FixItSteve La CerraSteve La Cerra is currently mixing front of house for Blue yster Cult. When mixing a loud band in a small club or theater, time-aligning 6/01/2004 8:00 AM Eastern
Steve “Woody” La Cerra
Steve La Cerra is currently mixing front of house for Blue Öyster Cult.
When mixing a loud band in a small club or theater, time-aligning the main P.A. speakers to the backline can focus your mix's low end. Even modest venues provide drive processors at the mix position that incorporate delay on the main outputs. Measure the distance (in feet) from the backline directly downstage to the P.A. mains' “acoustic center.” Multiply this distance by 0.9 (the speed of sound in air at 70 degrees is just under 1 foot per second), which results in the number of milliseconds of delay to “dial in” on the processor. This small delay — typically ranging from 15 to 30 milliseconds — will hold back the P.A. speakers for sound from the backline to catch up. This helps avoid cancellation of low frequencies due to the instrument amplifiers being acoustically out-of-phase with the P.A.