[GustavMahler]

The specs shows output of 2 x 2.4 mW. What does the first 2 mean? It has only one output and no gain settings, Only volume.
And how can i know how much wattage i'll get with certain headphones with certain impedance? I know how to calculate this only when they give the voltage, Not the wattage.. http://www.usa.philips.com/c-p/SA2VBE08K_17/gogear-vibe-8gb/specifications
Thanks!

 

[RRod]

  The specs shows output of 2 x 2.4 mW. What does the first 2 mean? It has only one output and no gain settings, Only volume.
And how can i know how much wattage i'll get with certain headphones with certain impedance? I know how to calculate this only when they give the voltage, Not the wattage.. http://www.usa.philips.com/c-p/SA2VBE08K_17/gogear-vibe-8gb/specifications
Thanks!

 
2 channels. You can get voltage by power = voltage^2/resistance (pretending impedance is resistance), though without a listing for what impedance that 2.4 mW is delivered at you're missing some info.

 

[GustavMahler]

Do i need to include the amp's impedance or only the headphones? And maybe it's possible that the 2.4mW is delivered at about 0 impedance and that's why they don't list with what impedance? Thanks for the help, You helped me understand many things
Btw, If the cans impedance is 32ohm, Is my calculation correct that the voltage is 0.277V?

 

[RRod]

  Do i need to include the amp's impedance or only the headphones? And maybe it's possible that the 2.4mW is delivered at about 0 impedance and that's why they don't list with what impedance? Thanks for the help, You helped me understand many things
Btw, If the cans impedance is 32ohm, Is my calculation correct that the voltage is 0.277V?

 
Yes on the 0.277V. The impedance you need above is the headphone impedance at which the amp will deliver 2.4mW. Not sure if there is a "default" for this.