Originally Posted by scannon18
I appreciate the above replies, however things have gotten a bit complicated. What is phase, phase angle, magnitude, etc.? What is "output coupling C?"
Haha every time I think I understand amps it they turn out to be far more complicated than I had imagined.
I am referring to the impedance of the headphone.
Basically phase, phase angle and magnitude are a mathematical way of expressing how much resistance, inductance and capacitance your headphones have with respect to frequency.
In other words, if you see variations in impedance magnitude and phase on an impedance curve then your headphone would have some inductance and capacitance.
To answer the original question: (assuming we are comparing two headphones with a 50 ohm average impedance and the same sensitivity) a headphone with flat impedance curve is easier to drive than a headphone with a "non-flat" (or complex) impedance curve. It doesn't mean that most decent headphone amps won't drive a "non-flat" impedance. One of the many reasons why a solid state headphone amp may have an output impedance of 10 or 20 or more ohms is it is an easy way to make the amp "OK" for driving a complex impedance.
Yes, amps are very complicated creatures.
Lucky for us, headphones are easier to drive than 2, 3 or 4 way loudspeakers or electrostatic loudspeakers, etc.
Impedance: this may drive you to drink, LOL! http://en.wikipedia.org/wiki/Electrical_impedance
something co-written by second year Electrical Engineering student, will require a bit less drinking, LOL! http://www.head-fi.org/a/headphone-impedance
An Output Coupling C is an Output Coupling Capacitor. In an Output Transformerless (OTL) Tube amp it is used to block the DC voltage in the amp from damaging your headphones.
Have you seen the Glossary of terms? http://en.wikipedia.org/wiki/Electrical_impedance written by numerous Head Fi members, more than you really want to know about 'phones and electricity, etc.