SoundQubed 2200W Mono Block Amplifier 1 ohm Stable SQ series amplifiers are fully stable down to one ohm. Remote Gain Knob Included. Daisy Chain connection of two amplifiers stable down to 2 ohms Four way protection circuits: Speaker shorts, DC offset, High/Low voltage, Thermal protection Double sided boards with high current MOSFET switching devices 24db/oct slope crossovers, Fully adjustable Low Pass Filter and Subsonic Filter