richard pickworth <richard.pickworth@btopenworld.com> wrotee:
> What is this unit used for and how is it measured?
Look here:
http://www.campanellaacoustics.com/faq.htm
http://hyperphysics.phy-astr.gsu.edu/hbase/sound/phon.html
http://www2.sfu.ca/sonic-studio/handbook/Phon.html
http://www.sengpielaudio.com/Fletcher-MunsonIsNotRobinson-Dadson.pdf
Ask Google for
phons acoustics
and you will find much more.
The "phons" are on the way back - nearly dead.
Cheers
Eberhard Sengpiel
German forum for microphone
recordings and sound studio practice
http://www.sengpielaudio.com