db volume scaling

[Tim Blechmann]

>> the threshold of loudness perception is about 1 dB, i.e. two sounds with
>> a volume difference of less than 1dB are usually perceived a equally
>> loud (i don't have any reference on that, but my ears confirmed it,
>> after my acoustics professor claimed that in his class). increasing the
>> volume by 10dB perceptually doubles the perceived volume.
> 
> The German magazine "c't" switched from measuring loudness in sone instead of 
> dB(A) some (long) time ago, because that one is better fitted for the human 
> ear:
> 2 sone are twice as loud than 1 sone. 10 sone twice as loud than 5 sone etc. 
> This is not the case with dB (see [1] - blue table at the bottom for some 
> comparisons). 

if you check the table, you can see, that the different examples are
scaled logarithmically, the dynamic range of the human ear from
`breathing in 30 cm distance' to `loud conversation, 1 m distance'
covers a range of 70dB, which is a factor of 1600 from 0.01 to 16 sone.
btw, [1] describes quite nicely, why a logarithmic scale is used in
audio engineering ...

best, tim

[1] http://www.phys.unsw.edu.au/jw/dB.html#log

-- 
tim at klingt.org
http://tim.klingt.org

Im übrigen ist es gescheiter, sich warm zuzudecken als sich zu
betrinken.
  Werner Schwab


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 197 bytes
Desc: OpenPGP digital signature
URL: <http://mail.kde.org/pipermail/amarok/attachments/20090610/cc11e8c9/attachment.sig>