What is lossless sound quality Part 8


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What is lossless sound quality Part 8

Apple Lossless Audio

In conclusion

Apple Lossless

▲The sense of hearing is an analogy with the senses, whether listening to music or returning is the pleasure of listening

It took so much space to broadcast that for different users, whether it is necessary to deliberately pursue the quality of music files, hardware or technology varies from person to person, although it is often seen that different factions of consumer groups ridicule each other. Specific technology or hardware chased each other, but listening to music ultimately returns to the personal analogy, you can hear the difference does not mean that other people can also hear the difference, what you do not mind does not mean that others do not I do not care, I just want listen to her Music is more important than anything else, and there is no need to force others to accept it.

From the previous list, the author believes that the most direct difference for users will be the introduction of spatial audio, followed by a certain level of listening in terminal equipment (headphones or speakers); a bit more advanced is the autocompression format and the search for the lossless compression format. At the same time, the external audio equipment is adequately expanded to replace the built-in equipment; for gamers who have a strong sense of hearing and attach great importance to seeking the latest, they will have more needs for high-quality files, Bit-Perfect, etc.

 

▲A high-end smartphone with a headphone jack is relatively convenient for listening to high-quality music. After all, external devices will increase the volume.

However, the author still wants to say that discarding the headphone jack in high-end mobile phones is really a very wrong decision for users who need to listen to music, since the price of wireless headphones with the same sound quality is even higher. than that of wired headphones. Interference, lag, battery life, etc. make listening to music troublesome. It is also extremely inconvenient to use an additional conversion cable to convert it to a 3.5mm output. As far as the author is concerned nowadays, the music is almost never left during the work, but instead of focusing on listening to the details, the author believes that in this situation, as long as there is a certain quality of interpretation, the search for a better sound quality is already a consequence. get out of work enjoy.


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What is lossless sound quality Part 7

What is lossless sound quality Part 7

Apple Music lossless

Assuming you really have a good sense of hearing, investing in better hearing equipment may be the most straightforward option.

Lossless audio

According to the author’s experience, headphones with a certain level can help you hear the details and dynamics of music, and even if the mobile phone can support lossless files The occupation mode matches the Bit-Perfect playback output, and the listening experience is still not as good as using SRC mode with a slightly higher level external audio device. After all, the external audio device has relatively ideal circuit isolation and higher quality audio grade components and a more abundant driving force will make the music heard in the headphones more layered and full.

However, the sound here refers to the form of the sound. If you listen to the compressed file with a better external audio device, you will find that the sound connection is still quite broken and the fineness is not ideal. The atmosphere is better without being noticed at first glance, but looking back, how many opportunities and moods are there to listen to the details so carefully, so if the author chooses, the author will still give priority to improving the quality of the headphones and external audio equipment. quality.

Why Apple believes that spatial audio is a technology that can lead the music trend more than high-quality sound

▲ The focus of spatial audio is to break the limitation of listening to the left and right channels of stereo headphones, making the listening feeling more three-dimensional

The last thing I have to mention is that Apple put support for spatial audio technology before providing high-quality sound in the Apple Music revision. One, of course, is that Apple hasn’t completed the SRC of the playback software, and most people can’t distinguish between lossless and compression sound quality. The difference in sound quality is no coincidence that Sony is also promoting 360 Reality Audio technology with similar features. It can be said that the important point of spatial audio technology is to break through stereo and even break through the innate limitations of headphones.

Because compared to the speakers that are placed in an open space and transmit the sound by direct exposure and reflection in space, and finally heard by the human ear and produce a sense of space, the headphones directly connect the left channel and the right channel. right. is transmitted to the left ear and right ear, but the earphone will not be able to hear a part of the right sound as a speaker, and the right ear can also hear a part of the sound from the left ear. This is also the key for many music players who believe that speakers still appreciate more than headphones.

▲ Sony’s 360RA is further corrected for ear type data and can be optimized for specific headphones and speakers

But after all, most of today’s music formats use stereo as a reference point, but do not take into account the differences between headphones and sound devices. Once recorded in traditional stereo, it is difficult to change the innate limitation of the headphone listening experience; The technology allows headphones to simulate the flat sound field of speakers, but in analog, sometimes the spatial position of the sound gets weird.

