In the early 70s I had a large rock’n’roll PA system the upper mid speakers of which were Bose full-range boxes, far higher quality on their own than the domestic stereo systems of the time, and a friend had a top-of-the-line Ferrograph reel-to-reel tape recorder, also much higher quality than the compact cassette recorders then popular.

A mutual friend had a problem. Her next door neighbour in her apartment block used to practice the piano at full volume from about 9pm until midnight, almost every night. Many residents had complained but the Body Corporate, dominated by non-resident owners, could not decide on any action. The piano, we guessed, was right against the common wall.

So one night we had a sleepover with the tape recorder and sound system. We recorded his practice from 9pm until midnight, and then played some of it back at a slightly louder volume from 2am until about 2:30am, and again from about 4am until 4:15 or so, with the loudspeakers just against the common wall. The reproduction was, by the standards of the day, quite superb.

He didn’t move out, but there was never any late night practice again. We waited a few days before quietly removing the gear in plain cardboard boxes, and there were no repercussions.