In wall planar setup with 15's and active processing...?

[captainobvious]

My wife and I are moving into a larger home with a huge great room. The room measures appx 18' front to back and 40' left to right. The ceiling height is appx 15' +. It was formerly a garage turned into a great room with the ceiling taken up to the roof. I'm envisioning a large home theater/stereo setup which would use a build out off the wall over a large section to house the drivers and their airspace and provide plenty of baffle space all while keeping a more integrated look (no speakers sitting on the floor anywhere).
Because of the size of the room and my intrigue by them, I wanted to give the Bohlender Graebener RD75 a shot. They could be built into the wall in sealed cabinets and with plenty of baffle space to provide better low end response and then be mated up to a large woofer to carry the rest of the low end spectrum. Through reading, most users have recommended a 300-400hz crossover point for the RD75 when used sealed (instead of dipole) to limit the low frequency extension and distortion. I'd like to implement a 2-way using active processing (DCX2496 and DEQ2496) so I'm looking at options for the low frequency driver. The RSS390HF seems like it may be a decent candidate with its low Le and low overall distortion design, decent sensitivity and low Fs with good xmax. It looks like the response is good with breakup past 1K so a crossover point 2 octaves below that with 2nd or higher order slope sounds like a good workable option. In a room that size, would one RSS390HF for each side be enough to play with serious authority for music and movies or would I need to consider 2 per side? I'm also assuming I would want to keep them low to the floor to couple for increased output?
With all of the space available and the mounting dimensions, I could have a 12" build out off the wall that is as large as needed to house the enclosure volume and have the projector screen cover a large portion of it as well with grill covers for nicer aesthetics.

Thoughts on the RSS390HF or any other options that might be better suited?


Thanks

[Notloudenuf]

15 x 40? Build a stage, book acts, sell tickets. Better than speakers

[captainobvious]

Hah!

Yeah it's quite a large room. Would be pretty sick to have (4) 15's and a pair of 75" planars in a killer two-way all in a built in and hidden behind grills. Very high WAF and still amazing performance. There's a cutout area in the back wall that could house a rack for all of the amplification and processing, media and gaming systems, etc.

[erinh]

although your room is nearly twice the size of mine, it sounds like you're going the same route I am. I'm assembling gear and will start my baffle wall build next month. I'm shooting for the 'movie theater' vibe, and the benefits of a full wall are really great acoustically and cosmetically.

I will say... only 4 15's? Dude, that's a big room. You need a few of Nick's 24's.

In all seriousness, have you considered placement of the low frequency speakers? And you may truly need more output in a room that size, depending on your listening habits and goals. What's the efficiency of the planars? How many of (whatever woofer) do you need to match that?

[ca90ss]

Have you looked at Magnepan? They have some wall mount speakers. Not exactly flush mount but still very thin.
http://www.magnepan.com/model_MMGW

[captainobvious]

although your room is nearly twice the size of mine, it sounds like you're going the same route I am. I'm assembling gear and will start my baffle wall build next month. I'm shooting for the 'movie theater' vibe, and the benefits of a full wall are really great acoustically and cosmetically.

I will say... only 4 15's? Dude, that's a big room. You need a few of Nick's 24's.

In all seriousness, have you considered placement of the low frequency speakers? And you may truly need more output in a room that size, depending on your listening habits and goals. What's the efficiency of the planars? How many of (whatever woofer) do you need to match that?

BG RD75: http://www.parts-express.com/bohlend...ducer--264-700

The planar's are a 75" line source driver with frequency response very usable from 350hz on up. They have 88db sensitivity and power handling is listed at 100wRMS/200w program/400w peak so they can certainly get very loud.

I was going to place the low frequency speakers on the front wall close to the floor to try to couple for some semblance of gain. They cant really go in corners so they may as well be up front where they can be hidden in the wall. As for Nicks 24" - hahaha yeah I'd have to sell the house to afford the subs for the house. I do like the low cost of the HT18's but they don't seem suited for use as high in frequency as I'd want them to play. In the end, I may end up having to do dedicated subs, but we'll see. The Dayton RSS390HF is a very low distortion subwoofer and can play a little higher while still offering good low frequency response. They don't have a ton of xmax though and I probably wouldn't want them to be working that hard anyway so I'm still thinking of other options. I could probably do a pair of the 12" RSS315HF or RSS265HF 10" for each side and then 2-3 of Nicks HT18 for the bottom end http://stereointegrity.com/product/ht18-18-subwoofer/


Yeah the wall will provide a large baffle and nicer aesthetics for WAF. Would be great to have everything hidden pretty stealth like yet have insane sound.

[captainobvious]

Have you looked at Magnepan? They have some wall mount speakers. Not exactly flush mount but still very thin.
http://www.magnepan.com/model_MMGW

Yep, I actually owned a pair of Maggie's years back. I prefer the electrostat's over them, but even this is possibly a better solution and takes up less space in the room overall too which is a nice bonus.

[Notloudenuf]

pics of the new house?