get a subwoofer for one
even though they are rated for mid 30's Hz, it is rare that a so called full range speaker can come close to what a true subwoofer can do. My Maggies have output in the 36 Hz range and there's no way in H they can come close to a true sub. if you don't have a sub, it will be one of the best things you can add to your system to improve the home theater experience...trust me on this
without a sub, MCACC should have set the 900's to Large, meaning they will get all the bass including the .1 LFE channel. you can manually tweak the 63, 125 and possibly even 250 Hz bands to increase the bass in the Manual Speaker Setup menu IIRC. there's a menu option for manually adjusting the EQ. however, before you try that...your seat just may be sitting a bass null from room positioning. this has been discussed thousands of times, many hundreds of thousands of times in this forum and room dimensions is one of the single-most factors in room bass response. if your seat is in a bass null, no amount of power will significantly change the volume of the freq that has been reduced by standing waves. I recently posted about bass & room response in another thread -
and how you positioned the mic when doing the calibration makes a big difference. read my 2 posts.
play a song with a lot of bass or better, a set of test tones from mid-20 Hz to 60 Hz and walk around the room - you will find bass getting louder & softer as you walk from one end to the other and side to side. that's standing waves at work
if you do have sub, to increase the bass, set your fronts and all surrounds, center to Small in MCACC speaker setup to force the sub to handle the LFE channel and all bass < the bass management crossover point. if your surrounds & center have response in the 60-80 Hz range, then set them to Small and set the crossover to 80 Hz. if they only go to 100 or higher, then you'll have to make a decision to either have them miss a little bass between 80 - 100 or go with 100 HZ for all speakers, you only get one crossover point in Pioneers.
if you've already have a sub and done these things, then look at moving the seat forward or back 6-12 inches, or move the sub or move the speakers to find the point where you perceive higher bass. this is all about room dimensions, listening position and sub/speaker location. no auto EQ system can do it all.
and FYI - in case you don't know this
just because the speaker is capable to a given bass freq, doesn't mean it has a lot of sound at those freq's either. it could produce 32 Hz but be down 20 dB or more from the rest of its output. specing a speaker's freq range without the minus dB output means it could be only a couple dB's lower in volume or a whole lot. KEF claims 32 HZ, +- 3dB which means theoretically, they are quite capable of good output at the low end...providing you are not listening in nulls where you perceive bass the most - say from 45-70 HZ range.
but biamping per se won't do anything to increase the bass in your room. that takes some measurements, experimentation with locating the sub or front Large speakers, where you put the main listening seats, and some tweaking of EQ, you can also try to turn Phase Control off or Standing Wave filter off and see if that makes a difference. I can 100% truthfully tell you that in my room, I can move my head about 6-12" forward and it makes some bass freq's louder and it's NOT subtle
I happen to be sitting in 2 bass dips, that are true nulls based on room dimensions and I've compensated for it as best as I can with external add-on bass equalizers but I have limitations on moving the sub and limitations on moving the theater seating.