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RedDiamond
07-16-2013, 01:52 AM
Would anyone be able to help me with this design? It's for a single 15". I need it 3.5 @ 35htz, and no more than 19" in depth. All the designs I have found, have either been taken down, or are poorly made. If anyone could help me, that would be great, thanks.

hispls
07-16-2013, 01:58 AM
You shouldn't be planning on running a 15 tuned to 35hz if you don't have about 9 cube gross to work with. It's too small for a 15" and too small to tune that low with adequate port area without taking up a lot of volume.

Silverado SS
07-16-2013, 01:58 AM
Should be able to find one here
*OFFICIAL* Free Ported Box Plans (56k NO!!) - SRT Forums - SRT4, SRT6, SRT8, SRT10 & Dodge Forum (http://www.srtforums.com/forums/f40/official-free-ported-box-plans-56k-no-435910/)

RedDiamond
07-16-2013, 02:00 AM
You shouldn't be planning on running a 15 tuned to 35hz if you don't have about 9 cube gross to work with. It's too small for a 15" and too small to tune that low with adequate port area without taking up a lot of volume.

I'm going by what is reccomended for the sub.

RedDiamond
07-16-2013, 02:03 AM
Should be able to find one here
*OFFICIAL* Free Ported Box Plans (56k NO!!) - SRT Forums - SRT4, SRT6, SRT8, SRT10 & Dodge Forum (http://www.srtforums.com/forums/f40/official-free-ported-box-plans-56k-no-435910/)

Thanks Silverado, but the closest they have on there is 3.5 @ 32htz.

hispls
07-16-2013, 02:12 AM
I'm going by what is reccomended for the sub.

Cool. Stop back and give us some Termlab scores or an RTA graph.

n8skow
07-16-2013, 11:33 AM
9 cubes?!
It's a single 15...


You shouldn't be planning on running a 15 tuned to 35hz if you don't have about 9 cube gross to work with. It's too small for a 15" and too small to tune that low with adequate port area without taking up a lot of volume.

RangerDangerV2
07-16-2013, 11:46 AM
You shouldn't be planning on running a 15 tuned to 35hz if you don't have about 9 cube gross to work with. It's too small for a 15" and too small to tune that low with adequate port area without taking up a lot of volume.

I disagree.

PSturmer
07-17-2013, 12:48 AM
RE AUDIO - Box Calculator (http://reaudio.com/box.php)

n8skow
07-17-2013, 09:21 AM
RE's box calculator would be a good example of one 'not' to use...
It's results are not accurate.

hispls
07-17-2013, 07:24 PM
9 cubes?!
It's a single 15...

OK, that may be a little high, but consider about 2.5 cube for wood and bracing, .25-.4 cube for sub, then 1-2 cube for port. Whatever. Personally if I only had 3.5 cube to work with I'd be using a 12.

RangerDangerV2
07-17-2013, 07:25 PM
OK, that may be a little high, but consider about 2.5 cube for wood and bracing, .25-.4 cube for sub, then 1-2 cube for port. Whatever. Personally if I only had 3.5 cube to work with I'd be using a 12.

op is talking about net vol im assuming.

hispls
07-17-2013, 09:54 PM
op is talking about net vol im assuming.

In 3.5 net I'd be on the fence between 10 and 12" In testing in 3.5 cube I meter higher with a 10 in the same box (same motor, softparts)..... of course excursion becomes a problem outside of tuning so I'd possibly do a 12 depending how much power was on tap.

RangerDangerV2
07-17-2013, 09:58 PM
In 3.5 net I'd be on the fence between 10 and 12" In testing in 3.5 cube I meter higher with a 10 in the same box (same motor, softparts)..... of course excursion becomes a problem outside of tuning so I'd possibly do a 12 depending how much power was on tap.

we do 53's on music with 3.5 per chamber with many different types of 15s here in MN in a little red ranger.. 3.5 IMO is optimal for most 15s.
3

hispls
07-17-2013, 10:49 PM
we do 53's on music with 3.5 per chamber with many different types of 15s here in MN in a little red ranger.. 3.5 IMO is optimal for most 15s.
3

I'm sure that same vehicle would do the same numbers with 12's in the same box then. Smaller box = less output and steeper peak. 3.5 is generally MINIMUM for most 15's and IMO most manufacturers only just say that because people have their heart set on big subs to impress their buddies and won't know any better when the see the "recommended" specs. Kicker "recommends" 6 cube for solo X 18. Give that a whirl and let me know how that plays out.

n8skow
07-18-2013, 09:17 AM
Relatively steeper peak - yes, but to say less output is a bit of an overgeneralization. There are several 15's that would be plenty happy in 3.5 cubes (woofers with high qts and low FS). The enclosure sizes you are throwing around sound like you are referring to a 'specific' woofer though - (after reading over the thread again - there's been no mention of what the OP is using...)


