BEHRINGER PMP500 500-Watt 12-Channel Powered Mixer with Klark Teknik Multi-Fx Processor Compressors Black Ultra-compact 2 x 250-Watt stereo powered mixer Revolutionary Class-D amplifier technology: enormous power, incredible sonic performance and super-light weight Ultra-high quality KLARK TEKNIK FX processor with LCD display, dual-parameters, Tap function and storable user parameter settings Studio-grade compressors with super-easy one-knob functionality and control LED for professional vocal and instrumental sound Revolutionary FBQ Feedback Detection system instantly reveals critical frequencies for easy feedback removal