[Galaxy S I9000 General] Lei M:
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High Frequency Sampling:

The ear is more sensitive in some areas than some "experts" with measuring instruments want to tell us. At a 96 kHz sampling rate over 40 kHz bandwidth can be achieved. Now comes the excuse of others, the person hears only up to 20 kHz.

This is only partially true. Although the ear hears (depending on the volume, age, etc.) only sine tones to about 16 kHz true. (20 kHz tones heard only a baby) But man indirectly detected harmonics of a sound that may lie in the frequency range above. That these harmonics are critical, evidenced by the fact that a high frequency sine wave sounds different than a triangle, sawtooth or square wave. The difference lies in the distribution and the level of the harmonic ... Therefore also say high-ender that sometimes vinyl records sound better than CDs. And therefore, devices with extended frequency range such as DVD-Audio (DVD-A), Super Disk (SA-CD), Wide-Range DATs sound (96kHz DAT recorder from Pioneer) or the Legato Link system (developed by Pioneer principle, in which you add additional frequencies above 20kHz included) usually better (smoother, more harmonious) as units with "circumcised frequency response". This can also be explained by means of Fourier series analysis, if one represents signals as a sum of sinusoids. For a steeper rise in the time domain (for example, edge of a rectangular signal), the greater has to be the bandwidth in order to transmit this signal. THAT IS NOT THE (ONLY) THE FREQUENCY DIRECT BUT THE RISE OF THE FLANK A DECISIVE ROLE (FOR NECESSARY BANDWIDTH) PLAYS. With a pulse or an ideal rectangle with infinitely steep increase the bandwidth of the (electrical) transmission channel would have to be infinite to the output or the same pulse to obtain the same rectangle, even if the actual frequency is substantially lower rectangle.

The distribution and the level of this harmonic (multiples of the actual original oscillation) is dependent on the signal, the more "square" and it is steeper the sides, the greater the level of the harmonic. A pure sine wave has no harmonics than one, with these signals will always tested!

A 1kHz triangle or a rectangle has e.g. Harmonics (odd harmonics) at 3, 5, 7, 9, 11kHz, etc., where the level drops, however, continuously. A 1-kHz sawtooth signal would at 2, 3, 4, ... kHz harmonics have (even and odd harmonics). For complex sounds would be a broad spectrum of the case, which goes well until about 20 .. 30kHz.

With a 44.1 kHz sampling rate can indeed be transferred to 20kHz tones, but these are only sine tones, because they have no harmonics. So one does not need not be surprised that CD players always sound so sterile since all frequencies above 8 kHz are only approximately sinusoidal. A 20kHz oscillation is only 2x scanned from the original vibration will then be restored ...

In summary: Direct tones above 20kHz can not perceive the man, but you have to carry with them, you want that recorded, non-sinusoidal signal (music) sounds just as possible as the original.

The greater the frequency range of equipment, the better is generally also their transient response. This can be mathematically shown by means of the Fourier transformation.

Why not infinitely wide? -> Apart from the fact that it is not, it does not make sense, because the harmonics Always take higher order level, so that the transmission (music and speech, at frequencies above 10kHz) from the 4th harmonic or 5 Order hardly worthwhile. That is at a 15 kHz oscillation could stop over 45 .. 60kHz, then what explains these sampling rates. For a 16kHz to 192kHz oscillation can be up to 5 Transmitted harmonic, so what, as far as this theory is sufficient. In general, sufficient for most signals up to 10 harmonics, so that the differences are so minimal that they are not safe can differ.

Whether it is audible, another transfer, who knows, probably not. While the differences from 96 to 44.1 Khz for many more at the appropriate facility should be audible, it will probably be at 192kHz in contrast to 96kHz only very small differences. Useful and comprehensible real-studies to my knowledge there is not yet.

And the possibility of further harmonics added to (what is with high quality player with the current 44.1 kHz/16Bit-Aufnahmen indeed does) there's always more to get the last bit.

But for the recordings to be made already in this format, with originals of standard DAT (48kHz, 16bit), of course, will sound the same copy. The main problem here is the recording while it is no more problems with microphones and corresponding 24-bit DACs, which is in the synthetic pop and dance sounds, etc. something different. Since these samples do not have the required format, corresponding expense is necessary.

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