I think there have been three proposals as to how M could achieve an object-based audio system with height channels.

1. An updated HD621 (to HDMI 2.x; HDCP2.x) which passes bitstream to a greatly enhanced 861 which does all the processing and provide the additional channels. This would require a major redesign of the 861 to accommodate the extra hardware and maintain it at a workable operating temperature.

2. A greatly enhanced HD621 which does all the processing and provides the hardware for extra channels. This would require a major design of the HD621 and means to coordinate the channels between the two units.

3. A three box solution in which the HD621 is upgraded as in (1), the 861 pretty much stays as it and a third box is added to accommodative the extra channels for those who want them.

Time will tell if any the above comes to fruition. Personally, I’ll be surprised (pleasantly) if it happens in the v9 generation. My Marantz 8802A\861 solution is still working extremely well so I for one am happy to wait.



Main system - Sources (Kodi-HTPC, Vero 4k, FireTV, Sat) into Trinnov Altitude 32 (8-16) (+Roon), Trinnov Amplitude 8 amp & Vivid Audio (Giya G3, V1.5) and REL Stentor III speakers. Others: F80 + Raspberry Pi and other Pi systems.