Tuning Parameters for the 12" enclosure

angelopb · #1 09-11-2012, 10:23 AM

I have the recently purchased the passive 12" tube. I kind of need to know the port length and diameter and volume for T/S parameters.
I am replacing the driver and adapting the enclosure for use as highly portable and efficient bass guitar cab. I love this driver and this obviously is not what the enclosure is designed for.
But any help would be appreciated. Hopefully, SAS will expand into pro sound with a line of portable speakers.
I am wondering if the port length needs to be trimmed to bring up the tuning frequency to 48hz.

The T/S paramaters are

Resonant Frequency (fs)
48Hz
DC Resistance (Re)
5.1
Coil Inductance (Le)
0.43mH
Mechanical Q (Qms)
5.5
Electromagnetic Q (Qes)
0.53
Total Q (Qts)
0.48
Compliance Equivalent Volume (Vas)
91 liters / 3.2 cu. ft.
Peak Diaphragm Displacement Volume (Vd)
270cc
Mechanical Compliance of Suspension (Cms)
0.24mm/N
BL Product (BL)
11.7 T-M
Diaphragm Mass inc. Airload (Mms)
46 grams

Efficiency Bandwidth Product (EBP)
91

Maximum Linear Excursion (Xmax)
5.2mm
Surface Area of Cone (Sd)
519.5 cm2
Maximum Mechanical Limit (Xlim)

9.8mm

Geneh · #2 09-12-2012, 09:35 AM

The Bazooka enclosure design is what makes the subwoofer so efficient. (more dB per watt)
Do to company policy we can not give any type of specs or help in modifying the cabinet.

angelopb · #3 09-13-2012, 10:05 AM

Tha's fine. The Emience driver seems to work fine. It is not bottoming out or anything. I am more interested in controlling the resonance. I have applied some dampening material to the surfaces but it is still vibrating heavily on the lower notes of the bass guitar starting with low A. I am going to look into a way to brace it. Is port noise normally audible. I understand that when corner loaded in a trunk it may not be. But Im trying to figure out if that is inherent in the enclosure or is there something else? Also, is there a reason the grill is plastic?

Geneh · #4 09-13-2012, 10:57 AM

Are you hearing the noise just on the lower notes or all the time? Also did you leave the insulation in the cabinet?

As for the plastic grill, we used a metal mesh grill in the beginning. The mesh grill would bend when hit and would have to be removed to be straightened. We had allot of complaints about how hard it was to remove the mesh grill. The plastic grill is easy to remove, has less restriction of the air flow and holds its shape better.