Shepard tones are not perceptually identical across the octave.

Evidence

Even with this scheme, some notes are qualitatively different from others: some give a stronger sensation of two pitches; others reveal, with practice, the low frequencies sneaking in to eventually take the place of higher ones when they approach t = 0. — Eric J. Heller, Why You Hear What You Hear- An…, 2120

Categorization

Category: Contrarian or Surprising Claims

• QUESTION: This contradicts the usual claim that Shepard tones are all perceptually equal around the loop — worth checking against cited experiments.

Related

• Shepard tones use only power-of-two partials plus amplitude shaping to create the illusion. (similarity 0.86)
• A Shepard tone creates an endlessly ascending pitch while staying within one octave (similarity 0.84)
• Shepard tones create endlessly rising pitch through shifting autocorrelation peaks (similarity 0.83)
• A sound can rise in pitch forever without ever rising in frequency (similarity 0.81)
• Endlessly accelerating beat rhythms are Shepard tones shifted down in frequency. (similarity 0.81)
• Even nonperiodic noise sounds convey a weak pitch sensation based on spectral energy distribution (similarity 0.78)

Broader Connections

• A Shepard tone creates an endlessly ascending pitch while staying within one octave #corroborates (0.85) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1641