The link below will take you to the Ultimate SPL Chart, an interesting and fun loudness comparison document, so you can assign a number for just how loud it is! When you read it please remember the dB scale is logarithmic, not linear so, for example, 10dB is 100 times the power of 1 dB.  

We think the linked document's fun because:

A. We're silly audio geeks and

B. It's full of interesting facts like these:

-80dB - Underwater nuclear submarine microphones listening to shrimp chewing on food
at 100 meters distance.

15dB - A pin drop from a height of 1 CM at a distance of 1 meter.

117 - 123dB - Home stereo system, very loud and powerful 200 - 20,000 watts (real watts,
not "marketing watts").

135dB - Humans begin to notice a slight "cooling effect" from air expansion.

150dB - Rock concert, "The Who" - two 10 story speaker stacks consisting of 144 double refrigerator sized speakers. Actual peak measured level reached 120dB at a distance of 32 meters for this normalized reading of 150dB. Continuous level reached 114 - 118dB (P) at 32 meters.

215dB - Battleship New Jersey firing all 9 of its sixteen inch guns.

310dB - Krakatau volcano eruption, 1883 AD. Cracked 12 inch thick concrete at 300 miles, eruption heard 3,100 miles away. Sound pressure caused barometers to fluctuate wildly at 100 miles distance indicating levels of at least 170 - 190dB. At 100 miles even shouting in someone's ear could not be heard. Caused fog to appear and disappear instantly at hundreds of miles distance. Rocks were thrown to a height of 34 miles. Dust and debris fell continuously for 10 days after the eruption. Produced very colorful sunsets for 1 year. Ejected approximately 4 cubic miles of earth. Created an anti-node of negative pressure at the exact opposite side of the earth. Sound waves covered 1/10 of the earth's surface. Shock (sound) waves echoed around the earth 36 times and lasted for 1 month.

Ultimate SPL Chart

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