Question: Which band along with two other British bands is referred to as the "unholy trinity of British hard rock and heavy metal in the early to mid-seventies" whose performance was featured in a 2011 studio compilation album at the BBC's Maida Vale Studios?
Sentence (from "Live Lounge"): The Live Lounge is a segment on the British radio stations BBC Radio 1 and BBC Radio 1Xtra.
Relevant evidence: No