510, I had a different approach to the responce of the head. I was studying my 22" bass and noticed that it has a 45 degree spoon bit cut on the bearring edges. Now I figured that since the larger air pocket wedge being forced through the smaller Di. drum shell increased the speed of the pressure to the resonant head and met no resistance or back pressure because the other end has the same bearring edge. When you calculated the area of the bass drum shell, did you draw a line at the bottom of the bearring edges and measure just that area, or did you go from end to end useing the outside length ?? I never really thought about the vent hole releaseing pressure !!
OddBall - Thank you! I appreciate your detailed info here about the bearing edges. Your response has the depth I was hoping for!
Some years ago when I was waiting to find a vintage single tension bass drum like a friend of mine had had in his earlier days, I started evaluating the internal drum area size. The older sounds I was favoring were all made on those larger diameter shallow shelled drums. I felt that maybe when the drum builders changed to the new deeper shell that they may have kept the same internal area size as to maintain the same frequency range availability (still not sure). My calculations were just based on the advertised sizes as I had yet to acquire even my first bass drum, not hands on, and as considerate of those fine details as your response.
As I’ve said earlier in this thread, I had been reading posts that seemed to indicate a perception that a shallower shelled bass drum seemed to “speak quicker” than a deeper shell. I thought that that could truly be the case (less distance between batter and resonant head), but realized that the vent hole or other holes would likely be the reason for a deeper shell not to respond the same (If you remove the holes no air can escape and the resonant head moves more exactly in response to the batter etc.). Now keep in mind I only presented my vent hole thoughts in this thread. As to try and avoid a “long winded” post, I am viewing this subject from a, “all other things being the same” perspective. I know, as most of us do, that other physical principles apply for other parts of the drum anatomy and are important. This thread is to explore what potential an adjustable vent hole could have to control the “speak” of the BD (low frequencies are very wide and travel slow so faster response might be noticed more with BDs than other drums) .
So for those who are interested, can we get a smaller diameter deep shelled BD to “speak” like the larger diameter shallow shelled BDs by using an adjustable vent (maybe much larger than traditional vents)? then strategically placing it to possibly eliminate the need to cut a hole in a resonant head etc.?