As a person consistently dealing with lots of tabs (50+) having another tab for solely playing the music is not welcomed. Tab pinning helps, but not much.
I use Chrome's Add to Desktop feature for SoundCloud and other webapps, which adds a shortcut to launch the webpage in a dedicated window (without the browser chrome, etc.) The window is managed separately from your normal browser windows (if any) and acts like a first-class native app.
Nice one, news to me. Ensure "Open as window" is checked for it to open without chrome.