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Let’s talk about “musical dynamics” and “musical loudness” Part 2

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Let’s talk about “musical dynamics” and “musical loudness” Part 2

The two brief examples above are to tell you that frequency content, sound pressure, and sound duration will affect people’s perception of sound volume.

That is why it is said that “loudness tends to human subjective perception”.

Since the volume is the subjective perception of people, how to quantify it?

To quantify “loudness”, the first thing you need to look at is the relationship between the frequency and the loudness of the human ear. There are two pictures below, you can read them carefully for reference:

Looking at the two images above, you will clearly see that the human ear and the human brain are not an organ that flattens the receiving frequency. It will not develop here. For the basis of loudness quantization, see the second image, there is a unit called “fon”. The phon unit is an attempt to quantize loudness. We take a 1kHz signal as an example, and it can be perceived at a volume of 40dB at 1kHz, so it is 40phon. Based on this, another unit is called a sone, 1 sone = 40phon. Both are units that attempt to quantify volume.

The international organization will be the ITU and the EBU…etc. The characteristics of the human ear, the psychoacoustics of the human brain, etc., all factors that affect loudness perception are considered together, and these factors are calculated through complicated mathematical calculations Define and standardize the reasonable loudness range for ” sound reproduction” only after statistically significant results have been obtained. Those interested can search: “ITU-R 1770 and ITU-R 1771”.

Should the rules be followed?

Of course continue! In fact, there is such a problem in Taiwan. Not to mention music, only the fourth channel and MOD, the sound level of each channel is different! The scariest thing is switching from the movie station to the shopping channel and often still being scared by the sudden volume of the shopping channel. Even radio shows have this kind of situation.

Here, you can go to Google again: “Volume War Loudness War”. All this is commonplace. This article is mainly to introduce the definition and specification of loudness.

Effects of loudness specifications

Although ITU, EBU, ISO, ANSI and other organizations have introduced loudness specifications, major music and video streaming platforms still have their own standards. However, the standards of the main platforms will continue to be around the specifications, and there will be no big or outside. When it comes to the audiovisual industry, it will generally affect these things:

Music streaming platforms: Records must meet loudness specifications at time of release

Video streaming platforms: Loudness specifications must be met when movies are released

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Let’s talk about “musical dynamics” and “musical sonority”

Where does the music we listen to come from?

Before we talk about it, it is necessary to quickly talk about the disc creation process. In principle, it can be divided into three parts: the initial stage, the intermediate stage and the later stage.

First stage: compose, arrange

Middle term: recording, mixing

Post: post mastering, distribution, marketing

Whether a piece of music is good or not can be determined at the initial stage of the arrangement. Then there is the recording. The recording process can be finding real musicians to record the sound of real instruments, or completing the melody required by the arrangement through software instruments. Then find a singer or singers to sing… and so on. This process is called recording.

The “balance” of a song is not only achieving the balance of the melody in the arrangement, on the other hand, it is leaning on the mix to make the recorded elements a harmony in listening and frequency, it is also usually necessary to coordinate It depends on where the track goes, or what the producer wants. After all, the purpose of a song or album is to become a commercial release, and the post-production and embellishment processes that need to be done are necessary.

Usually the post-mastering process will be done last. After the entire album’s timbre direction, volume adjustment and minor flaws etc. are fixed, the final mastering will be uploaded according to the loudness specifications required by each streaming platform. .

Quantify the volume and intensity of what we hear

Sometimes people equate loudness with loudness. Actually the two are different. They are different and at the same time influence each other.

Loudness can be quantified, in simple terms, it is our most used “decibel dB”. Volume, on the other hand, tends to be subjectively perceived by people. how to say? Different 75-decibel musical signals are sent out at a time, and everyone has different feelings about its loudness and volume.

Because loudness is related to three things: frequency content, duration, and sound pressure.

We played a 1000 Hz test signal for three minutes at a sound pressure of 80 decibels. Your perception of the volume of this signal will be very different from playing it for 10 seconds or 30 seconds.

Let us take two singers as an example, one of them has a more evident timbre in the mid-high frequency band, and the other has a more evident mid-low frequency band, they sing the same song, and they sing with the same key and similar sound pressure, generally in the mid-high frequency band. The sound of the sound will feel stronger.

Loudness normalization

When you have a lot of mp3 files, you often look for loudness normalization.

What usually happens is that we have mp3s (although Mp4Gain can do Loudness normalization of many other audio and video formats!!) that have been created with different settings, for example different bit rates… which causes them to have a loudness different and that is annoying to the ear.

Many times we have been collecting mp3s from different sources, finding one here and another there and over time we have managed to have a good collection that is worth thinking about, but we have a problem: the loudness differs between different music or video files.

And this has generated that we desperately need to find a solution.

