The Solid Drive SD-250 Mini Amplifier from Solid Drive is a 50W per channel (8 ohm) Class D amplifier with maximum gain of 34 dB. Input options include balanced stereo Euroblock, unbalanced line level mini jack, and a stereo speaker level (amplified) Euroblock input for applications with low wattage speaker outputs. The SD-250 has three operating modes: stereo, dual mono, or bridged mono. In stereo, each input channel flows directly to its corresponding output channel. The amplifier has three preset EQ settings for use with a SolidDrive speaker in drywall, glass and wood. It also has a flat setting for unequalized full-range amplification. In dual mono, the left input is fed to both output channels. In bridged mono, the left input is fed to the bridged output (4-8 ohms only). This system includes selectable 12 - 32V external trigger input or auto standby to conserve energy.