Hello, I’m brand new on this board but this topic caught my eye. I’ve been bothered by the sound of dull “thunky” sounding gongs too. In fact my favorite clock currently in my collection, an Ansonia “Triumph” sidemirror, has such a “thunky” sound that it just seems a shame because the rest of the clock is quite beautiful. I don’t know what the answer is except that I can tell you that there are MANY factors that determine the tone of a chime rod or coiled gong. Some are culled by direct observation as a lover of clocks and doing a bit of reading. But other factors I’m only aware of as a direct result of being a professional musician in a former life (a bass player). The differences between the tones I can get from my bass just from having different strings is enourmous. The type of metal is a huge factor – but chime rods vary in composition from pure copper to stainless steel. Another factor that influences the perceived tone of a give rod or gong is how it’s affixed to the clock’s case.
Again, I really don’t have too much at this point to contribute. But one of my goals is to gain enough competence on my newly acquired watchmaker’s lathe to start experimenting with a couple of ideas I have to create a superior-sounding set of chime rods. And if I can make any inroads in that department, I’d like to see if I can discover the forumla for a nice-sounding coiled gong.
PS…..one thing I can definitely tell you is that the chiming sounds that are generally perceived as being more pleasing to the ear have a audible quality called sustain. If a guitar string or electric bass string or chime rod is found to be rich in the fundamental frequency and produce 3dB or more of even-order harmonics than odd-order harmonics, and have the ability to remain ringing for a few seconds with not a lot of decay, then the sound is usually described by most people as being very pleasant.