Mp4Gain is the result of many years of experience and is definitely the best normalizer out there, I have no doubt.

Even for very advanced users, it offers different settings to adjust exactly what you are looking for. Pewreo if you are a common user, you will not need anything, just load the song or video (you can normalize one or hundreds at the same time) and click a button, it’s that simple.

Normalization of an audio file.

Normalization is used to increase or decrease the level of the song as a whole, so that its maximum volume peaks assume the indicated level.

Loudness Normalization

For example, if the maximum intensity points of the song are -3 dB (therefore well below 0, which should represent the maximum before distortion), normalizing to 0 dB means increasing the level of the entire song so that these peaks reach 0 dB.

This is the typical normalization of the peaks.

There is also RMS normalization (which takes into account not the peaks but the actual average level of the song).

Audio Normalization

AUDIO CDs, which have good dynamic possibilities (various intensity tones, from pianissimo to fortissimo), are generally recorded so that the maximum volume points are at 0 dB.

Normalizing your WAV recordings can be helpful in adjusting them to the average level of a CD in case they are too low (because you had been careful in level during recording) but one important thing to note:

Normalization of this type alters the original dynamics, that is, the reciprocal relationships between weak and strong sounds.

Although all levels are raised by the same amount, the relationship between 2 levels changes (small mathematical example:
2/5 = 0.4 ma (2 + 1) / (5 + 1) = 0.5 …

The result is that the weaker sounds, after abrupt normalization, sound much louder and those that were already playing only sound a little louder … altering the dynamic relationships that had been envisioned by those who originally recorded the music and making the sound output to lose depth.

Some types of music, generally already deficient dynamics (rock, metal, etc.) since the excursions between the minimum and maximum volume are almost never very consistent, are more “normalizable” without problems, while the genres in which there may be Large Dynamic excursions (classical music or music with passages from pianissimi to fortissimi) are more problematic.

In addition, it is necessary to take into account that if you normalize a large wav file that contains many songs (not yet divided) there can still be, even in genres with little dynamics, substantial differences, in this case between one song and another and not between different points of the same song.

So a light normalization can do and is actually used (to raise the level of the part), but it would be better to make sure you don’t need it (recording from the beginning with a good level) or at least not have too much. remember, however, that the dynamics are somewhat flattened.

Normalize with Mp4Gain

This software is capable (it is the only one that can do this) of normalizing the main audio and video formats and its standardization algorithm is by far the most efficient and the one that produces the best results.
For this reason it is used by musicians, radio broadcasters, universities, television stations, producers, etc.

Audio normalization explained

Audio normalization – Audio normalization

Audio normalization is the application of a constant amount of amplification of a sound recording to bring the amplitude of a target level (standard). Because the same amount of gain over the entire recording, the signal-to-noise ratio and relative dynamics are unchanged.

Two basic types of audio normalization exist. Peak normalization adjusts the recording based on the highest signal level present in the recording. Loudness normalization adjusts the recording based on perceived loudness.

Normalization differs from dynamics compression, which applies varying levels of gain across a recording to fit the level within a minimum and maximum range. Normalization adjusts the gain with a constant value over the entire recording.

Normalization is one of the functions usually provided by a digital audio workstation.

Peak normalization

One type of normalization is peak normalization, where the gain is changed to bring the highest PCM sample value or analog signal peak to a certain level – usually 0 dBFS the loudest level allowed in a digital system.

Peak normalization

Since it only goes to the highest level, only peak normalization does not take into account the apparent loudness of the content. As such, peak normalization is commonly used to change the volume so as to ensure optimal use of the available dynamic range during the mastering phase of a digital recording. In combination with compression / restriction, however, peak normalization becomes a feature that can provide a volume advantage over off-peak normalized material. This feature of digital recording systems, compression and limiting followed by peak normalization, sets contemporary trends in program loudness.

Loudness normalization

Another type of normalization is based on a measurement of loudness, where the gain is changed to bring the average amplitude to a target level. This average can be a simple measurement of average power, such as the RMS value, or it can be a measure of human perceived loudness, such as that offered by ReplayGain, Soundcheck and EBU R128.

Loudness Normalization

For example, YouTube reference level -14 LUFS, so if a program analyzed at -10 LUFS, YouTube will decrease the level 4 dB to the reference of -14 LUFS.

Loudness normalization was made in different volume combat when listening to different music in a series. Before loudness normalization, one song in a playlist would be quieter than the rest, so the end listener would have to put a volume knob to adjust the playback volume.

Depending on the dynamic range of the content and the target level, loudness normalization may result in peaks that exceed the storage medium. Software offering such normalization usually offers the option of using dynamic range compression to avoid clipping when this happens. In this situation, signal-to-noise ratio and relative dynamics changed.

