I've never used one so I'm just looking for some feedback on what to look for when purchasing one.
I got this one and has worked well for years. Once you have it, you won't believe you didn't get it sooner.
They come in regular analog (needle and gauge) display and digital display.
They are all the same in use, the digital display takes away the guess work but isn't truly necessary. Needle/gauge is reliable.
Make sure you're using it uniformly around the head (at the same distances away from the tension hoop all the way around the head) and you should be good to go.
Doesn't hurt to re-calibrate it's zero once in a while by testing it on a truly level and flat, hard surface like glass.
Oh and don't let the Drumdial rest for long periods of time with the bottom needle depressed. Rest it on its side.
Drumdial is a brand name, so they're all basically the same save the displays. Find one at the lowest price you can and it will serve you well for a long time.
First, I use a drum dial. Second, just blindly setting a banjo head to an "ideal" setting such as 90, does not help us understand the effects of different head tensions. Ideally, one should use a drum dial interactively with comparative listening. Once a desired sound due to a particular setting has been identified, then subsequent re-adjustments can be made "blindly" using a drum dial.
My point being don't let a tool think for you.
Be sure to read the instructions about zeroing the device. You need to use a surface with no deflection. Apparently some hard surfaces aren't hard enough for this. I use the glass bed on my home copier/scanner.
And let me second what Rob/Banner Blue just said: The purpose of DrumDial is not to help you adjust your banjo head to some predetermined or consensus reading guaranteed to produce desirable banjo tone. The purpose is to provide reliable, repeatable, reference for the head tension that sounds best to you. Of course you can start at 90, 91 or any number that other players have suggested. But use that only as a starting point.
My ability to hear a tap note became inconsistent. I'm happy I bought a DrumDial.
It totally removes the guessing, anxiety and mystery from tensioning heads. I wouldn't be without one.
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