this site on headphone impedence & matching came via eetimes. its
mainly about product design (and spruiking stuff, its not neutral) but
it might be useful as a reference to the issues of the chosen impedence
of the headphones and the impact on the rockbox in terms of driving
requirements, power drain etc..

-G

http://www.planetanalog.com/showArticle.jhtml?articleID=180201405

-- 
George Michaelson       |  APNIC                 
Email: ggm@apnic.net    |  PO Box 2131 Milton    
Phone: +61 7 3858 3150  |  QLD 4064 Australia    
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