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View Full Version : Drew up a little design for my E8's... (to scale)



Rawr-DQ
05-23-2010, 12:52 PM
http://i130.photobucket.com/albums/p254/Totalnewbie007/IMAGE_097.jpg

Specs are per 8 subs 1/2 of the box, I used bb6 to calculate a box prism w/ a truncated edge, and basically doubled it and put both sides on top one another.

Fb is actually the f3 on the picture, and the calculated fb for three 34" long 2"x10.58" ports @ 2.392 cubes is 45.26, but I did not take into account the flared aspect of the alligator mouth style of this box, but added it's length to the port length...so its kind of a mystery.

O.G. D-Wet
05-23-2010, 12:56 PM
design looks pretty gnarly! Whenever I scoop up my ride im tryn to do like 4-6 SA-8s in a similar config

Flastrongman
05-23-2010, 01:23 PM
Hey I know you, you're Charlies friend. I heard your 16 8's over at Danny's house some time ago. Changing it up again eh?

Rawr-DQ
05-23-2010, 01:31 PM
Oh yeah, haha, This one should be the loudest! This will be my 3rd 16 e8 box, and my 6th major rebuild overall in the stratus

on1wheel01
05-23-2010, 01:34 PM
That would be sweet

Rawr-DQ
05-23-2010, 01:42 PM
This was my old clamshell
http://img234.imageshack.us/img234/7299/misc12010jn5.jpg

http://img356.imageshack.us/img356/3571/misc12001px1.jpg

http://img527.imageshack.us/img527/9259/misc13003kw1.jpg

http://img266.imageshack.us/img266/3363/misc14011ek4.jpg

http://i130.photobucket.com/albums/p254/Totalnewbie007/DSC02683a.jpg

O.G. D-Wet
05-23-2010, 01:51 PM
Vids!!!!!!!!!!!!!!!!!!!!!!

Rawr-DQ
05-23-2010, 01:57 PM
Keep in mind this is the old box.



misc15006.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15006.flv)

misc15008.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15008.flv)

misc15010.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15010.flv)

misc15011.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15011.flv)

misc15012.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15012.flv)

misc15013.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15013.flv)

O.G. D-Wet
05-23-2010, 02:11 PM
Keep in mind this is the old box.



misc15006.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15006.flv)

misc15008.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15008.flv)

misc15010.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15010.flv)

misc15011.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15011.flv)

misc15012.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15012.flv)

misc15013.flv video by Totalnewbie007 - Photobucket (http://s130.photobucket.com/albums/p254/Totalnewbie007/?action=view&current=misc15013.flv)

Wouldnt the SA-8s suit your needs a little better than e8s?

Rawr-DQ
05-23-2010, 02:16 PM
They weren't around then, and they're deeper making it impossible to fit in this box. If I had sa 8s I'd do a wall.

Flastrongman
05-23-2010, 02:25 PM
What was the best score you've gotten out of those 8's so far?

O.G. D-Wet
05-23-2010, 02:27 PM
They weren't around then, and they're deeper making it impossible to fit in this box. If I had sa 8s I'd do a wall.

u wont do it... :rolleyes:

Rawr-DQ
05-23-2010, 02:31 PM
u wont do it... :rolleyes:

You're right, I wont, I don't have the money. If I did anything I'd get 18's with as much xmax as possible and build a ported box tuned to 15-20hz.

I never metered the box, but I think it was mid 140's, the new one should be the old clamshell on roids, the second box wasn't as loud because of cancellation issues I don't completely understand.

O.G. D-Wet
05-23-2010, 02:40 PM
You're right, I wont, I don't have the money. If I did anything I'd get 18's with as much xmax as possible and build a ported box tuned to 15-20hz.

I never metered the box, but I think it was mid 140's, the new one should be the old clamshell on roids, the second box wasn't as loud because of cancellation issues I don't completely understand.

****, is than an issue with the clamshell design itself? I'm interested in doing a clamshell enclosure for four 8s... I thought I could just get the internal demensions right and just slap it together but I guess there's more to it than i thought

Rawr-DQ
05-23-2010, 02:45 PM
No the clamshell was the first box, it was the loudest, just not loud enough for me, and it seems the stratus isnt easy to get loud. My second box was just a wedge with all 16 on one plane. Clamshells are interesting, and have some dynamics I don't understand completely, the angle you have your speakers affect its output, however I'm not sure if the opening was larger making the speakers closer to a 90 degree angle would greatly improve output.

O.G. D-Wet
05-23-2010, 02:53 PM
someone should def do a write-up on clamshells (if there isnt already one)... It would make a very interesting read. So would you suggest just sealing the SA-8s at the trunk ported on a shared plane or you think I'll be fine with the clamshell? (a LOT less than 16 subs lol)

Like do u think the clamshell would be worth the extra work?

Rawr-DQ
05-23-2010, 03:04 PM
The reasoning I have for a clamshell is the fact I can not fit 16 8" subs on a single plane in my car without doing a wall. With the first clamshell I was able to keep all my seats and have the subs firing forward.

Rawr-DQ
05-23-2010, 03:08 PM
Found a snippet of info on clamshells...however this might pertain more to mounting two speakers together to act as a single speaker aka isobaric loading

About isobaric enclosures...

Again this is not a new concept, having been originally introduced by Harry Olson in the early 1950's. Technically, "isobaric" is not really an enclosure type; it is a loading method. This loading method involves the coupling of two woofers to work together as one unit. This is typically accomplished either by placing two woofers face to face or by coupling two woofers with a small chamber. The result of coupling the two speakers is that the coupled pair (iso-group) can now produce the same frequency response in half the box volume as a single speaker of the same type would require. For example, if a speaker is optimized for performance in a 1 cu.ft. sealed enclosure, one iso-group of the same speakers can achieve the same low frequency extension and overall response characteristics in a 0.5 cu.ft. sealed enclosure.

There is, of course, a penalty involved. Whenever you use isobaric loading, you are sacrificing 3dB of efficiency compared to a single driver in twice the air space. In practical terms, this is not usually a big deal since the powerhandling is doubled (two speakers instead of one) so the end result is about the same output as the single driver in the bigger box assuming you double the amplifier power.



Isobaric loading can be used within any enclosure type, including bandpass designs. The ported and bandpass isobaric designs can be difficult to design and build due to very small enclosures with large port requirements. Isobaric bandpass designs, in particular, can be literally impossible to build with certain speakers. There are some things to look out for with each type of isobaric design, such as mechanical noise and uneven heat dissipation which can present potential sound quality and reliability problems. All the methods which involve opposite cone motion require that the speakers be wired in reverse polarity relative to each other. These designs also provide a performance advantage in that their opposed cone motion averages out suspension non-linearities (differences in inward and outward suspension control,) which reduces distortion.

If you are strapped for space and can afford the extra speakers and more complex enclosure, the ability to have a compact subwoofer system with no real sacrifice in performance is well worth the extra effort and expense. On the other hand, if you have a lot of space and are looking to get the maximum amount of output without sacrificing sound quality, using multiple iso-groups can give you the best cone area/box volume ratio while still retaining good fidelity. Isobaric loading is not as popular today as it was in the early days of car audio subwoofer design. Why? Today's car audio woofers are designed for much smaller enclosures than their forebears, making the need for isobaric loading rare.

O.G. D-Wet
05-23-2010, 03:28 PM
yea, DEF not trying to do an iso... maybe if I hit the lottery I'd do like 8 21" DPs iso just because I could lol