Lack of bass in NHT 3.3.

For grins I ran the same test in my listening room which seems to have the same level of ambient noise and got slightly superior results. About what I expected, my martin logan sub is putting out a little bit more spl than the built in nht subs. Are the nhts defective for putting out low spls and if so what is the cause. If they are running as designed , then do I conclude the would be buyers 17 year old memory is defective. Any current 3.3 pwners out there that can weigh in? Thanks, LS

I’m a 2.9 owner. The mid bass coupler and the subwoofer are room dependent. You have to have the speakers at least 7 feet apart with no furniture too close to the side firing subs.They also need to be close to the back wall and about 22" from side walls which I have mine and they sound good. If you have a TV between the speakers or furniture blocking the side firing subs the woofers are not loading properly and you might be getting cancellation of bass frequencies. Push the TV as close to the wall as possible so it don’t create a 2nd wall near the front of the speaker baffles or side subs. Get a CD that has lots of bass and play the music loud for days. Your woofers both the subs and bass coupler might not be broken in all of the way. The two pairs of connectors on the back try connecting the wires to the bottom set which is direct to the subs first in the circuit. Might be a phase problem. Make sure both the top and bottom connectors are tight, even the ones that have no wires attached to them. Try bi-wiring too. Not bi-amping but bi-wiring. Make sure the wiring is not out of phase. Check to make sure someone didn't wire the woofers out of phase to compensate for a center channel speaker not meant for these speakers. These speakers need to be tuned to your room and system like a fine instrument.

Also be sure to replace the deteriorated foam strip on the front baffle if it's rotted out. It plays an important part of the sound. 

you probably have a room null under 100hz somewhere. i have one at 45 and 75hz. every room is different, you will need to change your listening position or move the speakers. which is why ones that have strict placements are so troublesome.

There butt old but worth the effort. 
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