Thanks for this post. I believe you've basically proved that shell depth doesn't make much difference in the scheme of things.I recently took the time to experiment with two of my kits.
One kit is finished maple with 7x10 and 7x12 toms. Cast hoops.
The other kit is wrapped poplar with 8x10 and 8x12 toms. Flanged hoops.
I put the same type of heads on all 4 of these toms and I tuned them as close as I could to being the same tension.
I had coated single ply heads on the batters and clear single ply heads on the resos.
I set all of the tension rods on the 4 drums to 76 on the drum dial and then I fine tuned by ear.
I was surprised to note that the drums sounded almost the same when I played them side by side.
The main difference was heard only when the drums were hit hard. It was minor!
During medium to light attack I could detect very little difference between the like diameter drums even though there is a 1 inch depth difference and a shell composition difference.
The difference is so minor that if I were to close my eyes and have someone play the drums I would have a hard time telling which drum was hit.
The shallow maple toms are slightly sharper and louder.
The floor toms on these two kits are the same dimensions, (12x14) and I found the same to be true when comparing them.
The maple drum was slightly louder and higher pitched. Not as warm sounding.
Although you don't describe the differences you heard, I would venture that it's shell thickness that's making much more difference than the bearing edges.I have an old Gretsch kit with round bearing edges and shells that are half as thick as my other kits.
If I compare the sound of the 8x12 Gretsch round edge thin shelled tom to the 8x12 sharp bearing edge thick shelled Tama tom, I have apples and oranges.
These two drums do not sound alike at all!
Not even close.
I believe that it is the round bearing edge that is making the most difference.
A great resume. Just about spot on in my experience.These are generalizations.
Diameter mostly affects pitch. Bigger the diameter, lower the pitch.
Depth mostly affects sustain and loudness.
Diameter-to-depth ratio: see above.
Thickness affects the pitch of the sweet spot. The thicker the shells, the higher the pitch they resonate at. Thinner shells resonate at a lower pitch.
Rerings tend to raise the pitch of a shell, so you end up with a thin shelled drum that resonates at a higher pitch than if it had no rerings.
All of these depend a lot on heads and tuning, and shell composition makes a difference, too, so these are only tendencies.
These are generalizations.I have questions for all the drum sound experts:
What do the following variables (in relation to drum shells) do to a drums sound?:
- Diameter-to-depth ratio
- Re-inforcment rings
...I ask myself this question when I notices the vast contrast in timbre between square sized toms of the 80s (a deep, boomy sound) to the more modern shallow fusion toms (a singing sound with a quick attack and mellow set of tones).