Speech rate can be adjusted independently of pitch through time shifting

Evidence

If pitch can be adjusted without changing the rate of speaking, then clearly the rate of speaking can be adjusted without changing pitch. This is called time shifting; it is often used for fitting commercials exactly into a 30- or 60-second spot. — Eric J. Heller, Why You Hear What You Hear- An…, 1725

Categorization

• DEFINE: Defines time shifting as independent speech-rate adjustment used to fit commercials into fixed-length spots.