The trombone upstairs

Text 1: Flat 9, by Marcus Tellwright

An original short story extract.

At ten past eleven the ceiling began to hum. I put down my toast and listened. Somewhere above me, in Flat 9, Mr Petrakis had taken out his trombone again. The first note was low and long, a foghorn that rattled the spoons in the drying rack. Then came a run of scales that climbed the walls like something trying to escape. My lampshade trembled. A picture of my aunt slid a centimetre to the left. I banged on the radiator pipe with a wooden spoon, three sharp knocks, our agreed signal, and for a moment there was silence. Then he played the scales again, louder, as if my knocking had been applause. I lay on the sofa with a cushion pressed over each ear and counted the cracks in the plaster, waiting for him to run out of breath.

Give three words or phrases that show how loud the music from the flat upstairs is.