It's very-likely that some listeners perfer some headphones with the frequency response changes you get with a higher impedance source. But the manufacturers will design, test, and "spec" the headphones with a low impedance source, because with a varying impedance sources the performance will vary.
Its even possible that some headphones improve with a higher impedance. But if that's the case, a high-quality manufacturer would add resistors inside the earcups (and they would still test & specify with a low impedance amplifier).
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Its even possible that some headphones improve with a higher impedance. But if that's the case, a high-quality manufacturer would add resistors inside the earcups (and they would still test & specify with a low impedance amplifier).
QUOTE
I was surprised to learn that the expensive amp HDVD800 have an output impedance of 43 ohms.
Are you sure that's the effective output impedance? (I didn't see the output impedance or output voltage spec on Sennheiser's website.) Maybe it's the recommended minimum headphone (load) impedance. For headphone & power amplifiers, it's more common to see a spec for the load impedance rather than the internal source impedance... If the spec on a headphone amp says 1 Ohm, you wouldn't want someone to think they can connect a 4 or 8 Ohm speaker. I've never seen a source impedance spec for a power amplifier... If they give you the damping factor you can calculate it.QUOTE
Also there's an article that use a weird analogy with pendulums, suggesting that both overdamping and underdamping problems could exist for headphone. But I'm not sure the analogy is appropriate.
The analogy is OK, but the analysis is NOT!QUOTE
Now imagine a huge motor attached to the pendulum. In this case the motor is so big that it hardly feels the pendulums moment at all. The motor will be able to do what ever it wants regardless of whether its near the resonant frequency or not. The large available horsepower of the motor damps the pendulums natural moments.
That's true! QUOTE
An over-damped system (orange) will be slow to respond.
NOT TRUE if the damping is coming from the "huge motor" (or low impedance). It's true if you add a damper or shock absorber, but a more powerful motor will NOT move the penduleum slower! 