You can buy cd quality music or better from HDtracks and other vendors. I tunes is currently 256kb aac, so compressed. Most receivers nowadays would play music from a portable usb hard drive. You can even use a flash drive. I use a 256 gb flash drive, my oppo bdp-95 and tablet media app to remotely navigate the flash drive. Some AVRs may also have media apps that allow that. Other blu ray players can also stream wirelessly, the Sony X-800 or 1000es UHD blu ray players. They use the SongPal app for iOS or android. Here is a description of the SongPal app.
Another option is to buy a airplay capable receiver. That will allow you to select an album or playlist in iTunes and have it wirelessly streamed to your receiver. All denon's have that now, and most others as well.
Or you could buy a music media server. Sony has one. They get pricey though. Almost 2 grand. You cheapest bet would be the 249 sony x-800 blu ray player and it's media app. You can probably navigate an portable attached hard drive to the player. Check the Sony player thread in the blu ray forum and ask there. It says its DLNA capable. Of course if you are upgrading your receiver anyway, just get an airplay capable one and you have no additional outlay. You open iTunes either on your computer, tablet or iPhone select your playlist (my playlists are albums) and it's streamed to your receiver through your wireless network, provided everything is connected to your wireless router.
Depending on your budget you can do this with Oppo. They are shutting down and quitting making players. You can still get the 203 for 549, or look in this forum's classifieds for used 103s if you don't need 4k video disk playback. The Sony is the cheaper solution if all you are doing is music playback and using hdmi connections to a receiver. If you are using any analog RCAs though, you'll need to step up to the Sony 1000es player (2 channel RCAs) or the Oppo (7.1 channel RCAs).
For what it's worth, you still won't find the large catalog of stuff in CD quality to download that exists in CDs. I still buy CDs, rip them to iTunes and load to my phone, or usb drive for playback via my blu ray player.