Advice? Setting up multi-zone audio..



Hi all! First, thanks in advance for any input or assistance.. I'm just looking for some feedback on plans I want to implement this weekend. A little background on the setup.

Dedicated Plex(pass) Server, hosts my complete audio and video libraries
Using Roku's and NVIDIA Shield for A/V streaming
House is fully wired and wireless

This weekend I am adding some simple Polk Atrium outdoor speakers (2 in each location) to both my downstairs patio, and upstairs patio. I was unsure about how to control plex in a TV-less environment, and then I just recently learned about the Chromecast audio. Seems so simple!

For each zone, I plan on using a single Dayton APA102 (~60'ish watts/RMS) to power the Polk's, and use a Chromecast audio as the source. From what I've read, I simply use my smartphone to "cast" to the Chromecast Audio location I want to listen to music. My question is, how much of the "casting" is really run THROUGH my mobile device running the Plex app? Will plex direct play the audio from the server to the chromecast over the network, or is everything routed through my mobile device? If wifi coverage where my mobile device is located becomes spotty, will it affect the playback quality?

I'm just looking for a way to reliably control music output at multiple zones, but do it as "headless" as possible so to speak, meaning no full fledged streaming device, such as a roku and a tv. Am I on the right track? Or are there better options or solutions? I won't say money is no obstacle, but right now, including the small amp and speakers, I'm at less than $200 for a single audio zone, which seems fairly frugal to me.



Okay, so I implemented this today. Works flawlessly, and the casting streams from the Plex server direct to the Chromecast audio, which is awesome!

Setup is:
4 Polk Atrium 4’s (bridged mono)
Dayton AP102 amplifier
Chromecast Audio with 3.5mm to rca adapter

This is outdoor on a 15 x 20 lower patio. Frankly 2 speakers would have been plenty.