Frequency used for audio (sample rate, PCM, DSD, etc.) Part 2
LRCLK
I explained that the LRCLK that came out earlier is a signal that distinguishes between L and R. In the I2S format regulations, the signal level is specified as L channel for 0V (low) and R channel for high.
Let’s take a look at the LRCLK waveform that actually corresponds to the sample rate.
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LRCLK 44.1KHz CD Playback
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LRCLK 96KHz LPCM 96 kHz playback
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LRCLK 192 KHz LPCM 192 KHz playback
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LRCLK 384 kHz LPCM 384kHz playback
Therefore, the sample rate matches LRCLK. COMBO384 supports LPCM maximum sample rate up to 384KHz.
7. BCLK
It is sometimes referred to simply as CLK, commonly referred to as a bit clock, and is the reference clock for reading 32 bits. So 32 times the sample rate and 64 times the LR channel frequency combined.
It will be the second frequency in the frequency calculation above. In the case of 44.1 KHz, it will be 2.8224 MHz.
Let’s take a look at the actual BCLK.
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BCLK 2.8224MHz CD 44.1 kHz
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BCLK 6.144MHz LPCM 96 kHz
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BCLK 12.288MHz LPCM 192 KHz
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BCLK 24.5760MHz LPCM 384kHz
This BCLK is also issued during DSD.
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DSD64 2.8224 MHz
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DSD128 5.6448 MHz
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DSD256 11.2896 MHz
It is often mentioned that it supports 11.2MHz in the introduction of DSD, but to be exact, it is this frequency.
The waveform is not square because the oscilloscope has a low frequency bandwidth. It is actually a square wave.
How was it?
Did you understand the frequencies used for the audio?
I think you can see audio frequencies in various situations, but if you remember that this frequency meant something like this, I think you may feel more familiar with digital audio.
In Marz, this DSD256 (11.2896MHz above) LPCM is 384KHz sells an amplifier equipped with a COMBO384 corresponding to.
Since it supports high sample rates, it can play high-resolution music.
Amplifier kit equipped with USB-DAC
・ Integrated Stereo Amplifier LV-2.0 PREMIUM Kit [LV2-KIT-PREMIUM]
USB-DAC module (with COMBO384)
・ LV-2.0 USB DAC Board Module Finished Product [LV2-USBDACM]
