Sizzers said:
A headphone amp is a miniaturised version of your main amp - your main amp drives big speakers, a headphone amp drives very little ones.
Speaker size has nothing to do with it, they can just both drive different loads.
True, but you're not going to pump a 100W amp through your cans are you?
Sizzers said:
Most amps - except perhaps at the very high-end - use a series of step-down resistors to reduce the amps output
It's usually just one resistor and the headphone coil then completes the potential divider circuit, the resistor just drops a proportion of the output voltage.
I wouldn't personally know whether it is one or several but that is what I recall reading somewhere.
Sizzers said:
to provide your cans with a manageable load.
? the cans are the load.
Misphrase perhaps, but again you're not going to wire your cans in to your apeaker terminals are you?
Sizzers said:
So the obvious theory is that a dedicated headphone amp will give a more "pure" sound than one from where the output has been steadily reduced through a series of resisitors.
I must be missing the obvious theory, are you saying the dropper resistor somehow colours or distorts the sound?
Not my "obvious" theory, but others express it elsewhere.
Sizzers said:
Some CDP's - such as my Marantz CD6003 - have their own headphone jack and will drive some cans like Grado's with ease but fail utterly with K's.
They are op-amp based like a Cmoy or RA1, some parallel up op-amp stages to improve the current drive but rarely.
Sizzers said:
However, even running your cans through your main amp is not going to have the same sound signature as the one you have through your main speakers in any case so I don't see the argument.
So you don't agree that amplifiers have a sound signature ?
Of course they do, but whatever cans you use you're not going to have the same sound signature of your main speakers are they?