I've been poking aroung looking at info on various cabs. I came across specs for the Ampeg SVT-410HE. The "usable low frequency" is quoted as 43 Hz. What exactly does this mean to anyone? My understanding was that it was the lowest frequency the cab was able to reproduce. Now I'm thinking perhaps I'm wrong about that... Wouldn't that be a bit of a problem for a bass cab, since the low E on a 4 string is 41 Hz? What good is a cab that can't handle the lowest note of a standard bass?