Club Velvet spent $40,000 on a new sound system. Dual 18-inch subwoofers per side, flown tops, pristine amplification. Opening night arrived. The DJ dropped the bass. The bass did not drop. It just sort of... vanished.

The dance floor felt like a library. Patrons stood confused, instinctively sensing that something was profoundly wrong without being able to articulate what. The DJ pushed the sub level higher. Still nothing. He pushed it to maximum. The amp clip indicators lit up like Christmas, but the dance floor remained stubbornly bass-free. Meanwhile, against the side walls, the bass was overwhelming.

After two hours of increasing desperation — during which the DJ tried three different USB sticks, blamed Spotify's audio quality, and briefly suspected sabotage — someone called the installer. He arrived, listened for four seconds, and said: "Who wired the right sub?"

The right subwoofer's positive and negative leads were reversed. Both subs were reproducing the same signal, but 180 degrees out of phase. At the center of the room — the dance floor — the two wavefronts met and cancelled, producing a null. Against the walls, where path-length differences broke the cancellation, bass was fine. Transfer function measurement would have shown the classic polarity-inversion dip: -18 dB at 80 Hz right where the crowd stood.

The Moral: Always check polarity before opening night. SonaVyx Transfer Function reveals phase cancellation instantly — a 30-second measurement that saves your $40,000 investment.