Headphone Heights

Posted by reallyralph@hush.com (A) on August 22, 2013 at 07:27:14

Hi all. A therapist recommended a Therapeutic Listening (T.L.) program for a family member which involves purchasing "any old cd player" and a pair of headphones which meet these specs:

Frequency Response: 18 Hz - 30,000 Hz
Nominal Impedance: 150 ohms
Total Harmonic Distortion: less than 0.1%
Semi-Open Air (NOT noise-cancelling)
Circumaural

First thing is, the only headphones I've found so far which do 30KHz are over $150 bucks. Also, the Wikipedia[1] page on CD Audio says "An audio CD can represent frequencies up to 22.05 kHz" so I'm kind of wondering why the headphone specs matter when the audio format doesn't even support the full frequency range.

Second, my suspicion is since most headphones out there sold to kids, students and non-audiophile adults only run up to around 20KHz, "any old cd player" isn't going to have a lot of extras built in to support 30KHz frequencies. How does the frequency response relate to regular old CD player hardware?

You guys know more about this than I do, so just looking for some insight because the numbers aren't all adding up for me. Is there a lot more to all this that I'm just missing?

[1] - http://en.wikipedia.org/wiki/Red_Book_%28CD_standard%29