On Thu, 30 Aug 2007 22:56:28 +0100, "Trimble"
<no-spam@never.spam> wrote:

>My impression is that its down to the final audio output stage...
>The sound quality is the same for listening to mp3 / wma files & the FM
>Tuner
>Recordings made on the unit from the Tuner transferred & played on the PC
>sound OK.

OK, but, unlike a complex integrated amp, these are usually
using only one or two chips, so the "output stage", besides
the possibility of coupling capacitors, is probably straight
from the chip itself. If that chip can't drive low-z loads
(headphones) well, you either use higher impedance
headphones and (probably) suffer some volume loss, or need a
*buffer* stage, a passive voltage gain stage perhaps too if
volume isn't high enough.