SA1521
Mackie's SA1521 is an active 2-way sound reinforcement speaker system designed for extreme accuracy, high output, and smooth dispersion across the entire audio frequency range. It integrates 500 watts of amplifier power, active control electronics, and RCF Precision components into a speaker system with 100 dB sensitivity (1 watt @1 meter). The resulting high resolution and clarity in the critical low-mid and mid-range frequencies are unparalled for a 15" loaded, 2-way speaker system.
Several state of the art advancements in transducer technology have been incorporated in the design of the SA1521. The compression driver uses a new 1.75-inch titanium diaphragm featuring a 3-slot, optimized geometry phase plug. When coupled to the low-distortion, high-output horn, the SA1521 provides uniform power response and correct phase alignment characteristics at the crossover frequency. With the resulting 75°x 65° dispersion pattern,the SA1521 provides very open, natural sound reproduction at extreme output levels.
A 15-inch high-efficiency RCF Precision woofer produces tight, punchy bass. The woofer's magnetic structure delivers an exceptional amount of magnetic force and is responsible for the system's high sensitivity and high efficiency by providing tight control over the cone's movement. This tight control over the woofer's moving mass results in unusually smooth low-frequency response from 50Hz up to the mid-frequency crossover point at 1300Hz.
The amplifier for the compression driver incorporates a Class AB topology, renowned for its clarity, warmth, and high-voltage output to generate extreme SPL levels. A Class G design is used for the low-frequency amplifier, which features two power supplies for improved efficiency and more output power per pound. A signal panel and a power panel are located on the amplifier assembly at the back of the cabinet, separated by a large aluminum heatsink. The signal input panel contains XLR connectors for line-level input and loop-through connections, a level control, and four status LEDs for Power ON, Signal Present, Limit, and Thermal functions. The power switch and IEC AC connector are located on the lower power panel.
The internal processor provides complete system management of all electronic and acoustic functions. These include an electronic active crossover, electronic phase alignment, electronic time correction, electronic equalization, and complete amplifier and component protection.
To ensure long term reliability,the amplifiers are mounted on a massive extruded heatsink, which is convection cooled and dramatically extends the life expectancy of the heat-producing components. The SA1521 cabinet is constructed using both multilayered plywood and pressure injected structural resin. The combination provides a robust enclosure with useful ergonomic features. There are three-part cast aluminum handles on each side of the enclosure placed at the speaker's center of gravity for easy carrying and setup. Handles are also located on the top and bottom of the cabinet for easy movement and relocation. A built-in pole-mount cup is provided on the bottom,and a full-size, oval punched, weather-resistant steel grille protects the front of the cabinet.