I did a little experiment in case you do want to use a USB stick for your music. That said, if you have a good way to transfer your music to your phone, streaming your phone via Bluetooth is an excellent way to listen to your music. iTunes should be able to rip your CDs for you -- here's a quick "how to" in order to at least do the conversion from the CD to your computer:
https://www.lifewire.com/how-to-copy-a-music-cd-to-itunes-2438865
I'm not an Android user, so you might have to Google around a little to get the music onto your phone from that point (on Mac, iTunes does that when you sync your phone to iTunes).
Back to USB, in order for the Santa Cruz to play USB music, it appears that the music file type needs to be .mp3 (selectable in iTunes when you rip the CD). There may be other file types, but I know for sure that my music that was file type .m4a does not work on the Santa Cruz. Then, simply copy the directories and MP3s that iTunes creates onto the USB stick (hint -- you can right-click a song in iTunes and find information about the directory that song is in). Here's the sample directory that I constructed:
To start playing music, plug in the USB stick into the left USB port in the Santa Cruz, press the Media button on the dashboard, and select USB Music:
The Santa Cruz will probably just start playing something, and it will look something like this:
A really useful button is in the upper-right corner, called "List" -- that will show you more information about the directory on your USB stick. You can choose songs or artists, etc. by clicking on the left side.
Hope this helps a little bit in some way!
Realistically, it should easily be in the thousands or tens of thousands of songs at least.
