Which is the better option accoustically

[m00n]

Here is a side view of two different general ideas. My mindset has always been on option B, but, is option A just as good if not better?

Ok, just to complicate things i feel design "A" would be better than "B" on several levels.

- More room for the port to breath

- Asymetrical configuration reduces possible resonances..

The biggest draw back, I my opinion, is your drawing skills. [] Ok, I'm not sure if it was intentional... but the reduced outlet on top of the speaker in design "A" is it's biggest drawback versus design "B". BUT, if "B" fits on that wall, nothing keeps you from raising the top in "A" to be in-line with design "B".

I see little reason not to go with plan "A"

Rob

I had a feeling that the symetrical config would reduce resonances. I do want point out one thing, I will have 6" of space on each side as well as behind the speaker to allow for breating. These images are not to scale at all. I just tossed them together to try and demonstrate the idea.

[Duke Spinner]

INDY has the best suggestion ...HANG "EM high

[DrWho]

Here is a side view of two different general ideas.

My mindset has always been on option B, but, is option A just as good

if not better?

Go with option B, but don't make it parallel to the back of your

speaker cabinet (this will make the slope of that cubby wall

taller/steeper). While you're at it, this looks like a perfect

opportunity to put in some dramatic lighting...on the "ledge" below the

speaker you could totally put some lights firing upwards and provide an

ambient glow (which would turn off when the movie starts of course).

Also, is this just going to be a square cutout in the wall (looking

directly at the speaker instead of a side view)? Don't forget that you

can make the hole wider than the speakers too (perhaps angle them a bit

as well). To make your job easier, you might consider cutting out a

hole similar in shape to A, and then add a piece of wood to create the

angle...perhaps use a piece of masonite which you can even curve a bit

(which looks really cool with special lighting and might have some

acoustical benefits).

[m00n]

DrWho,

If you were to look directly at the speaker, the wall cutout (cubby) will be 12" wider than the speaker, giving 6" of air. Here is a new drawing... Picaso aint got jack on my MS Paint skillz. []

[Bill H.]

m00n,

I will probably get Hell for this, but what does Ms m00n think of these plans?..............

[colterphoto1]

It seems like you're talking about butchering up a lot of wall to move a speaker 4" back. Is it really that tight in the room?

[m00n]

ms m00n does not care. My theater is not in my house. Our house came with an old 3 bay tractor garage that had been converted into somewhat of a living space. I'd never live in it but it's good enough for what I use it for.

1/3 is my kitchette office space

1/3 is my theater (which is in what would have been the middle bay)

1/3 is my shop.

Each section is isolated by walls.

[m00n]

It seems like you're talking about butchering up a lot of wall to move a speaker 4" back. Is it really that tight in the room?

Yes and if I didn't push the speakers into the walls, the surrounds would be only about 1-1/2 foot away from the listener.

The room is only 10 wide, I have 3 rows of 3 theater chairs. So, the chairs take up at least 6' of the 10 foot of width leaving bairly enough room as it is to walk around them.

Here is my website. These are old pics, back when I still had my RS7s. Imagine replacing the RS7s with the RC7s and thats how tight the room is. You can clearly see that I need to build some cubbies for them to sit in.

http://www.m00n.net/m00ncinemas/index.aspx

[Lurch]

Not to rain on your parade, but why not in-walls????

R-5800W is $750 per pair vice $800 per RC-7.

[m00n]

Hmmm... It may be nieve of me, but I always assumed that they would not sound as good as regular speakers. On top of that, I wanted to stay with the immediate R7 family.

[DrWho]

Ok, I did a little editing of your pictures...

you want to avoid having any parallel surfaces because they easily

resonate (the "boxy" sound comes from the fact that the surfaces are

parallel, hence the term from "box"). Your speaker cabinet is going to

vibrate, which will in turn excite the air surrounding it. If your box

has any form of resonance, the air is going to be easily excited and

muddy up the sound.

The picture of course exagerates a bit the attempt to avoid parallel

surfaces. Get this right and your probably won't need to put any

absorbtion around the speaker. I know it makes it harder to build

though....but that's why you have all that fancy equipment in your shop

(which you have chosen to purchase over speakers! blasphemy!)

I believe either setup is going to slightly lower the tuning point of

your speakers, but it shouldn't be a huge deal because you are going to

experience some baffle gain because the drivers will be closer to the

wall. Btw, have you figured out which woofer has the tapered array

(which one only plays the low notes). I would think you would want to

get all your surrounds lined up relative to each other (probably with

the midrange woofer closer to the cieling as it is further out of the

hole).

[Lurch]

I don't doubt that the RC-7 sounds better when properly situated, but it seems like we've exited that territory. The installation you are describing is what in-walls are designed for. It might be worth your time to go down to the Klipsch dealer and compare the two, but with the RC-7s butted up against the wall.

