Sorry, I have read all audio-related wikis and forum topics, but I am still not 100% clear on an answer.
Connectivity is
VeroV (HDMI) → TV (HDMI) → stereo receiver (S/PIDF max 24/96)
When I set kodi channel setting to 2.0, disable all dd/dts passthrough, and then play truehd/dts-hd, will kodi output LPCM using higher quality audio stream or lesser lossy stream?
I.e what settings give the best quality downmixed 2.0 LPCM output?
Channels set to “2” and no passthrough is the only option if your TV and AVR only support stereo input/passthrough of LPCM. If your TV supports bitstream passthrough of AC3, and your AVR supports AC3, then you might find a preference for letting your AVR do the conversion of that (or not, try it and trust your ears). If your TV allows passthrough of DTS (support for this is very hit or miss among displays) and your AVR supports DTS then setting passthrough of DTS core might provide superior results (but again, just try it and trust your ears).
Thanks @darwindesign
I think I understood those concepts.
My TV supports passthrough of all audio codecs, but my stereo receiver only understands 2.0 LPCM.
So I would prefer kodi to decode and downmix to 2.0 LPCM (including centre channel volume boost), and then TV just has to passthrough LPCM stream as-is.
What I am unclear on is if kodi uses/keeps higher quality audio stream for downmix, or is it always equivalent to ‘lossy’ bitrate?
I’m not exactly sure the details of how ffmpeg does the conversion but you might have some better luck searching the interwebs for that rather than Kodi.
At the end of the day your going to be limited to that toslink connection so max quality is going to be what you get with a quality DTS track.
okay, fair enough. Seems like my kodi settings are correct, and whatever it does in the backend cannot be influenced any differently. So best just leave it at that and enjoy the movies! 