I'll have to measure the dB on mine! When I'm standing at the lathe (about 6 feet away), I'm guessing it's close to 60. I'll check next time I'm out there.My old compressor is a Stanley Bostitch 6 gallon pancake. I just bought a California Air 8 gallon. Side by side, using a Galaxy Checkmate SPL meter, the old one runs about 93 dB while the new one is about 71 dB. Their advertising claims 60 dB. I'm not surprised that I measure higher than that, but can absolutely live with 70 while ear protection isn't optional at 93.
Releasing the pressure when done is equally loud - enough to grab ear muffs, but that's just cleanup, not something recurring while working.