WAF sub

[asiquis]

Negotiations are finally over --I hope!

I have attached a photo of the theater part of rec room which is 50' X 12'6'' X 7' 8"
You may be able to see the 8" sub in the left top corner and my failed attempt at camouflage for the rear centre speaker in the plant!

Here are the parameters from negotiations:
1) I/we? should have a new subwoofer
2) My wife shall not be able to see it.
3) I/we? can 1 sub that is on sale (tempest X)
4) I must use one of the BASH500 wpc rack amps that were given to me( -3dB at 23 and -9 dB at 18 Hz) at least for now until I can hopefully find a tweak to lower the high pass.

My idea is to have the entertainmentcentre continue to look pretty much as it is. The tweak will be to gut the bottom where the Oppo and the HD boxsit now and slide a subwoofer box in and then place the doors back on and a centre patch of some acceptable kind--maybe black grille cloth.

This being the case, I have exactly 53" of width and 22" of height and 25" of depth to work with.

Might I have some suggestions as to where to fire the 32" 8" port and where should the driver fire?
Port out one side facing the side wall and driver facing the other side wall?
Driver facing stright out to couch we sit on (screened by a grill cloth center) port facing?

How might I best brace this?
How much net volume might I be looking at?
Would fulling stuffing it help with more volumefor the Tempest X?

[Mike P.]

How might I best brace this?

"Window pane" internal bracing works fine.

How much net volume might I be looking at?

A little over 13 cubic feet.

Would fulling stuffing it help with more volumefor the Tempest X?

Yes, I believe so. I personally would go with a front firing sub and side mounted port.

[tundraSQ]

Forget the sub for now...you need to work on the viewing distance or upgrade to a bigger TV

j/k

[asiquis]

I have been thinking the same things, but my wife insists NO BIGGER TV...however, she did offer me a used pair of binoculars so it would appear bigger!
The set is a 42 inch vierra plasma and I am about 10 feet away--actually the set is about 10 feet away-- as I am always in the same place.... except when I am sitting closer....

[sparky77]

You could easily fit two Emminence Lab12's in that space as they only require about a half cubic foot per speaker in a sealed configuration, and use one amp for each sub.

[jerome]

One of Bryan's no-no rule about getting good sound (Link) is:
Don't put ANY speaker or sub that isn't specifically designed to be built in inside a cabinet or build it into a wall. You'll drastically change the response curve. The crossovers are specifically designed for a specific frontal area on the cabinet

If I were you, I would not try to buy manufactured sub(s) and put it below the TV. In addition, building a sub in your furniture will make your all 'entertainmentcentre' vibrates when using the sub. Or you need a LOT of demping inside...
I don't think that the DVD player and TVs will like that ...

What about hiding you new sub(s) below or back the sofas? Do you have enough space there?

[StephenP]

How about getting rid of the end table where the pink lamp is and build a sub to go there? You (or a carpenter) can make one that looks like furniture, it doesn't have to be an ugly black box.

[asiquis]

I had asked that question a short time ago on the forum "will subwoofer affect TV negatively" and got some different information so I am a little confused...but I am new to this and am willing to learn.

Would an isobarrik or other configuration using 2 drivers reduce cabinet vibration? I would be bracing well. The reason for the large box is that 15" Tempest X were on sale and the box would be invisible in that there would be false doors on it so the entertianment unit looks kind of the same as what is there now. I get flak now with having a little 8" sub in the left corner by the pink lamp--hence the idea to "hide" or camaflague... The new sub box to be built will have the upper part (where the TV is now) sit upon the new sub box-maybe some dampening material between the new sub box and the upper portion would help?

Open to suggestions.

[asiquis]

I was looking at that option when I found that the Tempest X was on sale which would mean a bigger box. I was also looking at the replacing the table that sits on the righthand wall with some kind of camaflaged subwoofer, but was thinking the best sound might come from putting the sub box between the main speakers?? Any thoughts?

[asiquis]

sparky77 wrote:

You could easily fit two Emminence Lab12's in that space as they only require about a half cubic foot per speaker in a sealed configuration, and use one amp for each sub.

I will see how that might look on WinISD...

[sparky77]

About .75 cu ft per sub if I remember correctly, I plan to build one in a sealed box, and experiment with another in low tuned ported enclosures.

http://www.partsexpress.com/pe/showd...number=290-570

They even have a pretty reasonable efficiency for the amount of xmax they're supposed to have.

[Warmon]

asiquis wrote:

IWould an isobarrik or other configuration using 2 drivers reduce cabinet vibration?

Yes and no, but you don't want to do isobaric unless the drivers are very inexpensive..you lose 6db over a single driver, whereas you gain 3db for each one you add. Push Push or back to back tightly coupled will cancel vibration.

[salvasol]

What about building the subs and using them as speaker stands???

[Mike P.]

In my opinion it would be hard to build a Tempest-X sub into the entertainent ceneter and have no vibrations affecting the TV and other electronics. Since the wife should not be able to see it, another option would be to place the sub behind the viewing couch out of sight. The box would be slightly wider and higher then the diameter of the sub, and long enough to provide the proper volume. Here's an example.

http://www.speakerbuilder.net/web_fi...ts/RT3/rt3.htm

[aceinc]

Using a different motif, try and run something like this past the spouse;

http://www.hometheatershack.com/foru...ub-system.html

Paul

[asiquis]

I now have the driver (Tempest X) it's bigger than the whole 8" BIC subwoofer that now resides in the corner

Looks like I will go with the sub placement underneath the existing entertainment unit.
400 liter box stuffed with about 80 oz of polyfill
500 wpc BASH with 13.9 Hz highpass
tuned to around 16-17Hz.
8" port around 30"

With the room size I do not get much if any room gain so I guess it is best to keep the tuning frequency up a little.

My question:
What is your opinion on which direction to face the driver and the port and why?

The box will be centred on the front wall under the TV (the TV will be attached to the wall -not sitting on the subwoofer ) dimensions of the box 49" wide 26" deep 24" high and the sides of teh box will be 48" from each side wall.

[collo]

You can also rip the bottom out of the entertainment unit and have a free-floating sub sitting on the floor. Leave a gap of about 1/2" between the side / top wall and the cabinet. Stuff the gap with a little bit of foam rubber, such as is used to seal around doors.

Mount the grille cloth on a frame that clips onto the entertainment unit. This will give the integrated appearance, but isolate the sub from the unit.

[StephenP]

I would be careful if removing parts of the entertainment center floor, it may add considerable strength to the design and the whole thing may crash down. Have you checked the port resonances on that vent? Sometimes you can make a pipe organ with big vents if you are not careful

How far will the sub box be from the back wall? I assume a couple inches at least to allow for the cables to plug in to the amp, but I would want at least 6" if there was a vent on the rear. It would seem that putting the driver and vent both on the front would be the easiest, but you are going to have to put an elbow in that vent to get 30". If you are still thinking of using this as an end table that would be the best solution, and you could put the vent on a side and not have to have the elbow.