Smaller box = less output and steeper peak. 3.5 is generally MINIMUM for most 15's and IMO

hispls
07-18-2013, 10:38 AM
Relatively steeper peak - yes, but to say less output is a bit of an overgeneralization. There are several 15's that would be plenty happy in 3.5 cubes (woofers with high qts and low FS). The enclosure sizes you are throwing around sound like you are referring to a 'specific' woofer though - (after reading over the thread again - there's been no mention of what the OP is using...)

List off a few 15's that do better in 3.5 cube than at 4.5. If OP is asking, chances are the box won't be big enough. I've used some 15's in boxes that small and in larger boxes and they're invariably louder and have a wider bandwidth than in the smaller boxes.

RangerDangerV2
07-18-2013, 10:40 AM
List off a few 15's that do better in 3.5 cube than at 4.5. If OP is asking, chances are the box won't be big enough. I've used some 15's in boxes that small and in larger boxes and they're invariably louder and have a wider bandwidth than in the smaller boxes.

nsv2, IA warden, IA dp, cascade omega

OldManBass
07-18-2013, 10:48 AM
nsv2, IA warden, IA dp, cascade omega

Hmm... IA told me their subs liked boxes on the larger end of the spectrum...

RangerDangerV2
07-18-2013, 10:50 AM
Hmm... IA told me their subs liked boxes on the larger end of the spectrum...

they work great in 3.5. the 15s that is.

Dirtrider4eva
07-18-2013, 10:59 AM
Op if you want a design for your sub pm me and ill handle it all..

RangerDangerV2
07-18-2013, 11:07 AM
Op if you want a design for your sub pm me and ill handle it all..

inb4129.9

n8skow
07-18-2013, 12:05 PM
I assume you are being facetious for the point of continuing this argument, but if you are actually looking for a few:
Z series or NS series from Sundown, Mojo's from Memphis, SSA DCON's, Fi Q, JL w3's and w6's...

My point was there has been no mention anywhere of the woofer in question - and just throwing out enclosure specs is a waste of time without knowing what speaker we are talking about building for here.

@RedDiamond - please enlighten us...


List off a few 15's that do better in 3.5 cube than at 4.5. If OP is asking, chances are the box won't be big enough. I've used some 15's in boxes that small and in larger boxes and they're invariably louder and have a wider bandwidth than in the smaller boxes.

RedDiamond
07-18-2013, 02:21 PM
Sorry, I guess I forgot to mention the speaker. It is a SEX15D2, the reccomended specs were between 3-4 cu ft - 34-35hz. I was just going by the reccomended because I couldn't find any information on what's better for that paticular speaker.

-BenBen-
07-18-2013, 02:24 PM
i like 4-4.5 cu for a 15.. jmo

n8skow
07-18-2013, 02:24 PM
version 1 or 2?


Sorry, I guess I forgot to mention the speaker. It is a SEX15D2, the reccomended specs were between 3-4 cu ft - 34-35hz. I was just going by the reccomended because I couldn't find any information on what's better for that paticular speaker.

RedDiamond
07-18-2013, 02:29 PM
version 1 or 2?

V1 I believe.

n8skow
07-18-2013, 02:55 PM
Do you happen to have the T/S specs for it?
They have the SRX info listed for the *** on the website, lol.



V1 I believe.

RedDiamond
07-18-2013, 03:02 PM
Do you happen to have the T/S specs for it?
They have the SRX info listed for the *** on the website, lol.

Yea I saw that too, though I do not..

RedDiamond
07-20-2013, 11:11 PM
Do you happen to have the T/S specs for it?
They have the SRX info listed for the *** on the website, lol.

Boom..
*** 15" T/S Parameters:
•Electrical Q Value (Qes): 0.55
•Mechanical Q Value (Qms): 4.3
•Total Speaker Q Value (Qts): 0.49
•Free Air Resonance (Fs): 22 Hz
•Equivalent Compliance (Vas): 209 liters
•One-Way, Linear Excursion (Xmax): 18 mm
•Efficiency (SPL 1W/1m): 88 dB SPL
•Effective Piston Area (Sd): 810 cm2
•DC Resistance (Re): 2.8 ohm
•Nominal Impedance (Znom): Dual 2 ohm
•Thermal Power Handling (Pe): 600 W
•Force Factor (Bl): 17.7

n8skow
07-21-2013, 09:18 AM
So is it just the wrong title on the specs sheet?
Based on those specs, I'd aim between 3-3.5 cubes (plus woofer/port displacement)

RedDiamond
07-22-2013, 02:19 AM
So is it just the wrong title on the specs sheet?
Based on those specs, I'd aim between 3-3.5 cubes (plus woofer/port displacement)

I got that info from another site. Yea, that's why I was looking for 3.5 @ about 35

RedDiamond
07-22-2013, 02:39 PM
Alright, back to the original question, with the port being so stretched out, would this design be possible at 3.5 @ 34-35hz?

http://img812.imageshack.us/img812/2915/6mqz.png

n8skow
07-22-2013, 02:44 PM
I'd avoid that wide skinny port - push the woofer over to one side - and port on the other.

http://farm8.staticflickr.com/7320/9343254523_5b0477291f_o.jpg