Sometimes, singing in tight vocal harmony, certain chords locked just right will produce a hair-raising effect: the air buzzes, the sound gets "fuller," goosebumps, psychosomatic tears. I think it comes from overtone overlaps? Sharing rabbit hole and questions so far:
Conversation
Unfortunately, it's hard to convey this effect with a recording—it's much stronger if you're producing it. So I guess I'm mostly talking to other vocalists.
The first key bit seems to be that voices can sing in just intonation, i.e. whole number ratios:
2
10
(I'm totally skipping explanation of overtones, temperament, and the harmonic series here… for a wonderful intro, see 's youtube.com/watch?v=i_0DXx)
1
8
In four-part harmony, singing the harmonic series 1, 3, 4, 5 can produce one form of this effect: i.e. the tonic, and its major triad in second inversion an above.
e.g. this (remarkable) cadence resolves to that disposition in A major (A E A C#): youtu.be/Qo_N9_ZFBhs?t= Tingly!
1
8
I think it feels tingly because of all the overtone interactions between those whole numbers. The bass's overtones reinforce all the other fundamentals; then there'll be strong overlaps at 12, 15, 20, etc.
1
5
In my experience, this effect is much stronger when singing with less vibrato and quite a bright timbre (i.e. more upper overtones!). I hadn't really understood this—I sing mostly contemporary pop—but barbershop stylistic choices are mostly in pursuit of this effect.
2
9
They lean heavily on dominant sevenths, which (tuned in just temperament) are the 4, 5, 6, and 7th harmonics of a root two octaves down. en.wikipedia.org/wiki/Harmonic_ Lots of interesting overtone interactions create an angelic "fifth voice" singing high above! "Ringing chords".
1
5
How do inversions/dispositions influence the effect?
eg If the Notre Dame cadence resolved to root triad instead of second inv above bass: 1, 2, 5/2, 3 instead of 1, 3, 4, 5. That'd emphasize a root-fifth interaction, which might detract from the sus resolution of the third.
1
3
I experience something like this effect with close dissonant chords, too, which barbershop eschews. What's going on there?
e.g. in Eric Whitacre's music, there are lots of so-called "fist chords". These sometimes produce the effect for me too! Why? Overtones aren't very aligned.
Replying to
Why is this effect so much stronger for the singer than for the listener?
There's something in being the *causer*, but it's also physical: when the effect occurs, It feels like my voice, my chest, the air in my lungs, my muscles, all resonate with the room and the other singers.
1
13
Why is this physical sensation so powerful?
It feels almost overwhelming sometimes! Like being given over to a "higher power" for a moment. It's beautiful, moving… and a little eerie. Why do we respond this way? Odd!
"Sense and Sensation in Barbershop": jstor.org.sci-hub.se/stable/41700111
1
15
Goofy question I've been noodling with: it's not easy for an amateur to produce this effect—so could one design a simple cybernetic exhibit to give an untrained person the experience of causing this with their voice? I have a few ideas…
4
14
This feels like a dumb question, but: why don't we notice *destructive* interference more in vocal harmony? This figure shows constructive interference in a harmonic seventh chord—but that assumes everyone's in phase! Which… they won't be, right? Do we instinctively auto-align?
6
13
Related, important: vm.tiktok.com/ZM8bkaJ4J/
3
4
Very interesting replies from suggests that the overtones are a red herring, and the "expanded sound" effects actually come from a phenomenon called "combination tones" (lots of back and forth in subtree):
Quote Tweet
Replying to @andy_matuschak
Combination tones. Hindemith wrote about them in "Craft of Musical Composition."
If I sing frequency A while you sing lower frequency B, then the first-order combination tone produced is frequency (A-B).
Perfect 5th reinforces the bottom note, P4th the top (but octaves down).
1
9
A nice instance of the effect: twitter.com/andy_matuschak
I've noticed I can produce the effect alone by singing one part with a vocal recording of the others. It's better when I can find "practice" tracks which have "my" voice missing—I think because sloppy unisons mess it up.
Quote Tweet
35 seconds on that high Ab, and so shimmery. Really hear an illusory fifth voice singing a high Db above the chord in the last few seconds. youtube.com/watch?v=Mmu-t8
2
3
Experiment! I got a multitrack recording which has a mega-shimmery chord voiced as Db4 Ab4 Db5 F5 (ie partials 2-5 of implied Db3). It's tuned in just T, but I repitched each track to equal T… and the overtones are still amazing. So the effect doesn't strictly require just T!
read image description
ALT
3
Replying to
When you started describing this familiar effect I thought of Whitacre immediately, and was glad to see you mention his work. Have experienced it playing instrumental arrangements of his, and as an audience member, though as you noted you feel it more as a member of the ensemble.
1
1
I think there is something to the idea that you feel it more acutely if you are contributing to it, but I also wonder if it's a matter of being amidst the ensemble. If you're lucky enough to sit inside a drum and bugle corps horn arc when they're on, you can really feel it.
1
1
Show replies