Help Figuring Out Decibels: What Is 2% of 90 dB?

Discussion in 'Support' started by threefirefour, Apr 19, 2018.

    1. threefirefour
      Peeping tom

      threefirefour Member Benefactor Hall of Fame

      Location:
      California
      Tinnitus Since:
      5/15/16
      Cause of Tinnitus:
      140dB B R U H moment
      Hey. I have a question that I can't get a good answer to. What is 2% of 90dB? I know dB is a logarithmic scale, so could anyone help me figure this out? Thanks.
       
    2. Bill Bauer
      No Mood

      Bill Bauer Member Hall of Fame

      Tinnitus Since:
      February, 2017
      Cause of Tinnitus:
      Acoustic Trauma
      Are you asking how loud a sound is going to be if it were to be 50 times quieter?

      I might be completely off, but here is my thinking. X db is 10^(x/10). Log base 10 of 0.02 is -1.69897. So 10^(-1.69897) = 10^(x/10). Thus x = -17 db, so 2% of 90dB is 90 - 17 = 73 dB.

      I think the above is right, as 1% = 100 times less power = -20 dB => 70 dB. And doubling power (going from 1% to 2%) is known to mean an increase of 3 dB.
      http://www.animations.physics.unsw.edu.au/jw/dB.htm
      and the first table in https://en.wikipedia.org/wiki/Decibel
       
      • Like Like x 2
      • Informative Informative x 1
    3. AUTHOR
      AUTHOR
      threefirefour
      Peeping tom

      threefirefour Member Benefactor Hall of Fame

      Location:
      California
      Tinnitus Since:
      5/15/16
      Cause of Tinnitus:
      140dB B R U H moment
      Interesting math process. Thanks for the help!
       
      • Like Like x 1
    4. zeroday
      Mellow

      zeroday Member

      Location:
      California
      Tinnitus Since:
      01/1995
      Cause of Tinnitus:
      Driving Truck
      THAT hurt more than my ears ringing...:)
       
      • Funny Funny x 5
Loading...

Share This Page