Multichannel Downmix Support

[onelivewire]

It's been hard for me to track down an answer for this.

I have a handful of 5.1 and 7.1 mixes that I typically listen to on Plexamp. The native plexamp app has the option to downmix these to stereo when I listen at my computer or in the car. However, Plexamp is incapable of casting this downmix over the chromecast protocol. I usually use the WiiM Home app to play back my music, regardless.

There is some talk/documentation for the Amp/Amp Pro/Ultra supporting multichannel in different capacities. However, I can't find any documentation around how the Mini or Pro handle multichannel.

Does anyone have insight into how this functions?

Thanks in advance from a heavy WiiM user!

 

[Burnside]

If you check the pro and mini firmware pages, there’s no mention of Dolby support, so from that alone I’d take it they don’t.

 

[onelivewire]

I follow your logic, but at the same time, Dolby is a specific multichannel codec and not necessary for multichannel support.

 

[Wiimer]

As far as I know, the Pro and Mini don't support multi-channel signal input. If you want to know more, please send a support ticket.

#Only the Ultra, Amp Ultra and Amp pro can decode Dolby digital 5.1 and play it back in stereo 2ch.

 

[harkpabst]

I follow your logic, but at the same time, Dolby is a specific multichannel codec and not necessary for multichannel support.

And most importantly, Dolby Digital is explicitly the one and only multi-channel format supported by WiiM.

No Dolby Digital Plus, no Dolby Atmos, no DTS:X, no DTS:X Pro, no YouNameIt.

 

[onelivewire]

Sad sad. Some of these records only gave decent dynamic range on the multichannel releases.

 

[s3igell]

And most importantly, Dolby Digital is explicitly the one and only multi-channel format supported by WiiM.

Has it been stated /clarified whether DD support is limited to ARC or also USB/Network Input?? Optical Input are noted as Stereo-only.

And the Amp Ultra has the mysterious "USB Audio Output: Supports up to 8-channel 24-bit/192kHz".

 

[Burnside]

Has it been stated /clarified whether DD support is limited to ARC or also USB/Network Input?? Optical Input are noted as Stereo-only.

And the Amp Ultra has the mysterious "USB Audio Output: Supports up to 8-channel 24-bit/192kHz".

Fine over optical for me on my amp Ultra

 

[dtc]

Some other suggestions, although I am not a Plex user.

Can Plexamp do the downmix and then send it to the Pro using DLNA or can you use the Wiim app to connect to the Plexamp DLNA server with the Plex server doing the downmix?

Since you say it is only a few multi-channel mixes to downmix, can you do the downmix to a file and play that?

 

[s3igell]

The "Specs" on the Amp Ultra Spec page look like they were written by the Marketing Dept (with the Technical Writer locked out of the room).

 

[onelivewire]

Some other suggestions, although I am not a Plex user.

Can Plexamp do the downmix and then send it to the Pro using DLNA or can you use the Wiim app to connect to the Plexamp DLNA server with the Plex server doing the downmix?

Since you say it is only a few multi-channel mixes to downmix, can you do the downmix to a file and play that?

Correct me if I'm wrong, but I believe DLNA is basically a file sharing protocol, so I don't think any sort of transcoding is natively integrated. I used the Plex DLNA indexing feature for some time until Plex received native support via WiiM Home.

If Linkplay casting via Plex was introduced, as has been teased, I think it would fix this issue. Interestingly, even though I can watch movies in 5.1, for audio files Plex on Android TV seems to downmix to stereo, so I can't even hear those mixes properly in my living room.

All of that being said, the main draw for these mixes is the improved dynamic range that seems to accompany them. Maybe I'll hardcode downmixes as you suggested. I guess it's not the end of the world for me to suffer through the original 2.0 releases, though.

 

[dtc]

Correct me if I'm wrong, but I believe DLNA is basically a file sharing protocol, so I don't think any sort of transcoding is natively integrated. I used the Plex DLNA indexing feature for some time until Plex received native support via WiiM Home.

You are correct. Some players can do transcoding and then send the result via DLNA. I do not know if Plexamp does that or not. That is why I suggested checking to see if Plexamp can do he downmix and then send it out via DLNA.

 

[onelivewire]

You are correct. Some players can do transcoding and then send the result via DLNA. I do not know if Plexamp does that or not. That is why I suggested checking to see if Plexamp can do he downmix and then send it out via DLNA.

Gotcha. Yeah I think the DLNA Plex integration is unfortunately more of an afterthought than anything else :/

If I recall, there's a memory leak some people experience when using that eventually eats up all the RAM on the host server. The feature is so sparsely used that the bug has remained unaddressed for 3+ years!