Can someone explain decibels to me...

[BigToque]

I've got a basic understanding of them, but not a great understanding.

On my amplifier, I can select volumes of -99dB to -10dB.

Why are they negative values? and why is it -99 to -10?

 

[KLin]

WHAT?

 

[BigToque]

Originally posted by: KLin
WHAT?

audio

 

[NikPreviousAcct]

sure

 

[beer]

0 dB is considered, in audio terms, a 'reference' value to be calibrated against. 0 dB = 1. -10 dB is 10% of reference, -20 dB is 1% of reference, etc. etc. Each 10 dB represents an order of magnitude since dB is logarithmic.

However, this will deceive your ear - dB values are logarithmic, but so is your ear's response to audio, if that makes sense. Something that is 0 dB (reference) will not sound 1000 times louder than something at -30 dB.

 

[TheChort]

http://science.howstuffworks.com/question124.htm