[FireWire]

Hi,

as I was doing research to assist my uncle buying a new pair of headphone, I read in a related article that the iPod had a frequency response of 20-20 000 Hz. That surprised me as this seems pretty limited. I know most people only hear those frequency anyway, but I'm sure it's worth it to go as low as 8-10 Hz, especially on good external sound system, as the bass can still be "felt" by the body. Not counting people with extended hearing range.

The Apple page doesn't say if the advertised frequency was only applicable to the headphone jack or for the line-out (Dock) as well.

Does anyone have more info on this?

[Spheric Harlot]

20 Hz to 20 kHz is "pretty limited"!?

What are you, a ****ing bat!?

No.

Frequencies don't even become continuous tones until they hit about 15 Hz.

CDs don't actually CONTAIN any frequencies above 22 kHz, and digital artifacting starts as low as 8 kHz (which is the upper limit of what an electric guitar can produce).

A healthy toddler can hear up to 16 kHz, sometimes 18 kHz.

To get an idea of why you're wrong, check out some typical frequencies produced in music:

Interactive Frequency Chart - Independent Recording Network



Also, those "frequency response" numbers are completely worthless:

If a speaker has a "frequency range" of 10 Hz to 20 kHz, that say NOTHING about how its response is spread along that frequency range.

If the speaker has a sharp drop-off below 150 Hz, it can measurably have a "frequency response" all the way down to 10 Hz, but you still won't hear any bass.

Or you can have the opposite, where, say, the Sennheiser CX300 have a wide frequency response, but the bass is so bloated that they're just unbearably boomy.

What you need is either a graph, or AT LEAST something like "Range: 20-20,000 Hz, ±1.5 dB", except it's almost impossible to build headphones like that, at least not for less than four figures.

This would be a comparative graph (here for the line output of two devices, rather than speaker response):



As you can see, the iPhone 3GS has sensational frequency response - it's almost completely linear all the way from 20 Hz to 20 kHz.

And even that says little about actual sound quality, as there is phase response and impulse response to deal with as well - things that deal with precision not over frequency, but over time, which is arguably much more important and difficult to get right.

[tooki]

Originally Posted by FireWire 

as I was doing research to assist my uncle buying a new pair of headphone, I read in a related article that the iPod had a frequency response of 20-20 000 Hz.

First, no headphones can produce that range in truly useful way: you can’t “feel” 8Hz vibrations from headphones, that takes a big subwoofer. And practically no adult male human can hear 20KHz. We’re lucky to hear 18KHz beyond childhood.

(I also seriously doubt that anyone has a truly extended frequency range. What certainly is true is that some people are more attuned to listening to sound itself, but that’s perception, not an actual ability to hear things others can’t.)

Second, 20-20K is the range stated for CDs, which are practically always the source for music on an iPod. (I bet that most iTunes Store tracks were also created from CD.)

In other words, even if the iPod could do more, there’s no practical source of music at any superior quality. (Ripping the 20 DVD Audio and SACD titles in existence is not easy, and AFAIK not even possible on Mac.)

[Spheric Harlot]

Originally Posted by tooki 

In other words, even if the iPod could do more, there’s no practical source of music at any superior quality. (Ripping the 20 DVD Audio and SACD titles in existence is not easy, and AFAIK not even possible on Mac.)

Oh, there's plenty of 24/96 content out there; it's just that nobody buys it on optical media.

(just one example: Linn Records )

Also, there is conclusive evidence that high-frequency sound *is* perceived by humans, though not consciously. Experiments have shown a higher level of brain activity when high-frequency signal is played and lower activity when it is cut.

There's Life Above 20 Kilohertz!
A Survey of Musical Instrument Spectra to 102.4 KHz

[tooki]

I said “no practical source”, and I think that’s a fair statement. And I’d hardly call it “plenty” — the only genres covered are classical and a bit of jazz. Forget about anything else. As someone who listens to neither classical nor jazz, I have zero sources of better-than-CD material.

[Spheric Harlot]

Originally Posted by tooki 

I said “no practical source”, and I think that’s a fair statement. And I’d hardly call it “plenty” — the only genres covered are classical and a bit of jazz. Forget about anything else. As someone who listens to neither classical nor jazz, I have zero sources of better-than-CD material.

For most anything other than classical and jazz, there's little *point* in better-than-CD material. Where there is, you try to get the original vintage vinyl.

[tooki]

I think that’s a very snobbish attitude, though a very common one among audiophiles. The fact is, there are plenty of other styles of music that would equally benefit — like anything with vocals or real instruments. No, Britney wouldn’t benefit much — but a lot of popular music could. (At least if they’d stop mastering everything at nonstop 0db.)

[Spheric Harlot]

Originally Posted by tooki 

I think that’s a very snobbish attitude

No shit now?

(did you miss the smiley, or did the Swiss just completely sponge off what humour you had left? )