An antique vintage wooden metronome set to 42 beats per minute swings slowly back and forth to mark time on top of an old brown piano

metronome music time tempo antique vintage wooden 42bpm bpm beats per minute swing weight back forth second piano old brown rustic prism timekeeping practice rehearsal etude sway oscillate pendulum technology analog click windup pulse device traditional classical metal training composer conductor performance control largo mechanical double weighted clockwork intricate forty two