Headphone Impedance


Not sure which forum to post this question.....

I understand that getting an external headphone amp / headphone combo would be the best way to go but I'm looking at using headphones late at night for background listening while doing some reading.

Therefore, I would be looking at using the headphones with the built-in headphone amp / connection on the new Linn Akurate Kontrol.

If I use the Linn Majik-I integrated pre-amp as an example, the user manual states the following information:

Output impedance:
Line out -> 300 Ω
Tape out -> 300 Ω
Headphones -> 11 Ω

So does this mean that this pre-amp will work best with low impedance headphones like the Grado headphones (32 ohms)?

What happens if I use higher impedance headphones like the ones offered by Sennheiser or Beyerdynamics? Does it mean that I would need to raise the volume?

Also, does impedance value affect sound quality?
agiaccio
"So does this mean that this pre-amp will work best with low impedance headphones like the Grado headphones (32 ohms)?"

No

"What happens if I use higher impedance headphones like the ones offered by Sennheiser or Beyerdynamics? Does it mean that I would need to raise the volume?"

Yes (some headphone amps don't have enough voltage available)

"Also, does impedance value affect sound quality?"

No.
I would not expect there to be any adverse sonic effects from the higher impedance. In fact it may be somewhat beneficial, just as it is desirable to have the input impedance of a power amp be as high as possible relative to the output impedance of the preamp that drives it (everything else being equal).

You probably would have to set the volume control higher, perhaps by 10db or more. That can be calculated from the specified sensitivities and impedances. If you have specific models in mind I can do the calculation, assuming the specs are available.

BTW, the sensitivity of many of the Grado headphones is indicated at their site as 98db/1mV. I believe that is incorrect, and that they meant to say 98db/1mW (milliwatt, rather than millivolt).

Regards,
-- Al