A sound can rise in pitch forever without ever rising in frequency

Evidence

In figure 3.11, the smaller fork is vibrating faster than the larger fork by factor of exactly 3/2. Using f1 = 200 and f2 = 300, the displacement of the smaller tines reads … Notice that it is perfectly periodic. Its frequency is 100 Hz, lower than either the 200 Hz or the 300 Hz component. The two waves return to their starting phase at the same time after three periods of the 300 Hz wave and two periods of the 200 Hz wave; this time is 0.01 second, corresponding to a frequency of 100 Hz. Here is the first hint of a crucial issue, one that extends to theories of music and hearing. If any single pitch can be associated with this combination, it is certainly 100 Hz, but there is no 100 Hz frequency present at all. One can also easily “hear out,” as it is called, the 200 and 300 Hz “atomic” components as individual sinusoidal pure tones embedded in the “molecular” whole. There is much more evidence to present regarding pitch perception, and we leave this subject for a full discussion in chapter 23. — Eric J. Heller, Why You Hear What You Hear- An…, 323 (#corroborates, via linked claim)

Categorization

• XREF: connects to: A perceived pitch can exist with no partial at its own frequency.; A rising pitch can perceptually loop back to its start.; A combined waveform can produce a perceived pitch absent from its actual frequency components — Eric J. Heller, Why You Hear What You Hear- An…, 323 (+2 more)

Related

• A perceived pitch can exist with no partial at its own frequency. (similarity 0.94)
• A combined waveform can produce a perceived pitch absent from its actual frequency components (similarity 0.88)
• Even nonperiodic noise sounds convey a weak pitch sensation based on spectral energy distribution (similarity 0.88)
• A short pop can still carry a recognizable resonant pitch (similarity 0.87)
• The ear perceives a virtual pitch not physically present in a sound’s components (similarity 0.86)
• Endlessly accelerating beat rhythms are Shepard tones shifted down in frequency. (similarity 0.84)
• Pitch is perceptual while frequency is acoustic, and not all sounds have pitch (similarity 0.84)
• A bell’s perceived pitch is usually absent from its actual partials (similarity 0.84)
• Perceived pitch is set primarily by fundamental frequency. (similarity 0.84)
• A rising pitch can perceptually loop back to its start. (similarity 0.84)
• Perceived pitch persists even when the matching frequency partial is absent (similarity 0.83)
• Helmholtz wrongly assumed every heard pitch requires a physically present partial (similarity 0.83)
• Highest common factor of partials encodes perceived pitch (similarity 0.83)
• Combination tones exist below both source tones and vary in audibility (similarity 0.83)
• Pitch can be perceived even when no partial exists at that frequency (similarity 0.83)

Broader Connections

• A Shepard tone creates an endlessly ascending pitch while staying within one octave #exemplifies (0.95)
• A combined waveform can produce a perceived pitch absent from its actual frequency components #corroborates (0.90) — Eric J. Heller, Why You Hear What You Hear- An…, 323
• Pitch shifting can alter pitch without changing spectral character. #expands (0.80)