Newbie sub question (1 Viewer)

[JohnMM]

Can someone explain this to me in somewhat of layman's terms? (FYI: room=1300cf, subs calibrated w/AVIA).
1) I have an Infinity BU-120 sub. It sounds OK, not as much impact as I would like.
2) I borrowed a Velo CT-120. It sounds better, getting closer to the impact I would like.
3) I'm considering an SVS 20-39. From what I've read, I'm hoping it will give me the impact I would like.
I can appreciate that there are many factors that influence the quality of a sub's output, and I don't want to get into that. I am more interested in how (or not) the following figures from Tom Nousaine correlate to points 1 thru 3 above:
infinity bu-120: 100db/32hz, 90db
velodyne ct-120: 101db/20hz, 87db
svs 20-39cs: 109.5/20hz, 105.8db
To put it another way, how do T Nousaine's figures above correlate to my unscientific findings that the velo has more impact than the infinity; and that the svs will blow them both away?
Thanks...

 

[Tom Vodhanel]

the 20hz output of the 20-39cs was 91dB(105.8 was recorded at 25hz).
remember, that's not maximum output...but max output using a 10% thd limit. THis has little to do with the frequency response of a unit.(TN notes that too...usually nearfield and at the listening position).
Generally, the lower and flatter a subwoofer can play...the more *tactile/impactful* it will seem. Another key issue is the subwoofers ability to maintain it's response signature as the volume levels increase. A subwoofer that might measure flat to 20hz at 90dB...could show a severe rolloff an octvae higher(40hz) when the SPLs are increased to more HT representative levels.
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