papa_hotel_delta wrote: ↑Tue Sep 29, 2020 10:15 am
I don't think physical quantitative analysis ever gets anyone anywhere (or at least very far) when it comes to musical instruments. Mechanical efficiency is never really the point. FWIW the one instrument I've played with a Babicz sounded great, anecdotal I know, but I would give another a try if it was available in some form that didn't require drilling or cutting to install. I guess I'm in the camp of people that is not in love with all aspects of Leo's original design.
Quantitative physics is what has taught those who are interested how electric guitars, acoustic guitars, pianos, wind instruments etc actually work. There are a number of large classic texts on the detailed physics of musical instruments, now including electric guitars eg Zollner's book, now fully translated from German ....
https://www.gitec-forum-eng.de/the-book/
The First Law of Thermodynamics/Law of Conservation of Energy, amongst other universal physical principles, applies everywhere. If a Babicz works well it is because of the principles of vibrating string physics. Which are that if all string vibration frequencies are to be detected by the pickups rather than decay quickly, they must be mostly reflected off the bridge back up the strings - opposite to an acoustic guitar, where vibrations must be transferred through the bridge to the site of amplification, the top plate/cavity, in order to be heard. On electric guitar bridges with more moving/unrestrained parts, string vibrations can excite those parts to vibrate, and so those particular vibration frequencies (mostly higher overtones) are lost from the strings.
But as you imply, physics don't tell the whole story. Psychophysiology (quantitative and qualitative) has helped explain what we actually perceive (ie hear) from musical instruments. Amongst electric guitar scientists, the group at the Sorbonne (Pate and colleagues) has focussed particularly on relating guitarists' perceptions to the electric guitar's physics. For example, it does not follow that a bridge that absorbs the least is necessarily the one that sounds the best. That is subjective.
More strangely, it does not seem to follow that all electric guitar/bridge manufacturers understand the physics that make their products work. So it is not uncommon for manufacturers of "good" electric guitar products to claim their products work well for reasons that are physically non-sensical. But they work well anyway, for other, solid physics-based reasons. Fortunately you can build that stuff without a full understanding how it works (although it helps). Understanding how things work certainly helps guitarist-consumers distinguish legitimate claims from marketing BS though. Reports from within companies suggest that most do product development by simple trial and error, rather than from a full understanding of the underlying physics (save for a few small guitar companies run by engineering PhDs, and several large Japanese guitar/instrument companies that employ the right type of engineers).
HarlowTheFish wrote: ↑Tue Sep 29, 2020 11:01 am
The thing with transferring vibration to/from the body via the hardware is that if you get chunks of wood that are particularly resonant, and you're playing with an amp in the room, you get that cool sustain-into-feedback thing a lot more readily if the body can work as part of that circuit. It also helps those super resonant guitars that shake your ribcage when you're playing actually do that (though it's not necessary -- my Mustang with a Mustang bridge already does that, but sometimes higher-mass/better-contact hardware does that more readily). It's great hardware if your axe is 80% there, but if it's already working well, then it's very much optional.
At high volume in a room, eg at feedback-approaching levels, the
sound waves from the speakers can obviously cause anything in the room to vibrate, to the extent that those things are able to do so. From the strings on up. But the solid guitar body is well down the list of vibrate-able structures, along with the floor. But that's a whole different set of SPL-driven physical conditions to those that operate at normal volume levels, where sound waves are much much lower in magnitude. All measurements of real guitars have shown that solid guitar bodies barely vibrate at all at those more normal sound levels. Because vibrations are not transferred from the strings to the body to any real extent. Necks vibrate somewhat more (extracting vibrations from the strings similarly to bridges, although at lower frequencies). But again, vibrations remain mostly in the strings, otherwise the pickups would not detect them. That doesn't mean we can't sometimes feel the small vibrations in the body and neck, especially at certain low frequencies at which the proprioceptors (physiological sensors) under our skin are most sensitive.
"I just knew I wanted to make a sound that was the complete opposite of a Les Paul, and that’s pretty much a Jaguar." Rowland S. Howard.
