In what format is it better to listen to music. Three whales lossy

2024 Author: Malcolm Clapton | [email protected]. Last modified: 2023-12-17 03:44

Understanding digital audio formats is not easy at all. It is even more difficult to make an unambiguous conclusion in which format it is better to listen to music. If you look at the comparative table of audio formats on Wikipedia, your eyes will start to ripple with columns of silent numbers. Let's try to figure out what is behind this.

Let's make a reservation right away that the article speaks ONLY about general characteristics and will not include some details. In the future, Lifehacker will conduct her own impartial research. And today we will try to generalize the already known experience in one way or another.

There is an analogue and a figure.

Analog is good, but short-lived and inconvenient. Therefore, analogue media, despite high vinyl sales, will not make a comeback.

Audio digital can be of three main types:

• in a format that does not use compression;
• in a format that uses lossless compression;
• in a format that uses lossy compression.

At first glance, lossless formats are more promising. This is not always the case, as we will discuss in more detail in one of the following materials. Uncompressed formats do not make any sense other than storing master recordings needed to create audio content. They are easier to restore. To store and listen to home recordings are superfluous.

Of the many parameters of digital audio, the user should first of all care about the sampling frequency (the accuracy of digitizing an analog signal in time), bit depth (the accuracy of digitizing in amplitude - loudness), bit rate (the amount of information contained in the file per second).

Today we'll talk about lossy.

For compressed sound, the concept of the psychoacoustic model is very important - the ideas of scientists and engineers about how a person perceives sound. The ear perceives the entire spectrum of acoustic waves arriving at it. However, the brain processes the signals.

The reference value of the human-audible range is from 16 Hz to 20 kHz, but he is not able to simultaneously hear and be aware of all incoming sounds.

Hearing is discrete and its auditory sensitivity is non-linear.

Modern psychoacoustic models accurately assess human hearing and are constantly improving. In fact, despite the assurances of music lovers, musicians and audiophiles, for the average untrained ear, the initial appearance of MP3 in maximum quality has become extremely perceptible. There are exceptions, they cannot but exist. But they are not always easily noticeable with blind listening.

Formats using psychoacoustic compression models

There are a lot of such formats for lossy audio compression. The most common today are the following.

OGG (Vorbis)

In general, a file with the *.ogg extension is a "container": it can contain several sound recordings with its own tags and characteristics. Most often, the files stored in it are compressed with the Ogg Vorbis codec, although others, including MP3 or FLAC, can be used.

Its main advantages include a wide range of possible parameters during encoding: the audio sampling rate can reach 192 kHz, the bit depth is 32 bits. By default, OGG uses a variable bit rate (although this is not indicated in the properties display), which can go up to 1,000 kbps.

MP3

Unlike the free OGG, MP3 was developed by the Fraunhofer Society, an association of institutes for applied research in Germany, which is very important for modern acoustics. Among audiophiles, by the way, this is an extremely respected office, however, they do not like to admit it. But their developments are closely watched.

Unlike OGG, it can have both variable (VBR) and constant bitrate (CBR). By the way, it was thanks to MP3 that it was discovered that not every recording can be encoded with high quality with a variable bitrate (see the reasons above, the encoding algorithms and their results in this case may be different when encoding the same source).

Due to its advanced age, MP3 has significant limitations: the bit depth can be 16-24 bits, the sampling frequency is expressed only in discrete values (8, 11, 025, 12, 16, 22, 05, 24, 32, 44, 1, 48), bit rate limited to 320 kbps. In addition, in the regular version of MP3, the number of channels is limited to two.

AAC

The same rake, only in profile. Also developed by the Fraunhofer Society. Later and uses a different psychoacoustic model, more modern. Publicly available information allows us to conclude: yes, they managed to improve their own creation.

Even with the most basic numbers, AAC is a more flexible format. The bit depth of the files obtained with the help of this development ranges from 16 to 24, the sampling frequency, if desired, will also allow not to lose the sound picture and lies in the range of 8-192 kHz. The data stream generally approaches those of lossless formats (up to 512 kbps), while the maximum number of AAC file channels reaches 48.

Which format is definitely the best

Considering that AAC is MP3 reimagined after a dozen years, then the choice is in its favor. If desired, it makes sense to compare only MP3 and OGG. Let's take a look at the pictures made by respected Andrey Aspidov from ixbt.com:

On the graphs - good AudioCD, compressed OGG with variable bitrate 350 kbps and MP3 using Lame. The lower the graph is, the closer the sound is to the original. It turns out to be a very interesting picture. Despite the fact that MP3 has clearly cut high frequencies, in contrast to the OGG, in which you can see the blockage below 2 kHz.

The frequency-time distribution of sound speaks of no less interesting things. At a constant bitrate of 320 kbps, the MP3 is nearly identical to the original recording. Everything seems to be falling into place now. But … In fact, everything is even more confusing.

Why use lossy at all when there is lossless available

Common sense.

The fact is that most of the analog recordings do not contain the amount of information that would need to be stored in high quality formats. Do not forget that the native sampling rate for CD is 44.1 kHz, quantization is only 16 bits.

The previous graphs demonstrate the high fidelity of MP3 transmission well. But for an audio cassette, a magnetic tape (unless, of course, this is a master tape), the characteristics of an AudioCD are unattainable. And for mass studio equipment, the ability to record analog sound corresponding to AudioCD has appeared relatively recently. It makes no sense to digitize in FLAC (and even more so in WAV) a concert recording or a disc from the pre-digital era, especially those made from magnetic media. They do not contain those spectra and the amount of information that containers without compression can store.

What has changed today

A rare sound engineer makes a digital master recording (which is then reproduced on physical media), using modern technologies to the fullest. Therefore, the chance that a 24-bit track is actually just 16-bit is extremely high.

Analog high-quality recording on high-quality equipment is even more difficult to find today - if only for fans of this sound. Such, for example, is Jack White, the ex-leader of the White Stripes. At the same time, some of his recordings refer to variations of lo-fi, and looking for the outrageous sound characteristics of the track there becomes a kind of pleasure for gourmets.

If you imagine an ideal source, then only trained ear or listening on high-quality audio equipment will allow you to find a compressed file. And already based on this (and not forgetting about perception), it is worth making the following conclusion:

AAC is necessary and sufficient for mid-priced equipment, in the absence of which (and in the absence of sources that can be encoded in AAC) - MP3 with a constant bitrate of 320 kbps, created using the Lame 3.93 codec (recommended keys for decoding: -cbr -b320 -q0 -k -ms).

The exceptions are recordings originally recorded in high quality, say, recorded on DVD-Audio, SACD, or recordings originally collected in DSD (or similar format) with a high bit rate.

Although lossless has some features. And we will tell about them next time.