help identify the subwoofer. 10 inch

[muddasirwaheedmalik]

Hi .

Got couple of these from some importer . These are unbranded, unmarked, !0 inch woofers , with 2.5 inch voice coil , 1 inch big surround , i expect Xmax to be around 10 mm at lease magnet is 2 cm high with a bucking magnet is suppose.The surround is good quality rubber the type of JL audio with i inch thichness its unusual for its size.

I measure FS=35 Hz.Unable to measure Qtc by -3db method always gave error.

Currently in a sample box of 1.0 Cu feet tuned to 33 Hz and active LPF of 80 HZ

Sounds good but a little bit boomy. My plan is to use them in 1.8 cu feet volume enclosure for one woofer tuned to 35 Hz for Music and HT may be then it would smooth the boominess .

At around 150 Watts it gives some audible noise , since its dirt cheap around 15 dollars a piece, Any suggetion of using them in pull push vented arrangement to get better linearlity. BTW i intend to use 8 of them in 4 boxes.

[DrDyna]

I bet it's made by Polk, it looks a lot like this one:

Polk Subwoofer Speaker | eBay

[madtecchy]

Wow look at the size of that rolled surround . It Looks like it only leaves about 5 inches of radiating area . Does this woofer have a very large X max.

Regards Ian

[muddasirwaheedmalik]

Yes . Its polk i saw a small sticker on box written polk. but what model is it?
The measurements i just took.

Fs=37.5 Hz
Qms=5.35
Qes=0.35
Qts=0.33

Vas=0.61 Cu feet. and yes its written RD-1045-1 any comments how to use it ?

[muddasirwaheedmalik]

sorry RD-4045-1

[permo]

Wow, the high excursion, low vas and high FS would make a tapped horn a good option. But four of them would be huge!

I think you could go with four seperate ported enclosures, maybe 3.5 cubic foot a piece, each with 2 woofers with one inverted (push pull, not iso). I suppose a single 6 inch port or a large slot port tuning down to the 30hz range would be good. I have no software available now, so I am just guessing.

[muddasirwaheedmalik]

Not convinced about Vas. i measured it in a box of 0.95 Cuft. Can anyone help finding the T/s parameters online.

[muddasirwaheedmalik]

i am going for 4 boxes. 1.5 cufeet each with dual 3 inch ports . tuned to 33-35 Hz. dont know about Xmax. Will buy more of these to get some damn good bass arrray. Like i said its available for 30 USD per pair brand new in a disposed lot imported by a local guy.

[muddasirwaheedmalik]

The bucking magnet indicates its intended for HT application. Can i use two in pull push configuration magnets back to back and two ports one on front and one on back. The reason for pull push is presumed less port noise. i can use one port at back but it will be too long to be practical.

Still any links for the subwofeer.

[permo]

the push pull alignment lowers distortion. The wouldn't be back to back. You would simply mount one driver inverted and wire it out of phase. that is all.

Two four inch ports I think would be OK. With these high excursion woofers you want as much port volume as you can get and still have a reasonable enclosure design.

I can pump these into winisd tonight and see what I can come up with, I am not a fan of acoustic suspension for home subwoofer use, so I will design a ported configuration in addtion to modeling a few bandpass examples as well. It may work great in a 6th order bandpass design.