my buddy gave it to me in his garage sale and i have NO clue about this thing. he doesn't have the box or anything. So i had a generic ported box and put it in there, hooked up a amp, bridged the amp cuz it was one of those 4 channel 1200 watt ebay ones (so now its sending about 400-450 watts im guessing to the sub).

sound is so minimal, doesn't hit, it just moves around. The box isn't sealed and it blows... im guessing that's the problem so im going to build a new box that IS sealed and has all the proper dimensions.


which brings me to my main questions:
1) My sub has this "dual power terminal" crazy **** goin on (as seen in the picture). instead of me bridging the amp - couldn't i just hook it up to my amp in 2 spots, like as if i had to subs? so "double the power" is going to the sub? or is that to wire in parallel or whatever to an additional subwoofer?

2) the specs given to me by http://www.lightav.com/car/planet/sub.html is that it has
# Power Handling (Peak) 400 Watts
# Power Handling (RMS) 200 Watts
# Frequency Response 25 Hz to 2500 Hz
# Efficiency (1 Watt /1 Meter) 91 dB
# Impedance 4 Ohm /Dual 4 Ohm
# 2" Aluminum Voice Coil
# Stamped Steel Basket
# Magnet Structure 60 oz.
# Mounting Depth 5-1/8"

what cubic foot sized box should i build?


Modified by tegasaurus at 3:57 PM 10/16/2005

 

the box i have now, is greater than 1.8333 cubic feet and is ported... si that the problem?

 

The term. set up is just what you think it is, one set it to wire from the amp the other is for another speaker, [PARA-TERM] according to http://www.dragondistributing....s.htm

Without the subs Theile-Small parameters it's hard to say what size the box should be, you might be able to find out from a place that sells them or if you can get Planet Audio's home site. 94

 

hrm, well i made a smaller box... sounds worse ithink haha..

what does mounting a sub backwards do for sound performance if anything?

 

Asuming that it's a Planet Audio V12D a sealed box should be 1.481 cu ft.
Vented = minimum of 1.776 cu ft with a 4x11.22 in vent. Will produce some noticeable vent noise though. An optimal "noise free" vent shoud be 5.284x21.28 in, but that's a hell of a pipe
An optimal vented box: 7.243 cu ft, 5x8.335 in vent.
Group delay in a vented box will be terrible- over 30 ms.

fcm, correct me if I'm wrong, but it looks like it's a free-air sub:
high sensitivity, low excursion, low Fs, huge VAS (for a 12 inch)...
Even though it looks pretty good in a sealed box too

Vas [Liters] 145,908
Qts 0,486
Qes 0,62
Qms 2,016
Fs [Hz] 29,64
Sensitivity [dB] 90,3
Max Power [W] 250
xmax [mm] 10
Moving mass [g] 64,237
Disp area [m2] 0,049
Cms [mm/N] 0,423845
Re [ohm] 1,8
Z [ohm] Dual 4 ohm
L [mH] 0,274
Bl [Tm] 5,613

 

If the T/S are correct, yes it sounds like they are free airs, although I think we are dealing with a SVC sub, you show the T/S for a DVC but I'm not sure.
The pix he shows are 12" subs the specs are for the 10" sub, and according to the specs, [limited] the 12" has an efficiency of 92 dB, not the 90.3 that you show so I am lost, without knowing the exact model he has, and the T/S for that sub, we are just guessing.

That said, whether it's a 10" or 12" if it that series of Planet Audio subs "free air" you would think that they would mention it at the site he links or the one I found, and I'm not sure the ones I found are the correct ones, I am not familiar with brand so I would want to know the exact model number and have Planet Audio's home page, access to there tech support. 94

 

fcm, u're right of cource, we have to know an exact model no. The picture shows V12S/D, though.
T/S parameters were taken from here:
http://www.thielesmall.com/database.asp