Whether it’s Dolby Atmos, which is the basis of Apple’s spatial audio technology, or Sony’s 360 Reality Audio, in the post-production process, the music creator defines the sound space and uses analog technology to create the corresponding frequency in the sense of hearing It can not only overcome the flat sound field of traditional virtual surround sound, but also because it is a real spatial positioning narrative, it can also hear the listening feeling that is closer to the original creator’s desire to express.

To listen to music with headphones, it can help break the original stereo playback positioning method, so that at first glance the sound can be as three-dimensional as using a speaker, and the user’s sense of hearing will be more direct than enhancing the details . Of music It is also easier to feel the difference with the general public’s sense of hearing, of course, spatial audio technology is also suitable for multi-channel speaker systems, and multi-channel speaker system and spatial audio is expected they complement each other.

What is lossless sound quality Part 6

What is lossless sound quality Part 6

LOSSLESS AUDIO

Only a few third-party playback programs can exclusively bypass SRC on external sound devices.

Apple Music Lossless

From the author’s personal test with an Android mobile phone, once an external audio device is connected, if the playback software that follows Google’s standard music playback API is used (usually the default music playback software mobile phone), the result will be the following 24bit 48kHz.

The format will be forced to convert to 24bit 48kHz, but music with a format higher than 24bit 96kHz can be output normally. As for the KKBOX app, the speed is limited to 24bit 48kHz. If you want to play the native format on Android through an external audio device, you still need to rely on third-party music player software with USB Bit-Perfect function, such as Haibei Music. At the same time, manual settings are required, which is complicated for ordinary consumers.

Is the quality of the file important, being able to do exclusive mode and Bit-Perfect, or the sound quality of the device itself?

▲ Even if it is CD sound quality, exclusive mode playback may be clearer than SRC

Although much has been mentioned above, from the most fundamental point of view, is it important to need high quality audio files, or is it important to be able to decode and play at the native sample rate, or is the audio structure of the device important in itself and the headphones and speakers used to listen? Ideally, I’d have it all, but if I’m limited, I always have to choose.

Let’s start with the quality of the files. CD specs at that time will be set to 16-bit 44.1kHz, which is based on the sound that the human ear can theoretically hear in the 20-20kHz range. Angles are less audible, and people with better hearing can “feel” more nuance. But if you look at the listening density, the compression format will be different from original sound quality/lossless compression.

▲Compared to using a mobile phone to play lossless sound quality, playing 320K AAC with a high-end player or external DAC sounds more pleasant at first glance

For a 16-bit 44.1 kHz piece of music in the conventional original WAVE format, the overall encoding stream is about 1.4 Mbps. As for the use of lossless compression, it will vary depending on the complexity of the song and will typically be between 600kbps and 1Mbps. However, the lossy compression format will be less than 320kbps, which means that since the original file is destroyed and compressed down to 320kbps, at least almost 3 /4 of the information is destroyed, and in terms of PCM characteristics, it is equivalent to the signal. The middle of the curve is greatly reduced, returning to the sense of hearing means that the dynamics of the music are reduced, and the connection between sound and sound is broken.

It is absolutely important whether or not to use Bit-Perfect in exclusive mode. The author thinks that if you only listen to CD quality and destroy the compressed format, it is a relatively harmless situation, because the essence of the destroyed compression format is to use CD samples as a model for compression. Generally, the default value of SRC provides enough flow for CD, although the actual information through SRC is not forced to drop because of SRC, but rather because the input signal must be shared with other applications. , the sound seems to be covered in comparison.A layer of thread.

▲With the right gear, hear the dynamics and connection of native hi-res music

But if you’re pretty sure of your hearing, the key difference between playing music in exclusive mode with Bit-Perfect is playing hi-res music, because if you use SRC, it will force the original amount of information and dynamics to be in SRC.After being erased, the sound quality is the same as listening to the CD, and the original harmonics will also disappear, but the premise is that the user must have the corresponding equipment and the sense of hearing that can feel the harmonics. For example, the Vic

What is lossless sound quality Part 5

What is lossless sound quality Part 5

Apple Music Lossless

Web-based players are often difficult to bypass SRC restrictions

Apple Music Lossless

What is the function of SRC? In a nutshell, it is to first convert all current output sounds from the device to a fixed sample rate, whether CD quality or high quality, etc., and perform pre-processing equal to a rate, so that the sample rate device sound can be decoded at the same time Process audio for a large number of applications and systems. But the problem of SRC is that PC and mobile devices can’t hear the real high-quality sound, and even CD-quality music will sound exhausted. After SRC, even if the music is played losslessly, it will be processed in CD-quality data The external device is equipped with a monitor panel, and you can also see that the sound quality is 24bit 96kHz, but it is processed in SRC 16bit 48kHz (Note: SRC can be set manually in the PC system for sampling).

