Impedance in headphones vs. speakers - confused


I would really appreciate it if someone could explain the difference between impedance in headphones compared to speakers? I'm confused from the research I've done since it looks like the higher the impedance in speakers (such as 8 ohms) the easier they are to drive. Whereas it looks like the opposite in headphones. A 32 ohm pair of headphones (such as most headphones used for iPods) is easier to drive than say a 600 ohm pair which usually requires a headphone amp. Is that right?
nadman12
Theres's only one thing that I still don't understand. Why is it that an iPod or iPhone won't get stressed out delivering the current required for 32 ohm headphones (apple earbud's or a pair of Grado's for example) but my $3000 integrated amplifier which requires a minimum of 50 ohms has a problem with it? Yet the integrated amp can apparently supply enough current to power 4 ohm home speakers with no problem.

The electronics for the integrated amp to drive 4 Ohm speakers should be totally different & separate from the electronics that is the headamp. There should be 2 separate circuit boards for these 2 separate functions. The electronics that is driving your 4 Ohm loudspeaker is NOT the circuit driving your headphone. Once you have switched off your int. amp & let is sit for several hours to let the power supply caps discharge, pop open the top lid & take a look inside. You should see a separate circuit board for the headamp.
All the money was spent in making a much better int amp to drive a loudspeaker than a headamp to drive headphones. The headamp was thrown in there as a feature with minimal cost & effort. People who are serious about headphone listening more often than not have a dedicated/separate headphone amp.
Nadman12

Power delivered to headphones P=U^2/R, therefore in order to keep the same power/loudness, with higher impedance headphones, output voltage has to be also higher. Loudness becomes limited either by gain that is too low (tailored for common lower impedance earphones) or supply voltage (that is low in battery operated devices) - whatever occurs first.

Same exists for the speakers but in order to deliver more power (especially with SS amps) speakers are low impedance hence amp has to be able to deliver more current (since power is also P=I^2*R) and sometimes reaches amp's current limit.