Today I measured the frequency response of the W15GTI used as a subwoofer in my center cabinet; a three chambered affair. The outter chambers are each 4 cu ft and house the woofers, one (2235) for center channel and the other (W15GTI) a subwoofer. The center chamber is 2 cu ft and ported to the outter cabinets and the baffleboard. All five ports (three to the exterior and two to the interior chamber) are 4" dia x 9.5" long.

I referenced the readings to a cone volume of 100.0 dBL (decibels linear weighted) at 180 Hz and measured the cone and three ports relative to that frequency and level. The cone was measured at a distance of approximately 0.81" from the dust cap while the ports were mearured at their centers at the opening even with the baffleboard. The contribution of the ports is logrithmetically summed with that from the cone and considers the area of the port relative to the cone. For reference, I've also included the readings taken for the 130A that used to occupy the cabinet.

With all the current talk of the high end cut-off for the woofers, I also took the frequency up to 1.5kHz. When I get some more time, I'll do the 2205 reconed as a 2235 that also occupies the cabinet.



W15GTI

Freq dBL

1500 91.9

1450 93.7

1400 95.6

1300 96.4

1200 98.8

1100 97.9

1000 92.3

950 93.1

900 95.3

850 98.1

800 103.0

750 101.2

700 100.0

650 99.1

600 98.7

550 98.1

500 98.8

450 98.8

400 97.9

350 99.0

300 99.2

250 100.2

200 100.0

180 100.0

160 99.8

140 99.5

120 101.5

100 101.3

90 101.6

80 102.3

70 103.1

60 104.3

50 103.8

45 101.0

40 98.0

35 97.0

30 96.4

25 95.4

20 93.4





130A

Freq dBL

180 100.0

160 100.1

140 99.1

120 99.6

100 98.7

90 98.4

80 97.9

70 97.3

60 92.9

50 89.5

45 86.9

40 84.2

35 83.2

30 82.8

25 82.2

20 81.3