Reversed audio has identical magnitude spectra: the time-frequency resolution tradeoff
techNmak · x · 2026-10-27
A clear explainer of why reversing an audio recording leaves its Fourier magnitude spectrum unchanged (only phases flip), meaning magnitude alone can't tell when frequency components occurred. Covers STFT spectrograms and the fundamental time-frequency resolution tradeoff: short windows localize events but blur nearby frequencies, long windows do the opposite—and zero-padding can't recover lost resolution. Relevant to speech analysis, mechanical vibration, and radar/sonar engineering.
More from Research
- Kevin Bryan: maximizing raw accuracy is rarely the right way to train AI assistants — Afinetheorem · 2026-10-27
- Szegedy: a flaw in common training losses went unnoticed for over a decade — ChrSzegedy · 2026-10-27
- Claude research model claims to refute Exponential Time Hypothesis with 14M-token autonomous run — scaling01 · 2026-10-27
- "ETH is false": CS community buzzing over claim that upends SAT exponential-time assumption — akbirthko · 2026-10-27
- RL environments essay: knowing how to operate software isn't knowing how to achieve goals — ShenRaphael · 2026-10-27
- Δτ-Bench: Agents Face a Moving Tool Frontier, Best Model Scores Just 42.3% — UniversityCollegeLondon · 2026-10-27