Expert opinions sought on choosing HT speaker set

[mrel]

Firstly thanks to all the contributors to this forum. It's an amazing resource.

I've been reading for about 6 months and trying to finalise which designs to build for a DIY set of 7.1 HT speakers.

The room
We're actually building a new house so I will be designing the theater from scratch. My plan is a false front wall with an IB subwoofer system in it.
I want to put an LCD/plasma (for daytime) on this wall with a motorised screen dropping down in front (for nighttime). I'm hoping for all the trimmings - starfield ceiling, soffit rope lighting, acoustic treatments, etc.

LCR
The false front wall means I have heaps of space at the front. I want the LCRs to mount flush with this wall. I envisage 'proper' cabinets, just mounted flush. I like the Khanspires or RS 3-ways but need a version with a no-BSC crosssover due to the placement. I can use a router and saw but crossover design is all greek to me!
I will have to use a horizontal centre to go under the LCD/plasma.

Surrounds
For the surrounds, I want them to be mounted on-wall, possibly in columns. I don't want to go in-wall because I think this would reduce the noise attenuation of the room.
On-wall placement then means I need a 'shallow' cabinet. A tall front baffle is no problem but I don't want them to stick out into the room. Maybe mounted slightly higher to give a more diffuse field. Really want to try to de-localise the speakers, esp the sides.

Choices
Here's a summary of what I think my shortlist is, with my pros/cons:

Khanspires/center/neatos
There are no-BSC crossover designs available. However I'm concerned about the min depth of neatos - I think 6.5" is the min recommended depth? However, the TMW design of the neatos would be better for mounting higher on the wall than a MTM design.
Virtually unlimited space in the front wall - I can go physically bigger than the Khanspires...

RS 3 ways / WMTW center / Nat Ps
I can't find a no-BSC crossover for the big 3 ways. Can anyone point me in the right direction?
I like the idea of the RS225s in the 3 ways - I have enough space so bigger woofers are always better, right? I am led to believe that IB subs still require good bass performance from the mains?
Nat Ps I think can be built 'shallower' than Neatos, but the MTM design might not be as good mounted up high on the wall. I could use the Modula MTs instead - will these keep up with the rest of the system? (given that these days theaters are meant to have fullrange surrounds) How do NatPs compare to the MTs in performance?

Others
Am I missing other options? The cost doesn't worry me too much, I'd rather do it right first time than always wonder if I should have spent more.
There's so much awesome info here, it's just hard to sift through for exactly what suits my needs!

I think if I could get a suitable crossover, the 3-ways, RS WTMW center and Modula MTs might be the best solution?

Thanks to anyone in advance for any suggestions, guidance or advice.

[Jed]

The Dynamic Series would work in your room as well. Baffle Step is easily adjustable with a couple resistors- if you wanted to say mount a 1S or 4CC on the wall or under a flat screen TV. I've got a few people building 7.1 systems with these speakers with a similar scenario as you.

[cjd]

The in-khans can mount partially out of the wall.

I have a full in-wall HT setup in mine, i'll be buffing up the designs and sharing those finally in the next couple weeks. Slight downsize from the Khans.

With the effort you're putting into this, can I suggest instead a LCD that rises from a cabinet below the screen? Just go phantom center when you use it and have 3 real vertically oriented speakers behind your main (fixed) screen.

[mrel]

Jed,
Thanks very much for the reply. I hadn't seen your website before -your designs look awesome.

A couple of quick questions - your 4Ts and 4CC look like (from the build pictures) they are rear-ported - or am I seeing something else? Obviously in my application I'd need a sealed or front-ported design - is this possible?

Regarding 1S as surrounds - these are ported too, aren't they? I suspect this will mandate how 'shallow' their cabinet is? I'm ideally looking for a design that sits a bit more flush with the wall.

Maybe we should talk in more depth?

[mrel]

CJD,
Thanks for your reply. That's a good idea about the LCD on a lifter.

In fact maybe I'll do away with it completely. I always thought it was a good idea to save projector bulb costs but you can buy a few bulbs for the cost of the LCD...

Looking forward to seeing your in-wall HT designs. What sub are you using with them?

[Jed]

Maybe we should talk in more depth?

PM on the way.

[---k---]

If you're going to be going all out on a new home theater, you should check out Floyd Toole's new book, Sound Reproduction.

http://www.amazon.com/Sound-Reproduction-Acoustics-Psychoacoustics-Loudspeakers/dp/0240520092/ref=sr_1_1?ie=UTF8&qid=1248441430&sr=8-1

It has quite a bit of insight on constructing a home theater, and a LOT of it is quite different than the usual recommendations found in the industry and internet. I'm not sure yet if I agree with him, but he is probably the leading expert in the field, so who am I to argue?

[cjd]

Looking forward to seeing your in-wall HT designs. What sub are you using with them?

