AudioControl Maestro M9 Preamplifier

The M9 delivers 11-channel processing, sufficient for a 7.1.4 Dolby Atmos system with seven ear-level speakers, a subwoofer, and four height channels with overhead speakers or Atmos "bounce" modules. DTS:X support has been trickling out to different processor and receiver brands over the last few months, with some of the more commercially available names like Denon and Yamaha already implementing it.
As noted, the M9 features seven HDMI 2.0a inputs, all full bandwidth, and three outputs, including two for the main zone and one for Zone 2. All inputs feature optional video processing for upconversion of any input resolution to 4K. The video processing can also be fully bypassed for an untouched video signal pass-through, which is how I ran it during my time with the processor. The back panel also boasts Ethernet connectivity for networked audio sources, RS-232 and IR connectivity for remote control and a USB input for both firmware updates and audio playback from USB media.