▲On mobile devices, the app must also have an exclusive mode to not be restricted by SRC

Simply put, because SRC will convert digital audio from various applications and systems before it is decoded by the input audio device, and all sounds will be compressed into the same input signal, regardless of music, sound effects, etc. the movies etc. is boosting, cutting, or the same frequency as the SRC, the above signal processing is a kind of loss, which will eventually make the sound less than the original appearance.

▲ Although KKBOX can bypass the SRC restriction in certain versions of Android system, it will be blocked when an external sound card is connected.

In order to allow PC systems and mobile devices to play the original level of music files, they must be played in Bit-Perfect mode through the audio device’s exclusive mode, but most general-purpose music playback software and web-based music software do not have this feature. . Audio device exclusive mode and Bit-Perfect, respectively, allow the playback software to bypass the SRC mechanism and get the sole right of input from the audio output device, which is equivalent to sound effects in other systems that cannot be produced exclusively by the device. general public explains why there is only music left, and not even YouTube videos.

Mentioned in photo) Sound, Q Speaker – Content, Playback, Contains screenshots, Sony HW700DS, Computer, Software, PlayStation 4

▲Although the SRC setting can be fixed to high sound quality, both compressed music and high sound quality music need to be reprocessed, and the sound quality will be damaged

Currently, there are many professional music playback software on PC or music software provided by audio equipment that can play music in exclusive mode. For example, KKBOX has also completed the configuration function of exclusive mode and Bit-Perfect version driver in the latest version for PC. Mobile devices are more embarrassing. In recent versions, Apple and Google allow exclusive and Bit-Perfect playback of built-in audio devices, but it gets complicated when it comes to external audio devices.

What is lossless sound quality Part 4

What is lossless sound quality Part 4

lossless audio

However, there are many early music recordings that also provide high-quality files in the process of being digitized, but in theory there is no such thing as high-quality digital radio at the time this record was released. How did these files come about?

Lossless Audio

 

Broadly speaking, early digital mastering music can be divided into analog mastering and CD-level digital mastering with upscaling; Since the waveform of the analog audio signal can present a real smooth curve, it can be achieved through suitable analog digital conversion equipment. Achieve the information density of the high-resolution level, but after all, we have to consider the high and low frequency limit of the radio equipment in the recording era, so the expressive power of high and low frequency is not necessarily better than modern recording.

As for the expansion of CD-level master tapes, most of them will be marked Remaster. This type of file is presented by combining CD-level sound quality files through post-production upscaling and mixing technology. However, the effects of the Remaster files in different periods appear different, but also affected by the personal preferences of the sound engineer who carried out the Remaster project. Some players think that after the Remaster, although the amount of musical information is gets bigger, at the same time, the musicality can be worse than the original CD.

The innate limitations of listening to music through mobile phones and computers and the high-quality sound you hear may not be the high-quality sound you think.
EVGA., HTR are mentioned in the photo, including car, car, car design, design, car engineering

▲Perhaps many people do not know that even if a 32-bit sound card is installed, the actual listening format is due to the SRC card in CD quality.

Coming back to music playback itself, the current mainstream of digital music playback has shifted from traditional players to PC platforms and smart mobile devices, but some people may be confused as to why music performance seems strange. heard on a computer or mobile phone. At the same time, people who are fairly confident in their hearing and can tell a CD from high-quality music on a stand-alone player have difficulty telling the difference in CD quality when listening to high-quality content on a computer.

▲To bypass SRC, you need to use playback software and sound driver mode that supports exclusive mode, but most music playback software does not have this function

The reason for the limited listening experience on mobile devices and PC platforms is that these devices are embedded systems, and the audio output on the device is shared with multiple applications, including the system itself, the browser, and each separate application. time, these sounds are often sent synchronously, so modern operating systems will provide an audio device sharing mode called SRC for audio, in order to prevent the audio chip from inserting different audio formats and not can be decoded.

