Hypersonic effect

The hypersonic effect is a term coined to describe a phenomenon reported in a controversial scientific study by Tsutomu Oohashi et al., which supports the idea that although humans cannot consciously hear sounds at frequencies above approximately 20 kHz, the presence or absence of those frequencies has a measurable effect on their psychological reaction. Attempts to independently reproduce these results have so far been unsuccessful.

Numerous other scientific studies have contradicted these results, finding that people who have "good ears" listening to Super Audio CDs and high resolution DVD-Audio recordings on high fidelity systems capable of reproducing sounds up to 30 kHz can't tell the difference between high resolution audio and the normal CD sampling rate of 44.1 kHz.