Audio formats and frequencies: science behind the perfect sound
In the world of high fidelity audio, sound quality is essential. However, for many, understanding the different audio formats and frequencies can be confusing. In this article, we will explore in depth the most common audio formats and how frequencies affect our auditory experience, helping you to make more informed decisions about your equipment and audio files.
What do audio file formats mean?
Audio file formats are simply to store sound information.
When unprocessed audio data leaves the audio interface through the analog-digital converter, modulation by encoded impulses (PCM) is used to encode them.
To reproduce that modulation by codified impulses through a physical system, it is necessary to organize the information in a file that can be reproduced.
The types of audio file formats are distinguished by the containers that house them and the data compression methods they use to maintain the PCM flows in order.
Although these formats represent the same information, they differ in quality and storage space.
Some audio formats include unique characteristics, such as metadata storage, which provides information about content or file.
A more detailed exploration of PCM
As mentioned above, PCM, or modulation by coded impulses, is the method by which we transform analog signals into signals that can be used in the digital domain. This conversion process implies encoding waveforms with a certain depth of bits and a sampling frequency. The depth of bits refers to the number of bits per sample, while the sampling frequency indicates the number of samples taken per second.
Most digital formats usually have a 24 -bit sampling frequency/44.1 kHz.
The three main sets of audio formats can be understood simply by dividing them into three main categories:
- Non compressed audio format
- Loss compressed audio format
- Compressed audio format without loss
Comparison between audio files with loss and loss -free files
Within the vast world of audio files, there are formats with and without losses, which are distinguished by the degree of compression of the data.
Data compression is a practical tool that allows you to store more files on a hard drive. It is like condensing several individual files on the computer to create a smaller file. It is important to note that this type of compression differs significantly from the audio compression process used in the mixture or musical production.
Contrary to what is usually believed, there are data compression methods that reduce the size of the files retaining all the integrity of the information present in the audio flow. These audio formats are known as compressed formats without loss.
On the other hand, there are loss -compressed formats, which eliminate audio flow data with a minimum sound impact. However, it is important to keep in mind that this type of compression implies the loss of information.
Comparison between compressed audio formats and uncompressed audio formats
Audio formats that have not experienced any compression are known as uncompressed audio formats.
These formats act as containers that house audio data in their gross state, without any reduction in their quality or size. Although these files can occupy more space compared to tablets, they offer the highest level of detail and auditory fidelity.
They are widely used in various stages of musical production, such as recording or mixture.
However, it is important to point out that not all uncompressed audio files are identical. The quality of these files varies according to the process of conversion from the analog to digital signal. The various types of analog-digital converters use different levels of precision and accuracy.
By using a greater depth of bits and a higher sampling frequency during the conversion process, more information can be captured.
The depth of bits refers to the number of information bits present in an audio sample, which is directly related to the resolution of each sample. For example, a CD uses 16 bits per sample, while the audio of a DVD uses 24 bits per sample.
The precision with which an analog-digital converter can measure the amplitude or volume of the signal is what determines the depth of bits.
Understanding the bits rate
The bits rate refers to the amount of data produced by a file per second.
When you listen to Digital Audio, it is common to find files that carry the "KBPS" brand at the end to indicate the associated bit rate.
Every second of an audio recording contains a specific amount of bits. This amount is calculated as "data per second."
The bit rate, which represents the amount of data encoded every second, is used to evaluate the quality of a file format.
Although files with lower bit speeds are more efficient compression and smaller files, audio quality can be compromised. In the early days of hard drives and computers, when the storage space and bandwidth were limited, it was necessary to use lower bit rates.
In the current digital environment, where storage and bandwidth are less worrying, it is recommended to use the highest possible bit rate when working with compressed formats.
For example, for an MP3 file, the high quality standard is usually 320 Kbps. With this high quality configuration, it can be difficult to differentiate between compressed audio and uncompressed audio when listening casually.
High -resolution
So you may ask yourself, what about high quality audio?
High quality audio is characterized by not having a uniform standard.
However, when talking about high quality audio, producers and engineers usually refer to audio files with sampling or depth frequencies of higher than the CD standard, which is 16 bits/44.1 kHz.
For us, high quality files are found in formats such as 24 bits/48 kHz, 24 bits/96 kHz and 24 bits/192 kHz.
The advantage of high quality audio files is that they contain much more information than low quality files or compressed audio, which translates into a better sound quality. Although these files occupy more storage space, it can be worth it if you are looking for quality.
Some of the most popular high quality audio archive formats are WAV and AIFF, although there are also formats such as Flac and Alac.
Popular audio file formats
Although there are a variety of audio file formats available, some are much more common than others.
In your trip through the world of musical production, you are likely to be with only a few types of audio formats. Here are some of the main ones that you should know:
MP3
The audio format most commonly used for casual listening is MP3.
In the early 2000s, the MP3 gained popularity thanks to the revolution in the exchange of files initiated by Napster. In October 2001, Steve Jobs surprised the public by taking out a small device with 1,000 of these files.
The attractiveness of the MP3 was the ability to store a lot of information in such small containers without losing sound quality.
Of course, one of the reasons why MP3 became the epicenter of illegal music downloads was their ease of coding from CDs.
At present, MP3 are still one of the most used audio file formats. Even the main digital music download stores, such as Bandcamp, continue to use MP3 as its main format.
They are extremely convenient to store music in tablets or portable playback devices, and work in almost all playback devices.
The bits speed to which MP3 is recorded can have a great impact on sound quality. For example, an MP3 coded at 128 Kbps will have a lower sound quality than that of an MP3 encoded at 320 kbps.
