Your BD player will send Multichannel Linear PCM over HDMI (you need to configure it to do so, instead of 'bitsream' HD Audio).

Then HD621 will take this from HDMI, separate from video signals that follow its path, add Meridian magic sauce (dejitter, upsample, apodise) and sends in SPDIF format (coax) to the processor.

As there are 6 channels, there will be 3 cables (SPDIF sends 2 channel per cable, like you use in stereo from CD to DAC). No 6 cables (analog will do this), the good thing here is this all happens in digital, ok?

The 3 cables (SmartLink) are coaxial from HD621, and 'VGA' connector in 568: you need this adapter/cable (buy or made DIY).

Then you need to configure (legacy Meridian software) the 568 so that it knows it has the multichannel board inside, and activate it as an input/source.

And you are ready to enjoy everything now smile

Any other past century processor able to let you enjoy HD Audio? (and so cute btw) wink

Lots of detailed info around here anyway...

Basement: Linn Sneaky DS, 568.2mm, ARS Sonum Gran Filarmonia, Ramallo Allegro.
Living Room: 602, Linn Akurate DSM, Hypex Nc400, B&W 802D.