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  #11  
Old 10-30-2009, 07:22 PM
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Originally Posted by Inertia View Post
How would a sealed sub sound in a box that has a Qtc of 1.01?
Not at all good if you use it straight. If you have a powerful tonal shaping device such as a DCX2496, then you can get a smooth, highly damped response via electronic signal correction.

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  #12  
Old 10-31-2009, 11:53 AM
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First off it has a low efficency bandwidth... 34 which is much lower than the AW121T I might add... Which to my knowledge makes it good in a sealed enclosure.
Run the numbers yourself:
Fs 33.5hz
Qts .876
Qes .973
Qms 8.852
Vas 75L or 2.64 cu. ft.
Re 3.31 ohms
Le 12.54 mh
Xmax +/- 11mm
RMS 650 watts
Efficiency 94db

I believe those parameters are all that is needed for winisd.
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  #13  
Old 10-31-2009, 02:01 PM
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Originally Posted by Inertia View Post
First off it has a low efficency bandwidth... 34 which is much lower than the AW121T I might add... Which to my knowledge makes it good in a sealed enclosure.
Run the numbers yourself:
Fs 33.5hz
Qts .876
Qes .973
Qms 8.852
Vas 75L or 2.64 cu. ft.
Re 3.31 ohms
Le 12.54 mh
Xmax +/- 11mm
RMS 650 watts
Efficiency 94db

I believe those parameters are all that is needed for winisd.
It is a lousy driver. A classic car thumper.

Name: AW150T
Type: Standard one-way driver
Company: Audiobahn
Comment: Excursion series
No. of Drivers = 1
Fs = 30.6 Hz
Qms = 5.92
Vas = 95 liters
Cms = 0.119 mm/N
Mms = 219 g
Rms = 7.388 kg/s
Xmax = 10 mm
Xmech = 15 mm
P-Dia = 309 mm
Sd = 750 sq.cm
P-Vd = 0.75 liters
Qes = 0.59
Re = 3.2 ohms
Le = 2.1 mH
Z = 4 ohms
BL = 15.11 Tm
Pe = 600 watts
Qts = 0.54
no = 0.445 %
1-W SPL = 88.63 dB
2.83-V SPL = 93.9 dB
-----------------------------------------
Box Properties
Name:
Type: Closed Box
Shape: Prism, square
Vb = 1.804 cu.ft
Qtc = 0.707
QL = 18.26
F3 = 49.47 Hz
Fill = heavy

It has a high F3 and can not be equalized as it is very power limited in the bass.

At 30 Hz it can only handle about 30 watts!
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  #14  
Old 10-31-2009, 04:10 PM
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Quote:
Originally Posted by Inertia View Post
First off it has a low efficency bandwidth... 34 which is much lower than the AW121T I might add... Which to my knowledge makes it good in a sealed enclosure.
Run the numbers yourself:
Fs 33.5hz
Qts .876
Qes .973
Qms 8.852
Vas 75L or 2.64 cu. ft.
Re 3.31 ohms
Le 12.54 mh
Xmax +/- 11mm
RMS 650 watts
Efficiency 94db

I believe those parameters are all that is needed for winisd.
I still don't see where you indicated which driver it is. From your comment about lower efficiency bandwidth being lower than the AW121T, I have to assume you wanted to know about the 15", but...

It's not terrible in a sealed enclosure but there are others that do better.
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  #15  
Old 11-02-2009, 01:53 PM
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Bandwidth efficiency is just a number denoting natural response tendencies. It really does not tell you anything about a driver's suitability in reality. Fact is, a sealed enclosure needs VERY long stroke with high linearity to have high performance in sub-bass frequencies. Almost every serious sealed application will also be using electronic signal correction, therefor, natural response of the driver is irrelevant. The W7 based JL audio systems for example, would have very little extension under 45Hz without electronic signal correction.

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Last edited by WmAx : 11-02-2009 at 02:02 PM.
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  #16  
Old 11-03-2009, 02:32 PM
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Interesting... so even the W7 has trouble with low frequencies in a sealed enclosure. I have a kappa perfect... guess I just want to try something new!
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  #17  
Old 11-03-2009, 03:35 PM
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Originally Posted by Inertia View Post
Interesting... so even the W7 has trouble with low frequencies in a sealed enclosure. I have a kappa perfect... guess I just want to try something new!
Correct every driver rolls off in a sealed enclosure. This is why we build ported subs usually.
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