A handful of people have been hankering for my HT speaker design.

Sub? Hah! you ask what sub...

an "IB" sub consisting of 4 15" Tempest-X drivers manifold mounted.

[CAAD]

I use my projector for all of my daily viewing. My fish tank ends up being far more expensive anyway, so I figure it's a relatively small percentage of the hobby operating cost budget.

Are you planning to have an AT screen? Whatever speakers you choose will offer an even better experience if they're behind the screen. Once you experience one, you may have a hard time going back.

[cjd]

The way lightbulbs wear over time you're better off using it up faster anyhow.

[mrel]

Hey thanks guys for all those that have replied.

It won't be my first projector so I know how good it is and how worthwhile that big screen is. Am now leaning towards an AT screen. As CAAD says speakers behind the screen must be the way to go. And I feel the pain - I got rid of my 5 expensive (discus) fish tanks...

[mrel]

CJD,
How low do your mains need to go, to integrate with the IB sub? I read somewhere that your LCR set needs to get down around 40Hz comfortably to integrate well. Your comments?

I'm planning for 4 x IXL 18s in mine. They're nearly the same price here in Aust as the 15s so mad not to get the 18s, right?

[Paul W]

I second the book recommendation Ryan made...the best investment you can make in an AV room.

With a false wall and 4 IB subs, consider a "Planar Bass Array" with the 4 subs placed at the 25% & 75% width and height points on the front wall. The PBA will go a long way toward minimizing the height and width modes in the room, leaving only the length mode to deal with. With subs firing straight into the room, the front wall must be very solidly braced to something behind it to prevent vibration. I also suggest using something like a Behringer FBD to notch subwoofer cone breakup and provide any remaining EQ.

Consider angling the outer sections of your front wall toward the listening area to reduce reflections off the near side walls and put the listening area more on-axis with the L&R speakers.

I agree 40 Hz is a good target for your mains. I'd go with one of the larger 3-ways with identical vertically oriented LCRs behind an AT screen. The new Seymour XD screen material is the best I've found so far.

[cjd]

I cross at 60 or 70Hz, I don't recall. The sub is mounted just about below the center channel (it's slightly off center) and I don't note any issues with sound integration - it works well even at 80Hz. The RS180 can run into excursion issues being asked to play back soundtracks crossed much lower.

Absolutely go with an AT screen - if you want to go the DIY route check out Seymour AV (wonderfully affordable too) - or get a premade screen from SMX. Base materials are about the same (I think SMX has done more development, research, something...) Mine is very true on color after calibration and the sound roll-off is very even and surprisingly mild.

[CAAD]

+1 on SMX

[mrel]

Thanks to everyone for advice on screens etc.

Back to the original problem though - can anyone point me toward a "no-BSC" crossover design for the RS 3-ways?

Or particularly 'shallow' surround designs? Like wider and flatter rather than skinny and deep?

[Hdale85]

Don't think there was a no BSC version.

[Brian Walter]

Thanks to everyone for advice on screens etc.

Back to the original problem though - can anyone point me toward a "no-BSC" crossover design for the RS 3-ways?

Or particularly 'shallow' surround designs? Like wider and flatter rather than skinny and deep?

Assuming you are talking about the WWMT 3 ways, they were designed by Dennis Murphy, you might want to send him an email to see if he would work up an non-BSC design for you. I know he goes by the name framus over on the PE forum, you could send him a PM from there. I'm not sure if he is a member here or not.

Brian Walter

[---k---]

I thought he was talking about CJD's big RS 3-ways, since CJD was pimping them earlier. Which is exactly why I'm in favor of a new rule, "All speaker projects must have a cool, unique name!"

[cjd]

There will not ever be a "no bsc" version of the big WWMTM's. If you can mount them on the wall you still need BSC - and in this case in-wall would need more dramatic changes to balance SPL. If you've got room for 20" deep speakers in a wall, just make the damn wall acoustically transparent, move them out ~6-8 inches more and use the full BSC versions.

[mrel]

Ummm, sheesh, sorry CJD!

The wall I wanted to put them in forms the baffle for an IB sub, so acoutically transparent won't work.

OK, at least now I know. Strike out that speaker design as an option....!

[cjd]

Ummm, sheesh, sorry CJD!

The wall I wanted to put them in forms the baffle for an IB sub, so acoutically transparent won't work.

OK, at least now I know. Strike out that speaker design as an option....!

Nothing to be sorry about. It would just take a notably different approach - probably would just have to switch to using the RS270's in series, but I don't have data for this in-wall and it's not something that I would want to try to extrapolate - the cost is too high on the parts for me to be comfortable doing that.

Do an outie IB sub manifold and you'd have space for these again.

But yes - if you need flush-mount the WWMTM's won't work for you. And there's nothing wrong with that at all.