From what I see in the graph, and this meshes with my experience with wrapping the throat of the bell and using the harmonic bridge, you're not "filtering out overtones", you're just emphasizing the energy output to be more focused on the target frequencies of those overtones. You'll notice that overall, all the overtones are present in both samples at about the same amount, it's just that the red line is more narrow in terms of frequency range around each overtone target frequency, particularly the fundamental.ghmerrill wrote: Tue Feb 10, 2026 8:34 amSo I'm wondering ... Is this really what you want: A kind of "pure" frequency? Are those "waste" frequencies really "waste" -- or are they "added richness" of some sort that is now being filtered out? I don't have an axe to grind here -- just wondering if what you "gain" is really a gain in some appropriate musical sense. Or are you buying an expensive instrument that the designer/maker has worked hard to enrich with certain overtones, and then you slap a damper on it to filter those out? Or is that a totally misguided way to look at it?harrisonreed wrote: Tue Feb 10, 2026 7:37 am This means each overtone is more focused. ... So not only are the "waste" frequencies around the target frequency less emphasized with the plate, the target frequency appears to be either the same amplitude or (in the first few overtones) even more emphasized by several decibels at peak amplitude (where decibels are "worth more").
This to me equates to more projection (less energy wasted on the frequencies surrounding the target frequencies of each overtone, and especially the fundamental, same energy output overall), and possibly a purer sound. Often times a tone with more core and emphasis on the fundamental overtone will be described as "dark". Indeed, wrapping the throat of the bell seems to significantly increase projection, reduce the chances of the tone breaking up at high dynamic levels, and giving a darker sound. But that is only anecdotal evidence from my experience.
Another thing that is not really looked at in this study -- the room. This seems to have been done in a small classroom. If you want to measure projection, etc, half the equation is the room. They should have done it in a large room like a recital hall or concert hall. You can't even begin to talk about projection in a room where the sound is bouncing back into your bell and cancelling itself out. If I have to play in a small room I will actually switch my setup to have less focus and tendency to project, because it's hard to play in a small room with a really focused instrument. That wide warm sound all the college students are after is actually great in a small room, but not so great on a big stage. I know the jury is still out, but being able to tailor your setup to perform better between those two extremes is great.
I don't use the Lefreque but I do have different harmonic pillar adjustments I make for practice rooms vs big halls.