What is lossless sound quality Part 3

What is lossless sound quality Part 3

Apple Music Lossless: What Devices are Supported? - MacRumors

Although the sense of sound can be quantified through data, it has always been a subjective awareness.

Qué es Apple Music sin pérdidas y qué dispositivos funcionan?

However, apart from the difference in the sense of human hearing, the quality of each piece of music still goes back to the original recording and after recording. production; Many years ago, Sony started promoting high-quality music. When it comes to music and sound quality equipment, the author once talked to a senior engineer at Sony about the difference high quality sound makes to the listener. At that time, the senior engineer pointed out that from the data plane, the high-quality sound format is actually a large extension of high-frequency. However, if you ditch the data specs and record high-quality music with modern equipment, you’ll be able to present deeper, more realistic low-frequency dynamics.

The photo contains electronic accessories, electronics, Sony Walkman NW-WM1 series, Sony DMP-Z1, headphones

▲Although the quality of the original sound is very important, even a well-recorded 320K file with a good playback and listening device can work better than directly using a mobile phone to play a high-quality file with the included headphones

However, this is also seen from the original conditions of the radio equipment, but generally the music released to the market will not be released directly after being picked up. The original audio still needs to go through steps like re-editing, post-production. , synthesis, etc.. The music post-production process will also degrade the sound quality and involve personal preferences. If the editing is excessive, the sound quality will also be affected.

However, if the WAVE format, which is commonly used in standard digital music, is used, no matter what the result of the front recording is and how damaged it is, the music will eventually be compressed into a file with a fixed format. sampling rate, but the content will also include a large amount of inaudible information. ; As for the lossless compression of FLAC, AAC, etc., the sound psychology theory removes information that can be considered non-existent, so that the file can be simplified.

OTOTOY is mentioned in the photo, There is a sound you can’t bru-, Genre Main > Best Selling Album Best Selling EP Latest Release Featured Item Music Information Merchandise Sale IN STORE OTOTOY Academy, including web pages, multimedia, online advertising, computer programs, product

▲ The new generation of recording methods will also use the 24-bit 44.1 kHz or higher format, which can record richer details (Image taken from: Ototoy)

Before we go on to mention high-quality sound, let’s talk about the changes related to recording in recent years; With the improvement of digital recording technology in recent years, the front recording project has also begun to introduce high-quality sound recording to exceed the traditional CD sound quality 16-bit 44.1kHz sampling above 24-bit 44.1 kHz The format is used like the original master tape, although it can only be increased from 16-bit to 24-bit, but the increased amount of data per second means there is more information. If the subsequent sampling rate is increased to 96 bits, the PCM encoded sound curve of the sawtooth waveform can be improved. Close to analog waveforms.

For example, the Japanese digital music platform Ototoy will mark such music based on high-quality recordings with the HQD symbol. Before the term Hi-Res Audio, this type of 24-bit audio based on high-quality recordings and not re-pressed into CD-quality sound. The file is usually completed with a digital mastering level sound quality file, and has been in practice for many years before the appearance of the hi-res level mark. Incidentally, SACDs recorded in 1-bit format and presented in DSD format that is close to an analog curve can also be considered as mastering. It is a kind of high-quality sound quality, but strictly speaking, since the DSD format does not have the editing function, in fact, the DSD file is still converted as a high-density PCM file.

9:41, all colors are mentioned in the photo, including Apple Music Lossless Android, Lossless Compression, Apple Music, Dolby Atmos, 3D Sound

▲Currently, high-resolution music is divided into analog mastering transcription, CD-quality mastering scaling, and high-quality native sound mastering, among which the scaling effect is still the worst

What is lossless sound quality Part 2

What is lossless sound quality Part 2

lossless audio

The principle of these audio compression methods is to preserve places that are easily heard by the human ear as much as possible.

 

Music Lossless

 

In conventional fixed bit rate (CBR) mode, the audible data in the audio is removed and is easier for the human ear to hear. The more information that is withheld, the less information that is withheld when the part is inaudible. As the complexity of the sound increases, the degree of deterioration in sound quality becomes more apparent. For example, when listening to pure voice Performances and performances combined with background music, pure compressed music for vocals, sounds less degraded than the original file.

