Stroker Pro 15 inch for HT linkwitz transform

[muddasirwaheedmalik]

Hi a pair of new stroker pro 15 inch car subwoofers are available for around 1000 USD. I know its mostly SPL driver but has adjustable voice coil bias overhun/underhung. So it could be tuned/djusted for mimimum SPL and greatest SQ.

There are not much HT subwoofers available here and DIY with a high powered is the only way to go making them sealed and powering them with Pro- amplifiers

SPECS
Fs=26.4 Hz
Qts=0.72
Qes=0.79
Qms=7.8
Xmax=40 mm
Vas=3.6 Cu ft.
sensitivity=86.3 db

Now the manual states both options with vented 3 cu ft, tunned to 36 Hz iwth 2x4inch tubes with 14 inch lenght or SEALED 2.7 cu ft.

Now putting the data in WINISD gives this :Vb=13.7 cu Ft ???? with Fb=30.9 Hz and Qtc=0.795 .... its HUGE but F3= 27.23 Hz.


since its ann HT subwoofer i used Linktwitz Transform with Fo=30.9 Hz, Fp=20 Hz, Qo=0.795 and Qp=0.707. it gives F3=20 Hz now thats cool. with Xmax of 40 mm and 2500 watts power rms.

Now ith 2000 watts applied in simulation the 20 Hz output = 115db!!!!.

Questions
1. Ii cannot check the Excusrion in simulation i dunno why?

2. Any guess why the recommended enclosure volume is 2.7 whereas WinIsd Says 13.7 cu Ft???

3. what the quickest way to implement Linkwitz transform ?

4. Are the 20 Hz 115 db figures reliable ???

[TheBaronGroog]

They can do SQ too, have seen very good reviews on that side

1. Don't use windsd, so can't comment, will model in BBpro for you.

2.The recommended boxes for cars will be too small for the home-cabin gain is a car's LT EQ.

3. LT EQ cirucits can be picked up easily: Linkwitz Transform Subwoofer Equaliser

4. I'll see what bbpro says

[TheBaronGroog]

Cerwin Vega Stroker Pro 15 Subwoofer Review - Subwoofer Reviews - Car Audio and Electronics

If put into optimium sealed bbpro comes up with 3.954cf F3 34.25Hz.
Vented comes up with 11.67cf, F3 13.87Hz, tuned to 15.56Hz.
Won't produce xmax graphs either

I've only ever used LT in my car, where it works very well-my enlcousre is 0.126cf and has an Fb of 76Hz-the sub is played totally below this 60Hz'n'down. For home use I've never tried it, but you'd need the EQ to boost below the F3 at 12dB per octave IIRC.

[muddasirwaheedmalik]

Thanks a lot. i want to use it for HT not car 2.7 cubic feet is recommended by CV for car making accomodation for cabin gain.

what do you recommend ported or sealed ? with tunning to 15.56 Hz i dont think i would be needing LT for ported neither i want to mess wtith diy type LT but i do have a 31 band graphic equalizer with dual band paramerteric equalizer from 20-50 Hz variable, Q=0.7-4.0 boost/cut=+/- 12 db . can it do the job if use for Lt or use behringer FBP 2496.
BTW what would be port dimensions for ported.

best regards

[NEO Dan]

I've been looking - where are the rest of the TSP's for this driver? Looking for SD, LE, BL.

[Zero D]

@ muddasirwaheedmalik

Hi, i put the TSP's into WinISD & came up with this design, based on ...

Int Vol = 10L

fs = 20Hz

Power = 2000W

1 x Port = D = 140mm L = 223mm

trf1.gif

max spl1.gif

x1.gif

@ NEO Dan

I managed to locate the Cerwin Vega Stroker Pro 15 Subwoofer PDF here User Manuals Not exactly straightforward to find they could make the data a LOT easier to find, why they don't ?

I used both HornResponse & WinISD to generate the extra data from the specs in the PDF They correlated quite nicely i'm pleased to say

I inputted Re = 3.6 DCR = Both coils in series

Mmd = 422.10 gm

Mms = 438.2 gm

Sd = 0.0931 m2

Vd = 3.72 L

Cms = 0.0000829 m/N

Rms = 9.32 N/s/m

BL = 18.2 Tm

Le = 1.5 mH

[TheBaronGroog]

The best approach would be to work out how much space you can give to the enclosure and then design the best box for that space. I'd go ported and tuned low, the lower the better for HT and for music-if you tune low you can EQ down the LF for music. Give the space you're willing to sacrifice and I'll give you some designs.

[muddasirwaheedmalik]

vow , thats quite much work you have done. I am a bit surprised about the Bl its a bit low as compared to other similar sized woofers particularly the pro ones.

Any way with 40mm Xmax i think we have quite a room for excursion, at LF. Box size is not issue so i think to avoid thermal and power compresssion at very high levels i would go ported. Again would like to go very very low in tunning , i will be using a pair driven by peavye GPS-2600 amplifier having 900w rms on each channel. So YES big box, PORTED and tuned very low.

SIDE BAR: CAN we add some weight to cone like 440g to reduce Fs by 0.7 factor i.e. Fs=18 Hz , reasons :

1. The sub would be used below 50 Hz only. above 50 Hz i intend to used peavey low rider pro 15 inch driver till 100 Hz.:-)
2. The low end would be extended and i think the motor struture and suspension can take that much extra mass with reduced sensitity we still have 2500 watts thermal power handling capacity to handle the extra power. just a thought

[muddasirwaheedmalik]

Thanks Zero D with 10 L design you have calculated Fs=20 Hz but Baron Groog has said Vented comes up with 11.67cf, F3 13.87Hz, tuned to 15.56Hz.

LETS GO PORTED TUNED LOW. the graph shows reasonable limit within Xmax range. any conseus on design please.

[muddasirwaheedmalik]

looking at the graph above----120 dbs at 20 Hz.......its going to be awesome.