It's 3 -- ah, 3:30 -- argh, 4:00 In The Morning And I Need A Strobelight

[dglenn]

(Or: Physics Goes 'Twang')

I should be asleep. I'm not. Go figure. And I'm puzzled.

Pluck an open string, and you get the fundamental frequency of that string (i.e., that combination of length + mass

Comments

[writerjanice]

You really should join the leftbrainluthiers yahoo group (http://launch.groups.yahoo.com/group/leftbrainluthiers/). Things like this get discussed all the time as well as such things as the interactions of the string energy, the neck, and the guitar top and body.

I think you would like it.

Janice (I will actually build a guitar some day...)

[dglenn]

Sounds interesting, if I have time to keep up. I've put in a subscription request.

[blk]

[3] Sorry[9]. Couldn't resist.

Oh no you aren't. :-P

[juuro]

From what I remember of the monochord experiments in the phys.lab. course, there is almost always a traveling-wave component as well, and those do add all kinds of non-harmonic tones to the timbre. Also, in addition to the pretty two-dimensional vibration, the chord has a strong tendency to go into helical or other three-dimensional vibratory modes, and those have slightly different overtone structure from the plain sinewaving.

Have you experimented with flageolet tones?

[dglenn]

This is helpful information (though I still want stroboscopic imaging because this explanation, while making me less confused, makes me even more curious).

I haven't played fipple-flutes into a scope yet. If the audio capture on the machine I've got Audacity installed on is good enough, I'll try that. (Or are you referring to how the sound coming out the foot and the sound coming out the fipple combine at different distances? Or something else entirely?)

[juuro]

In the bowed-string jargon in Finnish (and to some degree, in plucked-strings as well), flageolet tones are ones where you damp the fundamental and force an overtone node by softly touching the string at the desired location. As a result, the string goes into an almost pure overtone vibration mode, with tone quality very different from normal fingering.

[juuro]

I think the concept of "artificial harmonic" referred to elsewhere in the comments to this entry is synonymous, or at least closely related to my flageolet tones.

[blueeowyn]

http://www.stlyrics.com/lyrics/classicdisney/heffalumpsandwoozles.htm has the root as "confusle"

http://www.angelfire.com/movies/disneybroadway/blusteryday.html agrees

I have also seen it with one Z or 2.

[dptwisted]

If I see you at Balticon, remind me that I want you to show me how to slide an artificial harmonic (I'm assuming that's what I'm hearing on Zep's "Black Mountain Side", which confuzzles me how it's done [although it sounds more like a bend than a slide, which really messes with the brainpan]).

[dglenn]

Will do, if I remember. There's really not much to show, just a lot of getting your hands to do it: it's only as complicated as it sounds, and the closest thing to a 'trick' to it is that it helps to be both firm and precise to avoid accidentally muting the harmonic during the slide. Sounding the artificial harmonic in the first place is the hardest part.

Oh, and you can bend an artificial harmonic. Sound the artificial harmonic, and bend the string. :-)