Amplification and Speakers In Huge Home Theater


I am re-tooling my home theater to get more speaker coverage in my very large room. I do not want to use a subwoofer(s) because of the expense. If I ran subs I would want to run four of them, and I just don’t have the kind of dough for four high-quality subs. Besides I live in a loft with neighbors on both sides…multiple subs would be just too much.

I had been using Infinity Kappa 9 speakers as fronts, center and surrounds. I had been running them with Carver Silver 9t monoblocs. The Kappas are notoriously inefficient power hogs. They are beautiful great sounding speakers, they just need a LOT of power and I’m looking to move on to something more efficient. Also, the Carver monobloc amps are getting up there in age (20 years?), and they may fail soon and I’d like to replace them all with one multi-channel switching amp (Wyred4Sound) and one stereo amp.

I am considering getting four pairs of indentical Cerwin Vega speakers for a 7.1 system. Each of these speaker towers will have two 18 inch woofers per speaker, for a total of eighteen 18 inch woofers in the system. The speakers are rated to go down to 24hz. I will also use one of these speakers as the center channel. Every speaker in the system will be set to “Large”. With that many 18 inch woofers going that low, there will be no need for a sub.

Two (48" tall) front tower speakers will sit on the floor, one on each side of the screen….sixteen feet apart. Another pair of front speakers will sit on the floor along the front side walls about eight feet out into the room, 22 feet apart. I am using an extra pair of front speakers to help fill the room with sound. The four front speakers will be Y-connected to facilitate the two speakers per side.

The surround speakers will be ten feet high off the floor, 22 feet apart, twenty five feet away from the screen.

The back surround speakers will be 35 feet away from the screen, fifteen feet apart and elevated five feet off the floor.

My sitting position is twenty five feet from the screen. Any closer and I get pixelization.

My room is 22 feet wide, 70 feet long and 22 feet high.

My screen is 16 feet wide and 12 feet tall.

Photo of room with screen rolled up

Photo of room with screen rolled down

Photo and specs of Cerwin Vega speakers I want to use

Photo and specs of the Wyred4Sound multi-channel amp I will use

This room is also my living room. So before you start to think of all these big ugly speakers killing the room aesthetics, all of the speakers will be ingeniously hidden and stored away when not in use. This system will be used for home theater only, my two channel system will remain separate.

I will be using a Marantz AV 7005 as my processor.

I would like your feedback and opinions on this system regarding the bass output capability while not using a subwoofer.
128x128mitch4t
What's your budget here? If you're willing to spend, Definitive Technology will blow away the Cerwin Vega as far as movies go. Top dog is the Def Tech BP 7000SC if you can get your hands on one, they're hard to find with 18-inch built-in subs will shake your ground here. For center, go with the C/L/R 3000 and maybe a pair of BP7002 for rear. I guess is around $3500 used if you can find them. Trust me, your Home Theater will never be the same.
The Cerwin Vegas have two 15" woofers yet the -3db point is only 38hz. There are a lot of speakers with smaller drivers that play lower than that. With the Cerwins you will need a sub for home theater.
Yeah Prpixel, down 3db at 38hz and down 10db at 36Hz!!!!

I don't think I have ever seen such a precipitous drop-off at the bottom end. If the link is the actual OP speakers (he is planning on buying), then he will definately need a sub.

My recommendation is to go with much higher quality speakers. I suspect this many CV's in a room are going to drive somebody crazy.

My recommendation is to contact a local movie theatre and ask for a tour or the name of who they worked with on installing their movie sound systems. I think the current plan is fraught with all sorts of problems.
.
Thanks guys, I was looking for a way to do this for a lot less money than it is actually going to take.

I'll go back to the drawing board and save up some more dough and try this again another way.
.
Mitch, I would re-consider the subwoofer aspect. I think you would be better of with speakers that are going to give you a tighter bass than the 15/18" dual drivers on the CVs. My guess is there will be a lot of bloat or flabbiness with those speakers.

Maybe if you drop down in their line to speakers with 8-10" drivers and use the savings to go with 2 used subs, you may find your goals more feasible.

Of course, none of us that followed your link could find the speakers you referenced with the 18" drivers and extending down to the 24 hz. range. Maybe you can post an updated link to the correct speakers?
CHeck out the speakers from JTR. Once called the triple 12HT and their Growler subwoofer. Their has been a fairly extensive thread about this line of speakers and subs over at AVS forum.
Dude,

I absolutely love the way you are thinking...extreme HT. :-D Love it! I have heard the CWs you are looking at, and agree with the previous posters that you would definitely need the Subs. I really viewed these as party speakers. Big and loud, but not refined.

