I'm looking for a decent-quality portable speaker that will play audio output from my PC, all output, not just from iTunes, for example, which is the chief limitation of my otherwise excellent Bose Soundlink speaker. I want to be able to play music from Spotify, not just iTunes; is Spotify coded in some way to work only on certain, franchised wireless speaker systems?

In researching this, I keep tripping up over the Bluetooth issue. Most wireless speaker systems seem to require Bluetooth at the source, i.e. my desktop PC, but, unlike all modern laptops, iPads, etc., I do not think my PC transmits via Bluetooth, unless there is something I'm supposed to be plugging into my home wireless network to stream audio between the PC and a speaker.

Could somebody demystify all this for me? Many thanks.