Originally Posted by Andyblues
I will look out for 598.2 568.2 and investigate a HD621.
To use properly (ie discrete multi channel) with a HD621 or G98DP, you need the 568.2mm

The mm board is the multichannel (5.1) input board.

Meridian owner since 1992
Prime & PSU, Focal Elear headphones, Roon (ROCK 8Gi5 NUC), Explorer 1 & 2, F80. 200/203, various Sonos (via Roon).