As for the lossless sound quality offered by the current streaming platform, there are many formats, but in fact, strictly speaking, these formats, including flac and ALAC, belong to lossless compression (non-destructive data compression) in place of lossless sound quality in a strict sense. The performance is almost the same as WAVE, but the file size is small, the decoding speed is fast, and at the same time, it can be used in streaming services. Therefore, it is also the representative format of lossless sound quality entering the era of non-optical disc media, and it is also the current music streaming service.

In addition, Tidal’s MQA is a more controversial format, because although MQA is general lossless audio reduction, it focuses on making high quality music files higher than CD quality so that they are similar to files. CD-quality flac. original high-quality sound format, but the point of controversy is whether the higher compression ratio can maintain the same real listening experience as the original high-quality sound quality has been controversial, and MQA requires a specific device to perform the hardware decoding. many devices are still only able to do MQA decoding through software.

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▲Today’s so-called High-Resolution Audio generally refers to sound quality above CD, but to be certified, the device must support 24-bit, 96kHz format processing capability.

However, since MP3 and AAC are previously planned destructive music compression formats, their purpose is to compress CD-level sound quality into smaller files, so most of the encoding specifications are presented in one presentation. 16-bit 44.1 kHz or 16-bit 48 kHz CD-level audio, but MQA is a format with a reduced file size that blocks high-quality sound. Basically, the MQA format will be equivalent to PCM 24-bit or top music.

In fact, with that said, current music file formats that don’t emphasize high-quality streaming services, whether presented in MP3 or AAC, are called lossy-compressed music, while high-quality, lossless streaming quality is compressed without loss. music. As for the music heard by traditional vehicles like vinyl and CD, it is called lossless music. In theory, non-destructively compressed lossless music and lossless music should have the same sound quality.

Does lossless sound quality have to be good? Does compressed sound have to be bad?
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▲ Although Apple Music has released lossless sound quality, its marketing focus is on spatial audio

When the Japanese audio industry started promoting high-quality music, many people jumped up and said that high-quality sound was useless. When Apple Music launched the premium sound format, its executives also said that he was one of the people who couldn’t tell the difference, noting that Apple launched the premium sound service to serve one of those hundred people. ; Before we talk about high-quality sound, let’s go back and talk about the current state of digital music on today’s playback devices. .

What is lossless sound quality

What is lossless sound quality

lossless

There is no comparison, no harm, if lossless sound quality and high sound quality are necessary, and what differences in hearing can Bit-Perfect bring without going through SRC

lossless & lossless audio

mp3

CD

KKBOX

flac

spotify

high resolution

dolby atmos

Apple

apple music

CAA

360 reality audio

SRC

spatial audio

Bit-Perfect

Although lossless sound quality and high-quality streaming services have been on the market for a while, as have true wireless earphones, Apple isn’t the first to make waves in the market, with Apple’s launch of so-called high-fidelity compressed sound quality. in Apple Music, in fact, after the lossless compression commonly known in Taiwan’s audio industry, lossless sound quality and high sound quality have instantly become a hot topic discussed by many people, but if the benefits of lossless sound quality are really obvious, the author will spend some space from the theoretical concept to the practical level. The differences are briefly described, but the following arguments focus on being easy to understand, so some of the descriptions are not entirely accurate.

What is lossless sound quality? What is the sound quality of the music we usually listen to?
The photo mentions * Introduction to KKBOX sound quality (including format), release year, sound quality, including digital, KKBox, streaming, Hi-Res Audio and Hi-Fi

▲ Both AAC and MP3 are destructive compression, while FLAC and ALAC are lossless compression

Before we go into the details, let’s talk about what is called lossless sound quality; From the author’s concept and cognition, the so-called lossless sound quality is a relative word rather than an absolute word. The main source is the relative word born due to the emergence of the MP3 music compression format. ; After the music industry entered the digital format, digital music files were generally recorded through PCM encoding, and WAVE files were generally used on CDs. The time and space situation of MP3 was Due to the fact that the capacity of the hard disk was generally not large at that time, in order to be limited in the limited space, a large amount of music data is stored in the storage space and you may need to compress the files. .

The reason why MP3 cannot be called a lossless format is because its essence is to compress the original WAVE file with a limited bit rate by combining concepts such as the psychology of sound. In bitrate compression mode, compared to the original WAVE file, the bitrate is at least 1:4 to 12:1. The higher the bitrate, the greater the amount of information retained. For example, AAC format also uses similar audio psychology for compression, but the efficiency is better than MP3. Therefore, the lossless sound quality of most streaming platforms today is mostly AAC as the mainstream.

