Rear-panel AUX input – XLR and 1/4-inch/6.3mm. Line-level output allows connection to another amplifier with 100V and 70V constant-voltage speaker outputs and 4-16 ohm constant-resistance speaker output. Commercial-grade toroidal transformers produce high performance audio on a wide range of frequencies with minimal noise and high fidelity, even at high volume. Intelligent limiter can reduce excess signal. Reliable protection against overload, short circuit and power fluctuation for optimum reliability. Oversized heat sinks and fan protect against overheating, protecting the amplifier’s working life.