Does a SACD and DVD-A disk always have a two channel layer ?

[percy]

Or only sometimes ?
When listening in 2-ch mode, other than the 'enveloping' effect that the listener experiences in multichannel audio, is anything else compromised(like quality of the sound itself, resolution, etc.) ?

 

[jheoaustin]

At least DVD-A is not required to have stereo track. For stereo playback, the player can downmix the multichannel track to stereo, or access stereo track if available, but sometimes, you may have to go to disc set-up menu to choose.

 

[sam9]

I have a couple of multichannel SACDs that are only multichannel. If you only have 2 channels, they will still play but all you get is the front L&R.

Wether there is any compromise in the sound depends on the mix decisions during the production not on anything inherent to the format.