PDA

View Full Version : Could someone double check my design?



MakeshiftAudio
05-13-2009, 02:16 AM
I havn't designed ports into it yet, and I need help determining port length with a port area of 97.5", determined by 32.5"x3". From here I will finish the design. :) I would also liked the volume of the box as it is checked as well, the whole top plate is doubled.

http://img503.imageshack.us/img503/8819/cutsom2.jpg

It is for an APXX 18" running at 4kW.

TPSs from Atomic: TSPs in the normal format are posted a couple posts below.

* Loudspeaker Enclosure Analysis Program
* LEAP® EnclosureShop 5.1.0.334 Jan/25/2005
* ©1993-2003 LinearX Systems Inc
* Date: May 12, 2009 Tue 10:46 am
* LTD File=C:\Program Files\LEAP\Transducers\ATOMIC APXX.Ltd
* Electro Mechanical Parameters
Name= APX18D2.856.
Note=
Model= TSL
Domain= FreeAir
Shape= Round
Profile= Cone
Fmd= 3.0000 KA
Qmd= 1.0000
Flp= 8.0000 KA
Qlp= 2.0000
Znom= 4.0000 Ohm
Revc= 3.6000 Ohm
Sd= 125.0000E-3 M²
Mmd= 444.0000E-3 Kg
Pmax= 5.0000E3 W
Rtvc= 50.0000E-3 °C/W
Xgap= 30.0000E-3 M
Xcoil= 50.0000E-3 M
Xmax= 10.0000E-3 M
Krm= 120.0000 Ohm
Erm= 642.0000E-3
Kxm= 492.0000E-3 H
Exm= 474.0000E-3
Rms= 19.2875 N·S/M
Mms= 469.3975E-3 Kg
Cms= 12.3100E-6 M/N
Vas= 27.4725E-3 M³
Fo= 66.2095 Hz
Qms= 10.1243
Qes= 0.5041
Qts= 0.4802
BL= 37.3450 T·M
Levc= 4.9445E-3 H
SPLo= 93.8269 dB
No= 1.5166 %
* End

MakeshiftAudio
05-13-2009, 05:53 PM
Bump? Help anyone? This is going into a 2002 Nissan Altima.

MakeshiftAudio
05-13-2009, 07:32 PM
Sdfdsfsdf. No one? :|

cj407
05-13-2009, 07:36 PM
is it necessary to have that extra ~1.73 cubes added? with that funky design...could just do the box and eliminate that ~8x11x34 section that has the angles cut.

MakeshiftAudio
05-13-2009, 07:43 PM
Well, you tell me. Would it be better to run ~8 cubes net or ~6 cubes net for it? Or is the better question: Would it be okay to run it at 6 cubes?

Thanks for the help. :)

cj407
05-13-2009, 07:49 PM
cant tell...as the tsp's i've never seen written like that.

iamamp3pimp
05-13-2009, 07:53 PM
i think it would be ok @ 6 net, but I like the larger boxes...

MakeshiftAudio
05-13-2009, 08:12 PM
The TSPs are in standard SI unit format, not what you're used to. Let me rewrite them quick.

Domain= FreeAir
Shape= Round
Profile= Cone
Fmd= 3.0000 KA
Qmd= 1.0000
Flp= 8.0000 KA
Qlp= 2.0000
Znom= 4.0000 Ohm
Revc= 3.6000 Ohm
Sd= .1250000E-3 M²
Mmd= .444g
Pmax= 5000 W
Rtvc= .050 °C/W
Xgap= 30mm
Xcoil= 50mm
Xmax= 10mm
Krm= 120.0000 Ohm
Erm= .642
Kxm= 492.0000E mH
Exm= .474
Rms= 19.2875 N·S/M
Mms= 469.3975g
Cms= 12.3100E-6 M/N / .0000123100 M/N / 12.31 uM/N
Vas= .0274725E M³ / 27.4725 L (Is this right? O.O)
Fo= 66.2095 Hz (Wat. That's really high.)
Qms= 10.1243
Qes= 0.5041
Qts= 0.4802
BL= 37.3450 T·M
Levc= 4.9445E mH
SPLo= 93.8269 dB
No= 1.5166 %

The sub I have is a D1.4, but I forgot to specify it when I asked them for it. :\

Well, I'm trying to use as much trunk room as possible, and with taking that wedged area out, I would not being using room. Though I could now have an area to put crap... xD Though itt'd get pulverized with 4kW into this. I'll think about it. :) Does port firing into the seats sound okay? It has enough room to breath.

MakeshiftAudio
05-13-2009, 10:04 PM
Bump. Some advice would be appreciated. xD

If I go with just leaving that area off, and I put a port there, being 97.5"^2 port area, with the TSPs in the post above, starting with 7 cubes, how long should the port be to tune it to 36Hz?

DNick454
05-14-2009, 12:18 AM
That port is really skinny for how wide it is. I would try and make it a little taller and less wide to try and at least stay in the 1:8 range of width to height port ratio. It's just a rule of thumb, but it is like that for a reason, you get weird air volume to surface area friction issues when you go way over.

IDSkoT
05-14-2009, 12:23 AM
As a general rule, I like keeping the port ratio at least 9:1, but I hate passing 8:1. The more square, the better. Remember that.
As for the size, I'm unfamiliar with the driver. However, that Fs is pretty high, and that Vas doesn't seem right... I'm not really sure this is a good driver.

MakeshiftAudio
05-14-2009, 12:51 AM
Well, those TPSs seem really, REALLY odd. The TPSs on their site in .doc format say this:

UNITS APXX18D1
Revc (ohms ) 2.00
Fo (Hz) 38.34
Sd (sqM) .1195
Bl (TM) 26.88
SPLo (dB) 97.10
Xmax (mm) 10
Dvc (mm) 75.00

Qms (m.q.) 5.81
Qes (e.q.) .187
Qts (totQ) .181
Vas (liter) 112
Cms (uM-N) 55.2
Mms (gram) 312

I would say design off of this, though it's missing the impedances, though that is not needed for a box....Right?

As for port size, how about a 7.375"x15", resulting in 110.625"^2? I understand the surface friction concept, makes sense. :)

I really appreciate the responses guys! :veryhapp:

MakeshiftAudio
05-14-2009, 01:15 AM
Babump. Wanting to start construction on the box. :)