[m00n]

DrWho

Thanks for the redesign idea. It wont be a big deal to go with your approach. A little more work but not that big of a deal.

Hey, I have all the speakers I need, buying shop equipment seemed like the next logical step. []

The low frequency driver is the left driver if looking at the front of the RC7. My thought was that I would put low frequency on the bottom just as you suggested.

[DrWho]

With all your fancy shop equipment I still ask myself why you don't just build new cabinets for your RC-7's and move the ports to the front []

Weren't you considering some form of cabinet rebuild a while ago? (like a top mounted port so you could make the speaker wider and narrower to fit your application better).

[m00n]

With all your fancy shop equipment I still ask myself why you don't just build new cabinets for your RC-7's and move the ports to the front []

Oooohhh.. Cause that would be the SMART thing to do. []

Weren't you considering some form of cabinet rebuild a while ago? (like a top mounted port so you could make the speaker wider and narrower to fit your application better).

Yes I was. But I could never figure out the dimenions. I wanted something that had a tilted face, was not as tall, that had the drivers side by side with the horn on top of them. Something like this.

[m00n]

I also have this forumla to go by, but there was some information I was trying to gather, but could not seem to get it for some reason.

[D-MAN]

Cabinet diffraction (the soundwaves follow the cabinet all the way to the back) is the problem that you will experience in EITHER of your approaches.

The hollow behind the cabinet is going to be a problem and the only way to prevent it is to NOT have a hollow behind the cabinet. Sealing along the outside edge would prevent diffraction into any hollow, of course.

Barring that, size the wall "cutout" as close to the cabinet size as possible and follow the cabinet contours.

An alternative is to FLUSH mount the cabinet in the wall (flat 90 Deg.) if you can get the dispersion the way you want it.

Another approach which is most used professionally is to use an angled speaker cabinet in the first place.

DM

[DrWho]

Cabinet diffraction (the soundwaves follow the

cabinet all the way to the back) is the problem that you will

experience in EITHER of your approaches.

The hollow behind the

cabinet is going to be a problem and the only way to prevent it is to

NOT have a hollow behind the cabinet. Sealing along the outside edge

would prevent diffraction into any hollow, of course.

Barring that, size the wall "cutout" as close to the cabinet size as possible and follow the cabinet contours.

An alternative is to FLUSH mount the cabinet in the wall (flat 90 Deg.) if you can get the dispersion the way you want it.

Another approach which is most used professionally is to use an angled speaker cabinet in the first place.

You're forgetting that the RC-7 is a rear ported enclosure - m00n has

been around this bush many a time now and has yet to decide on a path

to take - it is kinda funny reading all the suggestions of those not

familiar with his whole situation (gosh, this project is prob a year

old at least by now) []

[DrWho]

With all your fancy shop

equipment I still ask myself why you don't just build new cabinets for

your RC-7's and move the ports to the front []

Oooohhh.. Cause that would be the SMART thing to do. []

Weren't

you considering some form of cabinet rebuild a while ago? (like a top

mounted port so you could make the speaker wider and narrower to fit

your application better).

Yes I was. But I could never

figure out the dimenions. I wanted something that had a tilted face,

was not as tall, that had the drivers side by side with the horn on top

of them. Something like this.

Ya know, if you went with what you drew in the picture, you could

totally get rid of the tapered array crossover (because the woofers

will be close enough together). There might be a slight narrowing of

the polar response, but this would be good in your situation (where in

your small room high directivity is a must). I bet Dean would be dying to get a hold of those crossovers []

Speaking of your room, have you gotten around to any new acoustical

treatments? I was thinking the RPG Skyline diffusors would go great on

your cieling. I bet it'd really help open up your sound.

Btw, why don't you do both approaches? Flush mount the speaker in the

wall AND build a new cabinet. That'll make the depth of the speaker a

little less critical and you'd get the best of both worlds.

[D-MAN]

Cabinet diffraction (the soundwaves follow the cabinet all the way to the back) is the problem that you will experience in EITHER of your approaches.

The hollow behind the cabinet is going to be a problem and the only way to prevent it is to NOT have a hollow behind the cabinet. Sealing along the outside edge would prevent diffraction into any hollow, of course.

Barring that, size the wall "cutout" as close to the cabinet size as possible and follow the cabinet contours.

An alternative is to FLUSH mount the cabinet in the wall (flat 90 Deg.) if you can get the dispersion the way you want it.

Another approach which is most used professionally is to use an angled speaker cabinet in the first place.

You're forgetting that the RC-7 is a rear ported enclosure - m00n has been around this bush many a time now and has yet to decide on a path to take - it is kinda funny reading all the suggestions of those not familiar with his whole situation (gosh, this project is prob a year old at least by now) []

Why on earth would someone use a rear-ported speaker in such a manner? I NEVER would have suspected that.

Seems like EXACTLY the wrong tool for the job.

DM