# having some fun w/ some old gear...



## Brute71 (Jun 6, 2012)

I have some rockford fosgate punch p1s4-8 subwoofers laying around here that I have no personal use for due to their characteristics. So I plan on building a burp box to see what they can do! Plan on powering them with a PPI amp that can dish out 1000w @ 2ohms easy, test out that 400w peak claim 

Initial box design with winISD im seeing 1.5 cuft tuned to 50hz w/ 2 .068m dia vents that are .101m long, could use some help fine tuning that however. Current gain is 6.84db @ 53.37hz.

Main goal of this little project isnt to potentially destroy a pair of subs, its a learning experience for me on designing and building a ported enclosure.

Fs (Hz): 39.0
Re (Ohms): 3.75
Le (mH): 3.0
Qts: 0.47
Qes: 0.53
Qms: 4.00
Cms (mm/N): 0.19
Vas (L): 12.0
Mms (g): 87.7
Mmd (g): 85.9
Rms (kg/s): 5.4
Airload (g): 1.8
No (%): 0.13
SPL (dB - 1W/1M): 83.5
BL (T*M): 12.4
*Xmax10 (mm): 7.6
Sd (cm2): 211
EBP: 73.58
Krm (mOhms): 0.30
Voice Coil Diameter: 2.0 51.56 inches | mm
Erm: 1.32
Voice Coil Height: 0.96 24.4 inches | mm
Kxm (mH): 27.6
Voice Coil Layers: 4 layers
Exm: 0.77
Magnetic Gap Height: 0.39 9.9 inches | mm
Rem (Ohms): 30.95
Linear Excursion, (Xmax): 0.29 7.2 inches | mm
Maximum Excursion (mech), pk-pk: 1.80 45.7 inches | mm
Magnet Weight: 38 1.06 oz. | kg
Woofer Displacement: 1.5 0.053 liters | cubic ft.
Net Weight: 3.91 1.8 lbs. | kg
Power Rating: 200 400 RMS | Peak


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## Oscar (Jun 20, 2010)

Brute71 said:


> .... w/ 2 .068m dia vents that are .101m long


You'll never get those size ports installed inside of a 1.5 ft³ box. Double check what you are doing.


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## Nismomac (Jan 3, 2013)

Oscar said:


> You'll never get those size ports installed inside of a 1.5 ft³ box. Double check what you are doing.


Why?
.101m=10.1cm= approx 4 inches long


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## BP1Fanatic (Jan 10, 2010)

So what happened to this build?


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## Brute71 (Jun 6, 2012)

Wound up being shoved onto the back burner :S have way too many more important projects to do so who knows when ill get back to this one :/


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## goodstuff (Jan 9, 2008)

Freeair?


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## Brute71 (Jun 6, 2012)

nope, mostly non-audio related things right now


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