With the vast distances between speakers, I would suggest looking into omni-directional speakers to fill in the gaps more fully. I use the Mirage OMD-28s, which are amazing and need no sub, and the OMD5s as surround. You could setup one hellova system with OMD-15s all around (the OMD-15 setup won HT speakers of the year in 2007). I haven't heard their surround speaker, but have read it's absolutely amazing. They do need some room off the wall for best sound. Worth a look at vanns.com as an option.

Good luck!
Mot
.
Terror, EXTREME is exactly what I'm after here. After reading all of the great input I've gotten here, I will integrate at least one pair of subs to help on the bottom end. I may wind up with four subs by the time I'm finished.

I saw The Dark Knight at an IMAX theater a few years ago, and I am on a quest to try and duplicate the incredible sound that I heard there. Hearing that sound system made me want to re-think everything.
.
Mitch4t, yes you should be able to dial down/EQ the bass from full range speakers, which should work ok for your sidewall seating arrangements you presently have. Perceived bass will still be strong near sidewalls where you sit, but weaker in center of room overall, and anywhere out from sidewalls/corners. This will help your diliema if neighbors are a problem with your room construction acoutical issues.
Also, your horn speakers you're considering should help immensely with your sidewall speaker and seating locations, since you have so much sidewall reflection and slap echo issues right now. Would also help to toe em en a few degrees. Yes, horns are your best friend here, and HIGHLY EFFICIENT DESIGNS FOR ADDED DYNAMICS ..all things equal. So, yes, I like horns for you. also Klipsch's are worth a consider as alternative if CV's don't work out for your liking for strictly HT dubties.
Another strong consideration to smooth out bass and get proper perspective and added pressense from the speaker system is to mount your front L/R speakers and rears up the walls! I'd like to see you get those speakers off the flooor for acoustics and as big as your screen is, will match better and offer for pressence and grandure to the sound, IMO - just like commericial cinemas. In fact, more you duplicate their setup's, closer you are likely to your goals.
Another thing, I've seen your setup for years. Don't know how you live with slap echo and first order reflection issue with present setup, and seeing a double image from screen in that huge right wall mirror!...YEIKES!!!
Have you considered a "long wall" setup for your HT system?
You could easily free up more space, and yet still have a massive screen and potent setup flipping your system "sideways" - and going with smaller but still very large and wide 2.4:1 widescreen setup. Whether you put the screen opposing mirror, or where mirror is now, either way will make the visual experience much better than it is now, and take the reflection you see out of equation! I'd probably lean toward putting screen opposing the mirror, however.
Acoustical performance from your seating positions would also be WWWWWWWWWWAAAAAAAY BETTER doing a long wall setup as well, cause no sidewall reflection problems to deal with, and a much more spacious sound, where you are heaing much much more of the direct sound from the main speakers, instead of simultaneous delayed reflections off sidewalls! It's a consideration I'd strongly choose for you, if you can't treat mirror and sidewall refletions. This is fact. Never the less, if you can't, yes horn speakers are likely best options for you, for what you're after. Also, ACTIVE horn speakers will be even more dynamic and powerful (e.g., what IMAX uses)
If you do go "long wall setup" at some point, and you would consider that option, it will also have added benefit of letting you free up much of the space for much needed decor, furnishing, and decoration considerations on the ends of the room! I simply think there's lot left on the table here for all aspects of the room, even if you never do acoustical treatments in the space.
Hope this helps.
In reading about your IMAX experience, you should take a look at speakers from Tom Danley. His speakers have been installed in IMAX theaters and he is now making speakers for the home theater environment.
One Def Tech Trinity should add bottom punch galore. Reasearch is fun; find out why its called the Trinity ;)
Front all you need are one set of Klipschorns or La Scallas.
You can get used commercial La Scallas for a grand. New for $6k. New KHorns add $2k.
Put your money in the Center channel(s). One above and one below the screen.
Obviously this room is big enough for 7.1 or 9.1 so some nice rears and sides but you dont have to go nuts.
Its all in the center and the sub.
One more suggestion; Room treatments. Hang some panels off the ceiling at various levels. IMO it would give the room a tech look in addition what you have going on now.
Sweet set up.
PS; By using a powered sub and super efficient fronts you dont need massive amplification. Put the $ in a nice Audessy (or type) HT Reciever. It will iron out many of the bugs in a room this size.
PPS; Put a La Scalla in the middle as well. Done !
They even can hang from the ceiling if you need to.