Building home theater sub - questions!

[behnkem]

yeas, i got a similar graph - I think my -3dB was at 39, not 32 though. Any input on the ports in WinISD anyone?

What program do you use, Omni?

Thanks for the input!
Mike

[Vikash]

What is the make and model of the driver you're using? Or give the full range of T/S parameters (and units) that WinISD requires and I'll measure it up for you.

[Bose(o)]

TL all the way! o wait, did you mention a size constraint? No? HORN! O wait, not that big? TL all the way! Did I say TL?

[toenail]

In winISD beta (alpha only lists solobaric) I only find two possible matches for the description you gave for your driver "Its a Comp 8" Kicker sub, 4ohm". (assuming the "C" means Comp)

Kicker C-8-4
and
Kicker C8C-4

Neither of them have T/S specs resembling the ones you posted. You'd be better off to get ALL the T/S specs and plug them in yourself, or better yet, measure them yourself and try it.

I've had great success with winISD modeling a sub for my home theater. There was no confusion about the ports. If you plug in the T/S specs and choose a ported configuration It'll tell you ideal box and port dimensions. Change the number of ports and it'll tell you the new dimensions for them. As you've probably figured out .182 is a bit short for the port. Try a larger diameter.

[toenail]

BTW,

when I modeled the C8C-4 to the box and ports you mentioned it says the port length should be .182 METERS, not inches. Click on the M next to port length to scroll through different units of measurment until you get to in. (came out to 7.17")

The C-8-4 models almost identically to the first (7.18") and has almost exactly the same response curve when overlayed.

[behnkem]

That would make sense - 7.17" not .182" - I was having a couple of problems of that sort when I first put the #s in making sure I used the correct measurement. You were right that it is the C8-4 Kicker.

Yep - my program shows the same. I don't know why I didn't try that - i think at first it was saying inches, and it musta got changed at some point.

Thanks!
Mike

(As far as the specs, my sub is an older model, so I'm not sure if the specs I have are right, or the ones in the program are - I am probably going to build a jig and use Speaker Tester program to check it out.)

[OMNIFEX]

Hey behnkem!

You see, all it took was those TS Parameters to get the
ball rolling.

The most I can tell you is use the TS parameters supplied
with your woofer. Alot of times they (Speaker companies)
update their specs, and, you will see two different TS chart
listings.

If your speakers came with a TS sheet, use that for reference.


The Program I use is Eminence Designner, and, Bass Box
Pro. The one I posted was the Eminence.

Best Regards,

[behnkem]

Thanks Omni and everybody for the responses.

I have one question left - if I use polyfill in the box, do I need to keep it up off the speaker in some manner? The speaker is a downward firing speaker, and I was concerned about the polyfill resting on it, especially while playing.

I was planning on covering the insides with foam to help the acoustics - will this help or is it unnecessary?

Thanks!
Mike

[behnkem]

Since you guys have been helping me out, I thought you may lilke a few pics to show the progress so far:

(I'll post the links so as not to take up a ton of room here)

http://www.moneyfromyourcomputer.com/screwed.jpg
http://www.moneyfromyourcomputer.com/painted.jpg
http://www.moneyfromyourcomputer.com/leg-oops.jpg
http://www.moneyfromyourcomputer.com/kickerC8.jpg

I have the ports done, (not attached, but holes and PVC pipe are both cut-pipe is painted(inside)) but I don't have the pics upoaded off the camera yet.

Mike

PS, the paint is just for the legs - I plan to cover with some carpet scraps I have.

[Brett D.]

Behnkem,


Here is a finish option that is both easy and cheap.. Go to Parts
Express and check out thier Vinyl Laminate
http://www.partsexpress.com/webpage....7&WebPage_ID=3

Available in Black Ash, Teak, Cherry, Beech and Textured Black.


Check out my DIY Sub (12" Sealed Stryke AV-12 Powered by a
500 Watt RMS Bob Carver Sunfire TDC Amp) 14" x 14" x 15"
which I temporarily covered with the PE Vinyl just so I didn't have
to look at naked MDF.. This stuff is no worse than what many
OEM speaker builders use!

My Sub: http://www.westol.com/~brettd/temp/mysub/

As for the Pollyfill and keeping it off of the driver, You could buy
some 3M Spray Adhesive and spray the side walls and top inside
with the adhesive and loosely affix the Polyfill to the walls to keep
it off and out of the drivers cone/motor.