Is there a variance in the sound of Grados of a particular model? I ask because I keep reading about the 325's being bright, harsh, sibilant...mine are none of these things. Mine are rich and full and not sibilant at all. Is it possible I got an odd pair?
The 325 has some extra sparkle to it, which some describe as overly "bright." I never found mine to be "harsh" except when I wanted more bass and instinctively cranked them up. It's easier to get treble than bass. If you crank up the volume, you'll get more treble and you'll complain that the headphones are "harsh." They're certainly brighter than the 225, which is why 225 lovers love to complain about the 325. But we're talking about unamped headphones. With the felt over the driver backs, you really need a decent amp to get the bass to come out and play. With my M^3 with variable bass boost, I could ratchet up the bass and establish the tonal balance I wanted. In doing so, I'd never have to crank the headphones too loud so they never came across as "harsh."
Of course, tracks vary in their tonal balance and some tracks are sibilant to begin with, just as some tracks come across as muted. Recording environments are not identical, nor are the aesthetic judgments of sound engineers.
I found that when I punched out at least four holes on the driver back, I got as much bass as I was looking for when I cranked up the bass boost on my amp. Punching out these holes made the bass boost unnecessary. In fact, I always seem to end up punching out all ten, with no bloated bass at all. Four may be the polite thing to do but I never heard any problems with punching out all ten, and curiosity always seems to get the best of me in that regard.
When I compare the vented 325 to the 225, the 225 loses luster. A tonally balanced 325 has sparkle the 225 doesn't have (unless you remove the grill cloth, in which case, you get the sparkle without spending the extra $100). A vented 325 is an awesome headphone.
