I have been doing this for a while, and with the aid of the XT 32 of the new Denon 4520 and the twin sub (JL Audio F113) and Hsu MBM MK II, things have got better.
But there is no substitute for measuring the bass response.
I have posted before about the dip in response in my sitting position, which ranged roughly from 60-120 Hz.
But unless one measures it more definitively, it's hard to correct. You
could hire someone, or ask for help, but sometimes friends aren't free,
so you just have to find a way. I tried going the PC way, but it proved
too complicated for a PC idiot like myself, so I sat down with my sine
wave CD, and my SPL meter, a pen and paper.
I set the volume to be around 80db, playing through all 11 channels, and
two subs. Then measured the db level as the CD swept from 10Hz to
300kHz. I manually noted the db level for each 10Hz step in frequency
I found dips in the 30 Hz (-3db), 60 (-4db), and some peaks. So I then
played with the ELF, the trim, the slope on my JL Audio, plus the
individual volume control on each of the two subs, and also the phase
button, to even out these bumps and dips.
I also shifted my Hsu MBM MK II to the left side of my seat for a more
even response and better tactile feel. I had to pull a longer subwoofer
and power cable to do this, but the Hsu isn't too big so it also fitted
as a coffee table, albeit one that shakes - free milkshare anyone?
Some of these controls are not available on your unit, so if you don't know what they are, you don't have it.
The frequency response curve looked better, and I engaged Dynamic EQ,
and found the bass too strong for me, so I backed off on the level for
the two subs combined on the Denon, and it's been a rather satisfying
experience without killing my hearing.
I like to keep my hearing, so conversation levels are around 60-70db, and the explosions are around 80-90db.
When you turn things up as some will, there is lots of headroom, and also that rumble and thump.
Skyfall is a very well engineered disc, and highly recommended as a demo
disc, and you get good surround, and lots of low rumble, plus a few
chest thumping scenes.
The summary is, after the basic Audyssey or other forms of auto-eq and
calibration, you can either employ a pro, or get a SPL meter, and a sine
wave frequency wave disc and measure what your own room sounds like,
and get down to tweaking the frequencies.
Sometimes bass traps, and diffusers etc will be needed, and all this
effort will pay off, when you get the kind of sound you lust after.
I have no financial interest or other interests in any of the items / events I write about.