Dolby Atmos: does it do anything for two-channel reproduction?

I currently use a USB cable from Wireworld to feed a re-clocker from Acousence which then feeds my MSB Platinum Signature DAC through AES/EBU. The MSB does not have a Atmos decoder. So, if I understand you correctly, I would have to purchase a dedicated decoder, and no longer use my MSB DAC? Which decoder do you use? Does it go directly into your preamp? Thanks.

You would use your current DAC for content that isn't atmos. For atmos content you would need a source (like apple tv, amazon fire tv/stick, x-box for streaming or a BRD player for discs). Then you would need either a HT processor or receiver.
I would only go through the above if you want an atmos immersive audio setup with at least a 5.1.2 speaker layout.

If you only want to listen to atmos in two channel use a headphone setup that is enabled with dolby atmos, much easier and also very nice:

https://www.dolby.com/experience/headphones/

For Atmos enjoyment you need an Atmos decoder.
When it comes to Apple Music, then there is a lot of confusion around it.
For one, using iPad or iPhone and Apple EarPods, you can listen to Atmos through Apple Spatial renderer - this will attempt to recreate spatial effect via 2 speakers only.

To really hear Atmos music from Apple Music as Atmos immersive audio (without Apple Spatial Renderer), you need to use appleTV and connect it to Atmos capable  processor/AVR/soundbar,

For detailed explanation see this article and especially section titled "5 - Apple's "Spatial Audio" Mess"

https://www.pro-tools-expert.com/production-expert-1/why-your-atmos-mix-will-sound-different-on-apple-music

Hi OP - I have a HT set up and that shares the space and some equipment with my 2 channel space.  Atmos via Apple or another streaming service isn’t designed to provide a benefit into a 2 channel set up.  As a previous poster mentions, it does make sense via headphone potentially but not in a 2 channel set up.  

I would only look into Atmos for music if you wanted a HT set up with a speaker configuration and equipment that supports Atmos.

For music listening I prefer my 2 channel set up vs Atmos via my Anthem MRX-1140 HT receiver driving my Atmos speakers.  I find Atmos via my HT set up to be a novelty, some songs can be really immersive but from a sound quality standpoint, 2 channel is far better, your mileage may vary.

Again, to recap - unless you want a HT Atmos set up, receiver / speakers there isn’t a benefit, point to adding a HT Receiver to decode Atmos.  Without the extra speakers, you won’t hear the intended differences from stereo recordings.   

Thank you all for the clarification about Atmos. I will stick with 2-channel, I guess.