Ha! Funny you should post this, I am listening to tunes in my office on an old Bose Accoustimass(?) system I picked up for free as I type, and streaming music over to my old receiver via a bluetooth-to-RCA receiver similar to this:
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Been doing this for at least 6 years; my specific model is no longer made.
Also stream Video and Calls from my laptop in the office (or obviously any other BT source).
If you want to go hi-fi, there is this (but IMO unless you have a good source AND good system, no need):
These little Bose systems are great for movies, and fantastic for being covert, clear, and loud. And you cannot beat FREE!