Electromotion R backbox query plus new install advice needed

Greetings from the UK .. first post here and a very happy summit x owner.

I've bought 4 Electromotion R's for an Atmos install and will be inserting these in a floating ceiling design.
I will be adding substantial sound proofing to my room 6.2m by 3.9m and 2.6m high using resilient bars and double boarding. A big concern is the sound leakage into ceiling and subsequent bedrooms upstairs.
I've seen but not heard the dynamat rubber bag type solution , but was wondering if a mdf back box would do a better job?.
The joists are abround 100mm deep, 400cm wide although I'm looking at an additional layer of ceiling to partially conceal a projector.
What volume do the Electromotion R ceiling speakers require if put in a back box ?

Second query is what ML speakers should I use for the surround side and backs. Probably will go for the Electromotion IW, but looking at the spec's the bass response is not that great, as the cone size is not as substantial as the EM-R's.

Has anyone had experience with the IW's, are they bass shy ?

The price of the Stealth Axis model, at the moment is on the high side for the remainder of the budget. I wasn't expecting the projector screen to cost me so much.

Although the EM-R is specifically designed for the ceiling , has anyone installed them in-wall?
The angle of the driver could be positioned so the ribbon tweeter is at a sufficient enough angle to direct the sound better to the listening position. I will experiment , unless there are other reasons why this is a bad idea.

Thanks in advance .

we have been worked with the Dynamat solutions and one the greatest strengths they have is in back wave attenuation. A solid material like mdf of a backbox doesn't have much more than 10 db of attenuation whereas Dynamat can reach 46 db. No comparison.
As to using EMR in a wall, as long at the orientation fits your needs, it can be done just fine.

Peter Soderberg said:

we have been worked with the Dynamat solutions and one the greatest strengths they have is in back wave attenuation. A solid material like mdf of a backbox doesn't have much more than 10 db of attenuation whereas Dynamat can reach 46 db. No comparison.
As to using EMR in a wall, as long at the orientation fits your needs, it can be done just fine.

Click to expand...

Wow that good ..thanks for info . Nice to hear from someone who's used them in anger.

I shall wire up the EM R's and have a play

Looking at the DynaBox measurements 43cm x 31cm x 16cm the 31 and 16 are a very snug fit .. Are the EM R too big for the enclosure?

As for side and rear wall orientation at about 7ft the drivers angle downwards towards the listening position ..and as I can get these at a keener price this might be a solution

Well I decided to go for 4 EM IW for the surrounds.

As for sound proofing I,m having to cut back on the grand scale of things for the room build.
The Dynamat solution will be more costly as these would have to be imported.
Anyone know the volume required if I was to build a back box , for both the EM IW and the in ceiling EM R's?

Many thanks.

send me an email directly at [email protected] and I can send you an internal volume calculator so you can build them.

Peter Soderberg said:

send me an email directly at [email protected] and I can send you an internal volume calculator so you can build them.

Click to expand...

Thanks very much