I got an Audioengine B1 Multiroom Music Streamer so I could stream Hi Res music through my two channel system. I control it with my smartphone.
B1 Bluetooth Music Receiver | Stream music from your phone, tablet, or computer to any music system or powered speakers.The ultimate Premium Bluetooth music receiver that seamlessly works with all your apps, music, and devices.
audioengine.com
Its about 1/4 of the cost of the very convenient Audality unit Gene dealt with on YT but it seems to perform very well.
I tried Spotify but quickly found out it was not CD quality. I happened to be listening to Beethoven's Ghost and Archduke Violin Sonatas with Jeno Jando and Takako Nishizaki (excellent, BTW), and the quality on Spotify quality was pleasant enough, sweet, but the balance was wrong and not like the CD. I also tried a number of other CDs to see how Spotify did on them. Pleasant but not nearly as good.
I tried Tidal and Quobuz, which did fine on recordings I already had on CD. I have gone with Qobuz, because I found the selections better for some music, not classical (Edith Butler and Angele Arsenault!), but Tidal sounds great, too.