It isn't really *more* bass! but some male voices sound a little lean or something. Brook Benton's voice on Rainy Night in Georgia does not have the same weight I normally hear with other speakers. Also, on the T. Rex song 20th Century Boy, the lead singer's voice is weird.
That seems odd. The inductor I used on the lowpass circuit gives it a full 6dB of baffle step compensation and the frequency response I measured at home and at the seminar was flat down to the bass range. I never noticed any vocals sounding off and I listened to quite a bit of my normal voicing vocal tracks before the seminar.