Digital audio information (Part 3)
Codec sample rate and bit depth
Sampling is the acquisition of instantaneous values (samples) of an analog signal with a certain time step in the digitization process. The frequency of this step is called the sample rate (it is also the sample or sample rate). The larger it is, the better the sound recorded and reproduced. In studio equipment, the frequency is 48 kHz, in home systems – 44.1 kHz.
Bit depth determines the quality of the recorded audio. Higher is better. The bit value, for example 32, denotes the number of bits that are allocated to record the amplitude of the signal at the time of its measurement.
Consequently, the more often (sample rate) and more accurately (bit depth) the audio signal is measured, the higher quality audio file is obtained.
Bitrate
The bit rate (literally, the information bit rate) determines the maximum amount of information that can be transmitted through the audio channel per unit of time. A high bit rate is needed to transmit a rich sound image and is not required when encoding speech. Audio recordings with a 128 Kbps bit rate are suitable for inexpensive speakers, but when accessing expensive equipment, it makes sense to get music at a 192-256 Kbps bit rate.
Convenient solution: variable bit rate encoding, change the bandwidth of the audio channel according to the quality and saturation of the musical fragment.
Audio formats
MP3 is the most popular digital audio format right now. It is widely used in file-sharing networks due to the small size of the final files (approximately 1/10 of the original audio CD file) and due to its special data compression algorithm, it provides playback quality very close to that of original. The MP3 format is compatible with absolutely all RoverMedia players, as well as all modern stereos and DVD players.
WMA is a file format developed by Microsoft to store and transmit audio information. The main advantage of WMA over MP3 is its greater compression capacity, which results in a smaller file size. The latest versions of the format, starting with Windows Media Audio 9.1, provide lossless encoding, multi-channel surround sound encoding, and speech encoding.
WAV is an audio container file format for storing a recording of a digitized audio stream. This format is mainly used to record sound from the voice recorder built into RoverMedia players and most modern devices.
FLAC (Free Lossless Audio Codec) is one of the most popular formats for lossless audio compression. Unlike MP3 and WMA formats, it does not remove any information from the audio stream when encoding the audio. Thanks to this, FLAC files are suitable not only for listening to high-quality music on RoverMedia portable media players, but even on high-quality audio equipment.
Number of audio channels
Infectious mononucleosis
Mono (from the Greek (Monos) – one) is a prefix that means the relationship with the singular.
Mono eng. Mono (monophony) is most often used as a term related to the recording and reproduction of sound.
Mono means monophonic, single channel.
Stereo
Stereo (from Greek solid, spatial)
Stereophony or stereo sound (from the ancient Greek words “stereoros” – solid, spatial and “background” – sound): recording, transmission or reproduction of sound, in which the auditory information about the location of its source is stored through sound design over two (or more) independent audio channels. …
In stereo recording, the recording is made from 2 microphones spaced a certain distance, each with a separate channel (right or left).
The result is what is called “panoramic sound”.
