The SA502 amplifier has a 34 dB maximum gain with 2 x 50 watt output. The amp includes three operating modes: stereo, mono or bridged mono as well as three user selectable inputs: balanced stereo (Euroblock), stereo unbalanced mini jack, or high level Euroblock. The SA502 amp has an external 12-32 V trigger, signal detecting auto standby to conserve energy, and dual concentric gain controls for independent channel control. 20 Hz- 20 kHz frequency response. 120 Hz high pass switch. Small size- 1.2" x 3.9" x 4". Rugged aluminum housing.