AAC
AAC files are compressed audio files with loss developed by several digital technology companies, such as Bell, Microsoft and Dolby. The premise behind the creation of the AAC format is its alleged greater efficiency compared to MP3.
If you have had an iPod at some point, you are likely to have heard audio files in AAC format, since the iTunes store uses this format.
AAC is considered to be a bit more efficient than MP3, and many argue that offers a better sound quality. It is used by the Apple Music streaming platform, as well as by YouTube.
WAV/AIFF
The WAV files (Waveform Audio File Format) are one of the most popular loss or compression audio formats. Often, the AIFF files are preferred on the WAV, since both contain the same amount of information and work similarly.
Both are based on PCM (coded impulse modulation), which is one of the simplest methods for audio storage in the digital field.
The difference is that the WAV files were developed for PC users by IBM and Microsoft, and that is why they are more common on Windows platforms. WAV is also the standard coding format for CD.
On the other hand, the AIFF files (Audio Interchange File Format) were developed as an alternative to the WAV for Apple users. Although its use is not as widespread as that of the WAV, they are more compatible with metadata. Unlike WAV files, AIFF allow data inclusion such as song titles and illustrations.
Both formats use PCM, which means there is no compression or loss of information. If you work with Logic, you are likely to meet AIFF files as one of the few available options.
The main inconvenience of these formats is their large size. A CD quality file at 16 bits/44.1 KHz occupies approximately 10 MB per minute of audio.
Despite this, they are preferred formats by audio engineers who seek to keep the highest sound quality.
FLAC/ALAC/WMA
FLAC files are compressed audio files without open source losses. This audio file format was one of the first to become popular among lossless formats. Flac is an abbreviation for Free Lossless Audio Codec. These files have approximately half the size of a WAV file or Aiff standard with the same sampling frequency.
Despite their reduced size, FLAC files maintain loss quality. They even exceed the quality of a standard CD, since they can offer a resolution of up to 32 bits/96 kHz.
The advantage of FLAC files is that they allow users with storage limitations on their devices to enjoy lossless audio. Although for the average listener it can be difficult to distinguish between FLAC and MP3, many audiophiles discuss the differences.
ALAC is very similar to Flac, but was developed by Apple. These acronyms correspond to Apple Lossless Audio Codec.
ALAC is an excellent alternative to Flac for Apple Music or iOS users. However, it is important to keep in mind that Alac files tend to be slightly larger than FLAC.
The option available for Windows users is the WMA format, which refers to Windows Media Audio. This format was created by Microsoft specifically for the Windows operating system. WMA has the ability to handle sampling frequencies up to 24 bits/96 kHz, reproducing the audio without loss of data.
It is important to keep in mind that Microsoft has also developed a WMA variant with quality loss. This option can be beneficial for Windows users who wish to reduce the size of their audio files without sacrificing too much quality, compared to the MP3 format.
OGG Vorbis
The OGG Vorbis files, also known simply as Vorbis format, are compression files with loss created as an alternative to AAC and MP3. The particularity of this format is that it is not subject to any patent. The Spotify streaming service uses the OGG Vorbis format at 320 Kbps.
"OGG" does not really mean anything, and it is not a compression format in itself. Rather, it is a multimedia container designed to house a variety of compression formats. The term "OGG Vorbis" commonly refers to files that contain the Vorbis format.
Vorbis emerged in 2000 and became popular due to its association with open source software. Compared to most compression formats with loss, it offers superior audio quality.
Other types of less common audio formats
DSD
DSD is a high -resolution audio format used in CD Super Audio. It is presented in various variants, such as 2.8, 5.6 and 11.2 MHz. This format offers unreasonable audio files, ideal for quality auditory experience, although it is not very practical for streaming.
The distinctive characteristic of the DSD files is that they use only one bit, unlike uncompressed files, which use bits depth and sampling frequency. In the case of DSD files, this single bit is shown 2.8 million times per second to recreate the file.
DSD files are comparable to high resolution files of 24 bits/96 kHz in terms of sound quality. However, despite their exceptional quality, they are not widely compatible with many operating systems. In fact, a third -party D/A converter is required to use a DSD file in MAC or Windows systems.
For those who are willing to invest in an external D/A converter and appreciate the sampling quality of a single bit 2.8 million times per second, the DSD format could be interesting.
MQA
MQA is another high -resolution audio compression format without loss, designed for more efficient streaming. Tidal uses MQA for high resolution streaming, and is also used in many CDs.
How to select an audio file format
So, after assimilating all this information on audio file formats, what are you doing with it?
Choosing the appropriate audio format for each need can make a big difference.
The choice of audio format will depend on whether you value the quality of sound or storage space, as well as the devices you use for reproduction.
If you are a casual listener, you may satisfy the file formats compressed with high bit rates, such as AAC or MP3 at 320 Kbps.
On the other hand, if you are a musical producer or recording engineer, you are likely to prefer to use audio files without compressing with high sampling frequencies. The WAV and AIFF formats of 24 bits/48 kHz are popular options in this case.
However, for a serious and critical audition, many audiophiles suggest the FLAC format.
In conclusion, the information provided is invaluable for those who seek to improve audio quality on their devices. The understanding of the different high quality audio formats and the importance of having an adequate DAC for its reproduction is presented as a fundamental step in this process.
When making the decision to explore these formats, it is essential to equip yourself with a DAC that allows the optimal coding and reproduction of these files.
For more information about products that meet these needs, we invite you to consult the following link https://ifi-audio.com.mx/.
Ultimately, investing in a high quality audio system can significantly transform the auditory experience and the enjoyment of music.
