Good question, I tried it and set to Stereo, and maxed out my bass to +6, and it filled in the missing lower end.
I sampled songs from different genres:
70's: Heatwave-The Groove Line
R&B:Nicole Scherzinger-Baby Love
HipHop:Gorilla Zoe-Hood Figga
80's:Milli Vanilli-Blame it on the Rain
80's:Lionel Richie, All Night Long
Reggae: Junior Marvin-Just my Imagination
...and a quite bit more.
The music was really bright in stereo, and I noticed my treble setting was turned up all the way from my last speakers, so I quickly brought that down to level 0 which fixed that. I began sampling with and without the sub(Infinity PS-10) throughout the track. I set my subwoofer line level to the halfway mark. I don't like overemphasizing the bass (lower frequencies). I was surprised at the difference, rather no difference. The M22's actually had the same bass output at my sub setting. The infinity isn't bad; it has a quite impressive Darla tap. Every bit of music I threw at it, it handled it with tight bass which I preferred over the Subs. Now when I turned up the sub to 75% on the manual line level. It then became clear, it was the Sub that won. But that is if you like bass. I can recommend the M22's as stand-alone if you have an amp with bass adjustments. Now the only music genre where it failed is hip hop, but everything else it handled beautifully. Hip Hop is were I would bump up the bass more than normal out of personal preference. Movies is the other which a sub would do better.
