So if you blast inaudible ultrasonic frequencies of 100 kilohertz and 101 kilohertz, you get an inaudible 201 kilohertz overtone plus an undertone of 1 kilohertz that is well inside the range of hearing.

FORBES: Magazine Article

Specter said in the hearing Tuesday that the SEC's handling of the Aguirre matter--the agency continued to investigate the allegations and eventually did interview Mack, but only after the matter became publicly known--was poor, at best, and "has the overtone of a possible cover-up" at worst.

FORBES: Congress Takes On SEC