Frequency?

[exchemist]

Violins are typically tuned to perfect fifths, from the A string (440), rather than standard--so 660, rather than 659.

Edit: Unless you're Tony Conrad or you're doing some crazy Gamelan shit or somesuch...

Yes, G, D, A, E, but he's talking about forcing, not about the natural resonance frequency of the strings.

 

[parmalee]

Yes, G, D, A, E, but he's talking about forcing, not about the natural resonance frequency of the strings.

Also, he was discussing the optimal resonant frequency for the particular string. Obviously, a violin is only as well designed as it is... well, well designed; but I'm not sure that they're engineered with that degree of precision--such that the optimal resonant frequency for a particular string, tuned suchly, is precisely 660 hz, 440 hz, etc., and not a few cents higher or lower. Also, obviously, the particular string itself factors here.

But then, maybe they are--in this day and age; certainly not possible a few hundred years ago though, right?

Anyways, re: under force. I came across an interesting discussion--with lots of links to abstracts with maths way beyond my comprehension--on designing spring reverbs, with the spring under torsion here: https://www.diystompboxes.com/smfforum/index.php?topic=120207.40

 

[parmalee]

And I am saying it can. For example, let's say you drive the violin string with a driver (a voice coil.) Violin strings want to produce frequencies at their resonances - specifically 659, 440, 293 and 196Hz. These are the most efficient frequencies for them to generate, and if you hit those strings with white noise stimulus (i.e. a bow) then that is the frequency they will generate most easily (with nothing else touching the strings, of course.) So if you use your driver to drive them at those frequencies, you will hear those frequencies very clearly.

But let's say you want to drive the G string at low E (41Hz) and so you use your driver to do that. The string will then vibrate at that frequency; it can do nothing else. You will then hear a low E. It will be nowhere near as loud as the G note you would usually hear, because the string does not "want" to vibrate there - it does not mechanically resonate at those frequencies. In engineering terms the driver is poorly matched to the string.

This is a bit of a digression, but, practically speaking, how feasible is such a device--that would work on violins, for instance. By "feasible," I mean: could such be implemented into a small-ish devise (hand-held) that could be used in actual performance?

The Ebow is electromagnetic string driver which employs a pickup, feedback circuit, and driver coil, and so, obviously, it produces only the frequency at which you are playing (apparently, newer models employ some phasing circuitry which somewhat mute the fundamental, allowing the higher harmonics to be more prominent) and really works only with electric guitar--and instruments with strings of a similar gauge. Bass strings are too heavy--well, for the marketed device; you can produce a big, clunky diy device which works with bass strings, but it'll likely be rather heavy and unwieldy. And, of course, it's useless for violin and viola--unless you use steel guitar or banjo strings.

IOW, what would the non-electromagnetic implementation look like? One that would work for non-metallic strings, that is.

Edit: Not that I'm averse to using steel strings on a viola--a combination of guitar and banjo strings work just fine. A bit weird sounding sure--it's the sound of John Cale's viola on V.U. and Nico; but when Cale switched back, as on Nico's Marble Index and Desertshore, it just felt right.

And, yeah, why use an electric bow on a bowed instrument in the first place? Infinite sustain, that's why--for when your arm falls asleep, or you fall asleep, because you're playing a Morton Feldman piece that lasts anywhere from 12 to 18 hours.

Also, I'm just curious.

 

[parmalee]

Too late for edit window, but please disregard weird speculation in post #22. My brain was kinda on fire or something. Obviously there are far too many factors, some of which are completely beyond our control (i.e., climate), to design an instrument with the goal of achieving optimal tension at a precise frequency for any/all strings, under any/all conditions. For instance, with harmoniums manufactured in India for export to U.S. or Europe, the reeds are typically tuned considerably lower (A to ~432 hz) to account for the markedly different atmospheric conditions between continents.