https://www.its.caltech.edu/~politzer/rims/rims.pdf : I attached the same neck and hardware to four variants of the Deering Goodtime open-back to hear and try to figure out what the wood part of the rim does.
If you don't want to read or even look through the nearly thirty pages, there are sound files of single plucks on page 2 and played samples starting on page 24. But in between, there are the sounds of the wood rims themselves, rims with tensioned heads, and taps on the bridge with them all strung up. I also try hard to explain in words what's going on. The differences get smaller with each step but do survive to the plucks and playing. Some folks might conclude that they're not obviously different from variations you can get from playing technique, swappable hardware, and/or set-up.
A surprise for me was how the thin rim (about 5/16" versus 9/16") manages to hold its own. Its secret: it relies on some different physics.
The abstract physics must be the same for any style banjo, but how it shakes out will depend on what else is there. I chose Goodtimes because they're pretty minimal. Also, I chose particular examples because they're within the range that many people play. Nevertheless, they turned out different enough to have something to chew on.
I didn't realize Goodtime had different rim thickness options. Which model has the thin rim?
I'll say just as an anecdote, in my experience thin-rim openbacks are almost universally better sounding than thick rim. The thick rim with a big flathead ring and resonator works great, but for open back with a lighter ring, it seems like thin is the way to go.
KCJones -- It's hard to say everything in two sentences. On page 4, there's section III, which begins:
III. THE RIMS
In the figures and sound samples, the fours rims are always presented in the same order.
It’s actually by age, oldest first. The first is from a year 2000 Deering Goodtime and has 11
plies of maple. So, it is designated “11 ply.” The second is from an example of the upgraded
Goodtime, i.e., 3-ply maple — and labeled “3 ply.” The third is from the limited edition
2023 “Cherry” Goodtime. It has three plies: cherry - maple - cherry — and labeled simply
“cherry.” These rims are all of the same dimensions. In particular, they are ? 9/16?? thick. The
fourth is fashioned from a 12-ply cherry drum shell (from nordicshells.com/) that is
? 8mm (? 5/16??) thick — and labeled “8mm.” TABLE I lists the labels and descriptions
for convenient reference.
When fully assembled, everything else on the thin-rimmed banjo is genuine Goodtime -- and, to my ear, that's what it sounds like more than anything else. In retirement, it is strung with Joel Hooks' Aquila Nylgut Historic 1892 Sized strings and has a mahogany Goodtime neck, also not available for purchase, but produced with the Goodtime CNC. The accompanying photo is from Four Banjo Necks, and One Pot, its.caltech.edu/~politzer/neck...wood.pdf.
The link above to the Four Necks write-up doesn't work, even though it did at first -- a result of AI machine editing. This one should:
https://www.its.caltech.edu/~politzer/neck-wood/neck-wood.pdf
(pretty close, huh?)
Edited by - davidppp on 09/20/2024 12:22:12
Given the comments of KCJones and David Pulitzer above, I wonder why more thin-rimmed (5/16”) open-backed banjos are not made/played. Is it simply human preference for thicker rims or are there other reasons? I have an Enoch Tradesman (5/16” rim) that sounds plenty loud when compared with two other open backs (9/16” rims). Each has a different head and each is made of different wood, so comparisons are not precise. I consider the light weight of the Tradesman a real plus.
