That "deep bass resonance" really depends on what kind of HDD you're talking about. Is it a modern 2.5" laptop drive, one of those even tinier 1.8" drives, a full-height 5.25" MFM drive, or one of the old 8" drives from the 80s or earlier?
It's a piezo speaker without a case around it, so yeah it will sound harsh. I guess you mean the sound missing is kind of like that hollow resonance from the casing that you get in a 3,5" drive; a bit like the thock from typing on a recent MacBook Pro keyboard?
That said, it doesn't sound like failure, but I think it's missing the deep bass resonances that a real HDD has.