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Bio-Hazard
Sep25-05, 06:57 PM
Decibels are the measuring unit for sound energy. The absolute threshold for hearing is arbitrarily defined as zero decibels. Every 10 decibels correspond to a ten-fold increase in sound. Thus, normal conversation (60 dB) is 10,000 time louder than a 20 dB whisper.

I don't understand the math of the 10 fold system.
Could someone go into detail of it for me?

I just don't see how that works.

10 db = 100
20 = 1000
30 = 10000?

i don't understand the system here.

Poncho
Sep25-05, 07:09 PM
It's a log scale


I(db) = 10*log_{10}(\frac{I}{I_0})


For example


10db = 10*log_{10}(10)



30db = 10*log_{10}(1000)




60db = 10*log_{10}(1000000)

Bio-Hazard
Sep25-05, 07:20 PM
I don't understand that log stuff or I think I'd have this understood by now.

==update==
Ah, I understand it a bit better now after doing some math work. Thank you.

simply the 6 part of 60 could signify 6 zeros after the 1, making it 1 million.