This version here?
The vocals are bassy, but I wouldn't call them muddy. No way is this anywhere close to muddy. I think
congested might be a better term. On the XS they have a similar signature, though the XS has more forward mids so it wasn't as bass-heavy as the M-100 presentation. Through my KSC75, the bass isn't as intrusive and the open sound stage really benefits the song. Blues and Jazz aren't the M-100's strong point. I actually enjoy Buble more on my $15 KSC75. Clarity isn't there, but that openess really draws me into the music.
Damn. I need a better open can now.