Drum shell fundamental frequencies test - adding hardware

Headphones / good speakers = essential.  Select HD1080P for best audio.
Further description in the video, but essentially, the more hardware mass you add to a shell, the lower the fundamental frequency of the instrument.  This can be as much as one whole octave when a lot of mass is added.  Not that relevant to the user - more to clear up speculation around this subject.  Shell fundamental frequencies are useful however, when selecting from a large number of shells to make up a set.  Drums don't resonate as individual components, they resonate as a whole.  The more mass you add to a shell, the more input is needed to excite the drum structure, & for that structure to influence the resultant sound.  How the drum builder balances the various design elements dictates the end result.  Individual specifications, in isolation, are close to meaningless.