The top end is rolled off, and of course the noise floor is much higher
@mulveling That Pioneer is pretty nice- and has bandwidth to 28KHz. It shouldn't sound rolled off! If it does, you might want to look at the heads and see if they are worn. If not too badly worn, they can be lapped, restoring both bandwidth and noise floor.
If the heads have not been degaussed the machine can sound noisy and rolled off as well- at the cost of slowly erasing the high end of your tapes! So degauss the heads if you've not already done so.
If it still sounds rolled off, your tapes aren't up to snuff or the machine might need the electronics refurbished (new filter caps and the like).
Tape is the source of many LPs so LPs shouldn't sound like they have any more bandwidth (although the LP media does- typically to 40KHz).