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I was dabbling around on my keyboard and noticed a strange effect that I'd like to learn more about.

I'm sure this is a well-known effect that probably has a name, but it's a little hard to google this purely by its description.

I was playing the second inversion of G, followed by F in root position.

notes showing the two triads

But even though all three "voices" went up (D -> F, G -> A, B -> C), the combined chords sound like they go down.

Here's a recording (one octave lower): chords.mp3

To my ear, it sounds like the most "prominent" notes, the ones that define "up/down" for me (I'm sure there's a word for this) are the B in the first chord and the A in the second chord, and therefore it sounds like it's going down.

Here are the same chords, followed by those two individual notes: chords-and-notes.mp3

I experimented a little more, and I noticed that this effect disappears at the high end of the keyboard. When I play the same thing two octaves higher, the second chord does sound higher than the first, as expected.

Recording: chords-high.mp3

I also noticed that the effect disappears (or at least becomes less pronounced) when I play quieter.

Finally I noticed that this effect also does not happen if I modify the chords (e.g. if I play Fmin or Fsus4 instead of F major, there's clearly an upwards motion).

I tried different instrument samples and it still happens, so it seems it's not a quirk of that particular piano patch.

So my questions:

  • Is this a universal thing, i.e. is everyone hearing this, or is it just me?
  • Why does this happen?
  • Does this effect have a name?
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  • Another observation: Now that I play these recordings back through the squeaky speakers of my phone, the same effect is much less pronounced. So clearly this has something to do with low frequencies.
    – balpha
    Sep 1, 2023 at 10:02
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    I don't hear it, but the psychology of acoustics is known to be surprisingly complicated. A pretty straightforward guess is that your perception is influenced by comparing the logical root of those chords (G to F) rather than the physically lowest note (D to F). Sep 1, 2023 at 10:11
  • @KilianFoth Interesting. It feels like it's more the thirds (B and A) that seem to define it for me, but yeah, that could be it. Still wondering why the lack of low frequencies seems to undo it 🤔
    – balpha
    Sep 1, 2023 at 10:32
  • Two people can hear the same audio but interpret it differently. See this old question: music.stackexchange.com/a/16648/9426 I think when you hear that chord progression you're mentally constructing a bass note which isn't actually there. Other people listening to the same audio won't necessarily hear what you report. Sep 1, 2023 at 11:40
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    I hear the effect you're describing quite strongly, FWIW. (The pitch seems to go down in the first recording, up in the third one.)
    – N. Virgo
    Sep 2, 2023 at 5:17

5 Answers 5

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Notes have an overtone texture, and chords, particularly simple ones imitate that to a certain degree, making them "point" to the root note. This effect is strongest for the fifth (fourth in inversion) and then the major(!) third (meaning the effect you experience will be different when using minor chords or more complex chords).

Organ registers use this trick as Mixture breaks to avoid minuscule pipes that don't really contribute to the tone.

You can experiment with how strong that effect for you is at various octaves by using overtone-rich patches (brass instruments may do) and rather pure patches (ocarina is a good candidate), but you need to avoid patches containing vibrato or other modulations. Just straight tones.

Piano is additionally tricky because of disharmonicity: it has a tendency to have muddy lower chords (grand piano less so than upright) and thin higher chords that indeed retain more of an individual note character than as a blended chord.

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    Indeed, the effect is much more pronounced with a brass instrument than with an ocarina. Thank you!
    – balpha
    Sep 1, 2023 at 13:12
  • @balpha - sounds a bit soft to me. Triads on a brass instrument or ocarina? Come on..!
    – Tim
    Sep 1, 2023 at 17:55
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    @Tim Oh no, of course I picked up my three trumpets and played simultaneous individual notes. I have a big mouth.
    – balpha
    Sep 1, 2023 at 22:20
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    @balpha Is that you, Gunhild?
    – user94421
    Sep 2, 2023 at 8:45
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Probably no official name for this. But it could be that you're hearing V>IV in key C (G>F). This is a common change in any accompaniment, and trying it in different keys - A>G in key D for example would verify the phenomenon to a degree. Particularly if it all ends in a plagal cadence (IV>I).

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  • Yep, I hear it in A>G and C>Bb as well. Any idea why it would be different in different octaves?
    – balpha
    Sep 1, 2023 at 12:30
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I hear this now and then, but not always. I think that we (often) hear the root movement as well as the actual frequency. The frequency of each note rises but the chordal root moves down from G to F .

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  • I tried this on a piano and as written it sounded as written. However, playing the G chord DGB an octave lower and a G6 (BGD) higher at the same time, then raising to 2 F chords (all notes higher), it sounds like the second progression goes lower in pitch. Perhaps this is related to the alternating tritones in several octaves phenomenon or the Shepard tones.
    – ttw
    Sep 2, 2023 at 2:00
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I believe the answer to this question is a combination of the accepted answer by @user94416 and the answer given by @Tim. Both answers have merits and in this case are both responsible for the impression of an downward movement.

The overtones heard on a G chord 2nd inversion have high D’s from both the bass note and the root so there is an effect of a ghost D on top of the voicing.

Most people hear the chord progression of G to F as a descending progression regardless of the top notes or the inversions of the chords.

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You have some good answers already but here is a possible explanation. It is implied by some of the others but not quite stated.

If we assume that the notes are just tuned or close enough for us not to notice then the highest note for which all of the first chord notes are an overtone is the G near the bottom of the bass clef. Your first chord will be the 3rd, 4th, and 5th overtones of that. The waveform of your chord will repeat in the same time as that low G. Now, do the same for the second chord and you will get the F just below that G. The notes of the second chord are the 4th, 5th, and 6th overtones of that low F.

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