What are the sample rate, the number of quantization bits, and the clock? Part 2
The bits are a binary number in digital counting. Binary numbers are a game, and as the number of bits increases, the number that can be expressed at an accelerated rate increases (number of steps = sampling precision).
The calculation is “2 raised to the power of the bits.” For example, 3 bits would have 2 x 2 x 2 = 8 steps, but 5 bits would have 2 x 2 x 2 x 2 x 2 = 32 steps. It seems that it will be incredible if we continue like this. Yes, 16 bits is 2 to the power of 16, so multiply 2 16 times to get 65536 steps. Remember the “65,000 steps”.
Still, it’s not analog per se, but if you play it on a CD player it will play the original continuous analog wave, which is why digital is Erai. Actually, after quantization, the encoding work is done and a 16-bit PCM digital signal is obtained as “010011 … 10”.
Digital is strict and, in fact, there are some rules. It is often said that “CD has a frequency range of 20 kHz and a dynamic range of 96 dB”. This is determined solely by the format. To put it bluntly, the 20 kHz high-frequency range comes from the sample rate, while the 16-bit quantization defines the D range as 96 dB.
It’s kind of logical, but it’s called “Shannon’s Sampling Theorem (Erai scholar)”, and it can record high frequencies up to almost half the sampling frequency (fs). For quantization, there is a guideline of 6 decibels per bit, which is 6 x 16 = 96 decibels. Let’s put it on the sumikko of the head.
■ CD player sound quality enhancement technology: What are high bits and high sampling?
However, CD players have various technologies to improve the sound depending on the manufacturer. Like Denon’s AL24 processing and Pioneer’s legato link conversion. Even if the name is different for each manufacturer, it basically reproduces the subtle nuances and quirky atmosphere of the original analog audio that was cut on CD using extended technology like high bit and high sampling. It’s just a device in CD format, but when you ask, it certainly feels clear and the amount of information has increased.
So what kind of processing are you doing?
The left side of the figure is a normal CD format. The horizontal axis is incremented by fs = 44.1 kHz and the sample data is read with 16-bit precision. This is as explained above and unless there is special processing on the player side it will play as is with CD audio.
But the figure on the right is different. This is an image of the AL24 example, and the bits are expanded from the usual 16-bit to 24-bit using a dedicated chip. So a simple calculation can express a fine sound that is 2 to the eighth power, that is, 256 times. It seems that the upper and lower bits are moved and advanced things are done, but due to such bit expansion and high sampling (extending the high frequency range) like 4fs and 8fs in the direction of the horizontal axis, the squares are much smaller . Even if it is a CD, you can enjoy high-quality sound that surpasses that of a CD.
