Tapco SQ2 manual Introduction, About Dynamic Processing, Compressor/Limiter

Introduction

Thank you for choosing a TAPCO® Squeez™ dynamics processor by Mackie®. The TAPCO product line hails back to the days of TAPCO Corporation, Greg Mackie’s first company. TAPCO revolutionized the audio industry back in 1969 with the very first 6-channel mixer specifically designed for keyboards and rock ‘N’ roll PA.

In essence, TAPCO redefined the price performance ratio and made high-quality professional audio mixers accessible to virtually anyone. Today, TAPCO is reborn with the same ideals and is backed by the world-class engineering and manufacturing horsepower of Mackie. The

TAPCO SQ•2 is the first compressor/limiter/gate processor in the TAPCO TAPCO version of Greg by Mackie® family.

About Dynamic Processing

The human ear has an incredible dynamic range (the difference between the softest and the loudest sounds) and can detect anything from the sound of a butterfly sneeze (0 dB SPL, the threshold of hearing) to the sound of the space shuttle taking off (140 dB SPL, very painful without hearing protection). Audio electronics would like to be able to duplicate this dynamic range, but current technology falls somewhat short.

Audio electronics introduces another limitation to dynamic range: noise. Even the best designed audio circuits produce noise due to the physics of electrons moving through conductors and resistors. It’s called thermal noise, and produces that low level hiss you hear when you turn the volume controls all the way up on a mixer or on your stereo system at home.

An experienced sound engineer knows that the louder the mix, the less perceptible the noise floor, because the louder sounds mask the noise. However, mixing at loud levels brings the signal closer to the point of clipping, where the signal can go no larger. Ideally, you would like to provide 10 to 20 dB of headroom between the nominal operating level and the clipping point, to provide a cushion for transient peaks (bass drum beats and cymbal crashes, for example) to get through without clipping. But then the soft passages may become too quiet and the noise floor becomes a factor. Enter dynamic processing.

The Compressor/Limiter

Wouldn’t it be nice if you could have a hand on the faders and be able to quickly reduce the volume on the bass drum and cymbals every time they approached clipping, then quickly return them to their normal levels? A compressor does exactly that. Set the threshold control to the point where you want the signal to stop getting any louder, and set the ratio control to regulate the amount of attenuation applied to the signal when it goes above the threshold. When the ratio control is turned all the way up, it becomes a limiter and the signal stops getting any louder when it reaches the threshold. The attack and release controls are used to control how fast the compressor kicks in when the signal crosses the threshold and how fast it stops acting on the signal when it drops below the threshold. You can experiment with these controls to get the most natural sound, or simply push in the AUTO button and the SQ•2 automatically adjusts the attack and release according to the dynamics of the signal.

TAPCO van (a.k.a. micro bus)

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