Marantz AV 20 Home Theater Preamp/Processor with 13.4-Channel Processing, Dolby Atmos, Apple AirPlay 2, Bluetooth, and HEOS Built-in AV 20 represents the highest measure of performance and capability for reference-level home theater systems. This reference 13.4 Channel Balanced AV Preamplifier features Marantz HDAM discrete circuitry, and boasts seven HDMI inputs, each of which is 8K UHD compatible. Product Highlights: Home theater preamp/processor with 13.4-channel processing Supports up to 13