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by mbell 4443 days ago
> What does a 18khz square wave look like wher recorded and reproduced in 44.1 kHz.

It looks like an 18khz sine wave, possibly with slightly reduced amplitude depending on the anti-aliasing filter rolloff and fc, but not enough to be audible (18khz isn't audible for a large portion of the population anyway).

> How is phase affecte?.

Probably delayed a bit by the anti-aliasing filter.

> Phase of an audio signal reaching the ears helps you perceive distance and position.

Not at 18khz, the wavelength is too short for your ears to notice any realistic group delay. High frequency localization is most done by ILD and effects caused by ear shape.

> What is the quantization error difference between 16 and 24.

Quantization error in a DAC just defines the noise floor. 16 and 24bit DACs are usually within a few dB of each other in dynamic range, it's really not audible.

> And if the author can't hear the difference between 4bit audio and 12bit audio I question what he/she is listening on. The aliasing would be HUGE.

What does aliasing have to do with bit depth?

1 comments

http://www.eirec.com/DPimages/digisqwvtest.jpg Here is an example of higher sampling rates being useful INSIDE the human hearing range. This example shows transient response. Frequency response and dynamic range are low hanging fruit in high res audio debates. To argue that you can't hear it is a mute point when accuracy is the point, this is a reference quality format. Temporal resolution is the next area to persue if accuracy is of concern. If file size is of concern then high res is not aplicable. What is everyone arguing here? That if they any hear it on their setup it is of no use?