[MRoerup]

Hi Davey.

I know this is a rather old thread but if you are still listening....

I have seen that you have answered several other users request for information on your Magnepan sandwich construction approach, by referering to this URL: http://home.comcast.net/~dreite/MMGframe.htm

Unfortunately the link is now stone dead and have been so for a while. If you still have your pictures and text for that project, I would kindly ask if your would republish them. I'm sure there are a few other guys around who also plans to mod our Mag-frames and would love to see your design.

Many thanks for considering my request.

Regards
Martin Roerup, Denmark.

[Davey]

Martin,

Thanks for the interest.  I will post the photographs in an alternative location and/or figure out a way to re-establish the old location.  I took that previous page down for other reasons.  It's a long story that I related to Steve Ford awhile back. 

As it happens, I'm between other speaker projects right now and those MMG speakers are playing at this very moment. 

Dave.

[SteveFord]

Post them here if you'd like, I'm sure the members would be interested.
We do like our Planar Porn here!
I still think that was a stroke of genius when you suspended the MMGs from the ceiling.

[Davey]

There was no genius involved.  It was a practical solution, that turned out to be excellent from a performance aspect.
'Not workable in most folks listening rooms because of normal ceilings and poor WAF. 

Dave.

[Davey]

Regards the MMG frames:  This is probably the best single photograph.  A couple of temporary clamps holding the two halves together and you can clearly see the gap created by the sandwich construction.  Note the little notches to accommodate the transducer cross-braces.

Dave.

[MRoerup]

Hi Dave.

Thank you very much 
I remember seeing that picture some years ago. This is exactly what I am looking for. If you will post more pictures I would appreciate it very much, although the one picture probably tells the most essential stuff...
I definitely want to build such frames in a hopefully not too distant future. I just have to finish some other project first about building some absorber and diffusor panels.

There is however one question I would like to ask.
I have read a lot about the curvature of the Magnepan Polepiece units but I'm afraid I haven't fully grasped the concept here. Purhaps because English is not my native language!!!
If the Polepiece is slightly curved, I guess along the top and bottom sides, what happens when we place the panel inside a sandwich frame which seems to suspent the panel equally on all 4 sides? Will we not then strech out the Polepiece curvature here?
I hope the question made some sense 

Regards
Martin Roerup

[Davey]

The curvature of the panels is minimal, and framing them in this way does not alter it.  The clamping pressure should be light (and only on the edges) so it doesn't really exert any straightening force.

The thickness of the spacer between the two panels is fairly important since you want decent contact between the panels and the transducer unit.....but you don't want a death-grip on it either.  I did some smoothing with sandpaper on both sides of the transducer units to give them a smooth surface.  The black paint can be somewhat thick and runny in places, so it's good to smooth it down.

These speakers were completed in 2009 and have been in semi-regular use since then with no issues regards performance or longevity.

Dave.

[ehoove]

About seven years ago, I constructed and put my MGIIIa's in solid maple frames. They have been actively Tri-amped for 5 years using a Behringer DCX2496 with modifications. I also run a pair of NHT W2 subs with the NHT X1 crossover. This setup stopped my upgrade thoughts in their tracks, and the mods allow me to listen to any genre music. The maple frames really increased the dynamics of the speaker, and reduced any overload in the speakers at high volume. They have never slapped since in the maple frames.
Regards,
Jim