I thought open tuning was about how a guitar is tuned, not drums.
"Open tunings” are when the unfretted or
open strings of the guitar are tuned in such a way as to sound a specific chord."
Open Tunings on Guitar: The Complete Guide By Andy Aledort One of the beautiful things about the design of the guitar is that by simply twisting the tuning pegs one way or another, the world of open and alternate tunings is available for guitarists to explore and exploit. In this guide to open...
www.positivegrid.com
Maybe open tuning on drums is to specific notes or intervals?