get a smoother response......depending upon woofer type, room placement, crossover frequency and type, electrical time delay added, etc, etc.

Cheers,

Dave.

[Saurav]

50hz is way too low a crossover frequency for MMG's......IMHO.  They're running out of gas well above that.

Funny you should say that. I started with 80Hz, then tried 40, then moved up to 60. I think I'll try 80 again. That almost sounded like there was no upper bass hole. Of course, I was tweaking by ear, not even the RS SPL meter, and I've done this enough times to know that I always get smoother integration with the mic and REW. My sub is fairly well equalized, so it's a matter of finding the point where the MMGs start to drop off in my room.

If you try integrating a woofer system with the MMG's you may or may not get a smoother response......depending upon woofer type, room placement, crossover frequency and type, electrical time delay added, etc, etc.

This was my original plan, but now I'm wondering if a higher sub XO might just be good enough. If I go down this route, it will be with the DCX2496 driving the whole thing, and a full XO between the MMG and the woofer. Frequency/slope/etc. would depend on the measurements of course.

[Letitroll98]

I agree the speaker is rolling off before that, but niether is the sub rolling out at a brickwall 50hz either.

I also agree about the measurements in the bass. I was looking at mids and treble, I didn't specify that, sorry.

50hz is way too low a crossover frequency for MMG's......IMHO.  They're running out of gas well above that.

More than likely it was a room "problem."  It's very difficult to get meaningful measurements (in room) with a system like the MMG's...at lower frequencies. 

Cheers,

Dave.

[JohnR]

Saurav, will you be measuring the MMGs (/+ dipole woofers)? I understand what Davey is saying but even in-room measurements are better than nothing. As I recall you have a pair of the same drivers I have.