In message , The Natural Philosopher
writes

snipped

One decibel is DEFINED as teh smallest difference in sound you can hear
volume wise.

1dB is reckoned to be about the smallest difference you can detect
listening to a pure tone; 3dB is about the smallest difference for
'normal' sounds.

All other things being equal, 43dB will sound noticeably quieter than
52dB.

Cheers
--
Keith Wootten