"It was rehearsing in the studio, at which point they were setting up the sound, and once we'd got the thing together they'd actually record it, without us knowing sometimes!"

Noel Redding's quote is referring to the process of taping music in a studio. He is describing the procedure of practicing in the studio, which involves setting up the noise and making sure everything is all set to tape-record. As soon as the sound is set up, the musicians would record the tune without them knowing. This means that the artists would not know when the recording was happening, and the recording would be done without any practice session. This procedure permits a more natural noise, as the musicians are not aware of when the recording is occurring and can play the song more naturally. This procedure likewise allows for more spontaneity, as the musicians are not knowledgeable about when the recording is taking place and can play the song more easily. Overall, Noel Redding's quote is describing the procedure of taping music in a studio, and how the musicians are uninformed of when the recording is taking place.