Photo mentions KKBOX, FLAC format, 16bit/48kHz, related to KKBox, including kkbox Hi-Res, Hi-Res Audio, KKBox, Streaming Media, Hi-Fi

▲ Although the waveform of digital music in PCM format will appear jagged, but as the sampling rate increases, it will be closer to the analog arc curve

What is lossless? Part 3

What is lossless? Part 3

Apple Music lossless

AAC abbreviation

Apple Music lossless

Advanced Audio Coding. Lossy compressed audio file format used by the iTunes Store. The extension is “.m4a”. One of the audio data compression methods included in the video data succeeding MP3 (MPEG-1 Audio Layer-3), which is a method of compressing audio data. The number of quantization bits/sampling rate supports up to 24 bits/96 kHz. However, due to lossy compression, the sound quality is lower than lossless or uncompressed audio files. Also, because it is a lossy compression, it is not called lossless or high resolution.

If I compare AAC with a letter,
I wrote a message on a new sheet of paper, but I wanted to inform the other party of the important things as soon as possible, so I cut the “beginning/end” of “beginning/middle/end” with scissors and only the ” naka”. To pass to The person receiving the letter reads the letters without knowing what the new paper and “Begin/End” text is like.

● Click here for a more detailed explanation of the above audio codec.

■ An audio codec is
a device or software that encodes sent data in the format of an audio file and decodes the encoded data back to its original state.

Let’s compare the sound quality.
How do you listen to “ALAC lossless”, “ALAC hi-res” and “AAC”? This time the singer-songwriter Moeka Giga appeared and she made us experiment listening and comparing the sound quality. We will deliver a realistic voice of Moeka Giga, if the way the sound is actually heard differs depending on the format of the sound source.

What is lossless? Part 2

What is lossless? Part 2

lossless

Lossy compressed sound source ⇒ Typical format: AAC, MP3

Lossless Aplee Music

Lossy Compressed Sound Font Illustration
A format that cuts out sounds that are difficult for human audiovisual to hear and compresses the capacity to a small size. Sound quality is sacrificed and deteriorated by that amount. Since the data is actually cut, once compressed, the original sound quality will not be restored even if you return to the uncompressed format.

■ What is compression?:
Reduce the capacity of data that contains a large amount of information and preserve it as much as possible.
Also, compression can reduce the load on the terminal, but the quality is lower than the original information because the capacity is reduced.

audio codec
Abbreviation for ALAC
Apple Lossless Audio Codec. Lossless compression audio file format used in “Apple Music” music and video distribution service developed by Apple and iTunes in media player. The extension is “.m4a”. The number of quantization bits is 16, 20, 24, 32 bits. The sample rate supports from 1kHz to 384kHz. (In OTOTOY, the number of quantization bits/sampling frequency supports up to 32 integer bits/384 kHz)

If you compare ALAC with a letter,
write a message on new paper, fold it vertically and hand it to the other party. The person receiving the letter can open it when he knows that it is folded once vertically. However, after the paper is folded, a single wrinkle is formed, and although it cannot be read in the state of new paper, the characters can be read firmly.

Abbreviation for FLAC
Free Lossless Audio Codec. A lossless compressed audio file format provided free of charge. The extension is “.flac”. The number of quantization bits is from 4 bits to 32 bits. The sample rate supports from 1 Hz to 655.3 kHz. (In OTOTOY, the number of quantization bits/sampling frequency supports up to 24bit/192kHz)

If you compare FLAC with a letter, the
situation is similar to ALAC. To explain the difference, FLAC is a state where the card is folded sideways. Also, the recipient can tell that it is folded to one side and open it.

WAV
A type of RIFF (Resource Interchange File Format), which is an audio file format jointly developed by Microsoft and IBM, and defines a method of storing various data in a file. It is generally an uncompressed audio file format, but the data format is free and it is also possible to store compressed data such as MP3 and WMA. In RIFF, the identifier is “WAVE”, but the extension is “.wav”, and it has come to be called WAV to distinguish the pronunciation sound from the web.

If you compare WAV with a letter,
write a message on new paper and deliver it to the other party without wrinkles. The person receiving the letter can read the letters in new paper condition.