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falkenbd wrote:ok, so we threw the TW-12 in a sealed box that I had laying around (was a box for a 10 but we cut the hole larger).

It was getting exactly 300 watts RMS, the sealed box was probably larger than ideal.

It sounded very good on music, played a 40 hz test tone and stuff was falling off the walls in the garage. Sampled some different music before I left to come home, very pleased with the performance of the sub, especially with the price (thanks to Cargodz for the recommendation)

I can't wait to hear this thing in the ported box that I'm going to be building.

It looks very well built as well, very heavy duty surround, and nice looking cone.

Glad you like it. What size is the box?

i don't have it in front of me, but I think its roughly 1.8 or 1.9 cubic feet.

falkenbd wrote:i don't have it in front of me, but I think its roughly 1.8 or 1.9 cubic feet.

Yeah, thats seems pretty big for a 12" sub. Of course I know nothing about the sub youre using.

according to WinISD this is the response with 1.9 ft^3

Relative
Freq Gain
[Hz] [dB]
20.00 -14.33
25.00 -10.75
30.00 -8.04
35.00 -5.98
40.00 -4.45
45.00 -3.33
50.00 -2.51
55.00 -1.91
60.00 -1.48
65.00 -1.16
70.00 -0.92
75.00 -0.75
80.00 -0.61
85.00 -0.51
90.00 -0.43
95.00 -0.36
100.00 -0.31

So its a little lacking in the low end. The ported box specs are above in this thread.

MobileAudio219 wrote:Glad you like it.

^ Ditto

falkenbd wrote:according to WinISD this is the response with 1.9 ft^3

Relative
Freq Gain
[Hz] [dB]
20.00 -14.33
25.00 -10.75
30.00 -8.04
35.00 -5.98
40.00 -4.45
45.00 -3.33
50.00 -2.51
55.00 -1.91
60.00 -1.48
65.00 -1.16
70.00 -0.92
75.00 -0.75
80.00 -0.61
85.00 -0.51
90.00 -0.43
95.00 -0.36
100.00 -0.31

So its a little lacking in the low end. The ported box specs are above in this thread.

i don't really think that's lacking that looks like standard frequency degradation. remember 98% of music does not drop below 30hz. and only about 80% ever go below 40

you are right, i was pointing out that from this box to a ported box - side by side (in theory and according to winisd) that the low-end of music will benefit from the ported box. you obviously know a lot more about this than I do, so please correct me if I'm wrong.

I'm thinking from 80 hz down this thing will shine in a ported box.

40 z is 6 db different, and 50 hz is 5 db different

proposed ported current sealed
20.00 -17.25 20.00 -14.33
25.00 -9.17 25.00 -10.75
30.00 -2.97 30.00 -8.04
35.00 1.00 35.00 -5.98
40.00 2.59 40.00 -4.45
45.00 2.80 45.00 -3.33
50.00 2.56 50.00 -2.51
55.00 2.24 55.00 -1.91
60.00 1.95 60.00 -1.48
65.00 1.69 65.00 -1.16
70.00 1.48 70.00 -0.92
75.00 1.30 75.00 -0.75
80.00 1.15 80.00 -0.61
85.00 1.02 85.00 -0.51
90.00 0.92 90.00 -0.43
95.00 0.83 95.00 -0.36
100.00 0.75 100.00 -0.31

Bwcad1 wrote:i don't really think that's lacking that looks like standard frequency degradation. remember 98% of music does not drop below 30hz. and only about 80% ever go below 40

Which is why you don't always need a sub sonic filter. If you have a low tuned box (say 30 hz), the sub will pretty stable to down to what, 25ish hz before it starts to unload? How many songs actually go that low... And the sub can actually take the most power at whatever hz the box is tuned to, right?

Correct me if I'm wrong here.

yea plus you start running into impedance issues that low and your power levels will plummet. i think ive used a SSF maybe twice ever. im a firm believe that in a well designed enclosure you dont really need a SSF.

Bwcad1 wrote:yea plus you start running into impedance issues that low and your power levels will plummet. i think ive used a SSF maybe twice ever. im a firm believe that in a well designed enclosure you dont really need a SSF.

So I WAS right, bitchen!