Numerosity & Inharmonicity

▼ Details: Numerosity & Inharmonicity
Numerosity & Inharmonicity (inspired by Bogaard, Mesik & Oxenham, 2025)
Reference: Bogaard, Mesik & Oxenham(2025)
This tool is inspired by the experiment of Bogaard et al., (2025) to test the listeners’ ability to hear out voices. It uses additive synthesis and formant filtering to recreate the vocal /u/ timbre. The experiment tests how inharmonicity (jitter) affects your ability to count simultaneous voices (1-5). Each voice follows a pentatonic scale while avoiding note overlaps. The Distinct Timbre condition was added to display the effect of timbral homogenity.

Parameters

Stimuli

▼ Experiment
Note: This section is an approximation for illustration. It is not the original experimental setup described in the reference but serves to provide a feel for the psychoacoustic effects at play.
▼ How to

    Start a session and rate the number of melodies you percieve.

  1. Press "Start" to start a experiment demonstration with the selected playback mode.
    2. Mode:
    • Distinct Timbre: The melodies are played by heterogenous timbres.
    • 00% Jitter: The melodies are played by homogenous timbres.
    • 10% Jitter: The melodies are played by homogenous timbres. The harmonics of the tones are jittered by 10%.
    • 30% Jitter: The melodies are played by homogenous timbres. The harmonics of the tones are jittered by 30%.
  2. The demonstration starts at a randomly selected number of melodies present in the mixture.
  3. For each stimulus, judge whether the number of melodies.
  4. A total of 5 stimuli are presented throughout the demonstration.
Select a jitter level to start the experiment.