Volume normalization, an explanation

Audio Normalization: Make Your Audio & Video Consistently Loud

Audio normalization is a process in which the amplitude (volume) of an audio recording is increased or decreased in a constant relationship over time, so that the maximum amplitude or the maximum effective value or the perceived volume (volume) reaches a predetermined level, the standard. If the signal has multiple tracks, they all undergo the same correction.

Normalize Audio

Example: normalization of peaks to -3 dB:
A collection of digital recordings is made with a peak modulation standard of -3dB FS.
A new stereo recording is measured. The highest maximum level is -5.5 dB FS on the left track, -5.7 dB FS on the right track.
Normalization consists of applying a constant gain of 5.5 – 3 = 2.5 dB.
Standardization requires two passes. The first determines the maximum level, the second applies the correction to the entire recording.

Audio Normalization

Maximum normalization changes the level, but not the dynamics of the sound.
Volume normalization or perception of loudness often includes compression that changes the dynamics of sound.

Peak normalization

Peak normalization applies a constant gain to a recording to bring the highest peak to a target level, 89% professional audio (-1 dBFS true peak (True Peak)).

The sound dynamics of the recording are more or less preserved, except that maintaining a low distortion level after multiplication of all samples may involve the application of a known quantization error decorrelation noise. under the name redithering (tingling of the least significant bit) 2, which slightly increases the background noise level.

Volume normalization

The purpose of volume normalization is to bring all sound elements in a collection to the same sound volume level, so you can hear them without having to adjust the volume. In fact, the normalization of the maximum level in no way guarantees a homogeneity of the perceived sound volume (Loudness).

A simple approach to volume normalization, which is provided by various software programs, is to normalize the RMS value of the integrated signal within a few tenths of a second. The most advanced machines use extensive algorithms for more accurate evaluation of the perceived noise level. The European Broadcasting Union published a recommendation 1 in 2011, which provides a relatively simple method for this evaluation.

If the standard is not low enough, volume normalization involves compression for recordings whose sound dynamics would be higher than implied when setting the standard from the maximum level. If not, the signal peaks would exceed the quantization limits.

In the simplest implementation, volume normalization collects volume data during the first pass, determines the gain or attenuation necessary for the maximum volume to reach the norm, and applies this correction to the second pass. If the elements of the collection have the same characteristics, from form factor to top factor and dynamics, as is the case with popular music collections or recorded speech, this approach produces satisfactory results.

Extensive implementations use a standard that includes not only the volume of the sound, but also the maximum maximum values and dynamics of the sound. They collect loudness levels and maximum values

VOLUME NORMALIZATION: WHAT IS THE VOLUME NORMALIZATION FUNCTION?

Audio Normalization

HOW IS THE VOLUME BETWEEN TITLES NORMALIZES?

WHAT ARE the benefits of activating the normalization feature?

The “NORMALIZE VOLUME” volume normalization feature allows you to achieve a volume of the same level, music title after music title, regardless of which one succeeds during playback.

How Audio Normalization Works

This provides undeniable listening comfort rather than having to, as before, sometimes turn the volume up or down depending on certain pieces of music.

Note that this difference between a high volume and a low volume sound is called dynamic. If this sound is short or long (1 second or 3 minutes …), be it music, voice or noise.

WHY IS THE SOUND MUSIC OR LETTERS STRONG, SOME TIME?

We must not forget that music, recorded or not, as well as everyday acoustic sounds (those that surround us) are something “alive” which, like during a human discussion, necessarily contains volume passages. weaker sound and others that are louder.

The human ear is by definition used to these differences in sound levels. If these sound differences between the low and high levels did not exist, it could end up giving us a headache because the sound heard would not be natural. The ear needs moments of rest, even if only for a moment, and stronger moments for words to remain audible (and to work the ear again!). The human ear needs this natural “breath”.

Today’s music is very “compressed” (constant sound level, few low levels) when recording (mixing), that is, there are few passages with a big difference between the lowest and highest passage of the song. The STANDARDIZE feature can even be activated and not work much if all the titles of an album are very “compressed”.

Finally, the sound world is like the aquatic world: there are high and low waves. Some tracks are not recorded (mixed) like others. They leave a big difference between low and high noise levels. The NORMALIZE VOLUME feature allows you to level up and try to get everything back to the same level.

WHEN SHOULD I USE THE STANDARDIZATION FUNCTION?

Eg. On the street or in the subway, standardization plays an additional role in making your music more audible. And of course, first and foremost to get a comfortable listening when listening to different music titles with as much sound as possible.

WHY disable the standardization feature?

When the need arises, you can turn this feature off at any time when you want to find this “breathing sound”, titles read (play), with multiple moments that contain smoother (weaker sounds) and higher variations (it’s loud).

Especially if all the titles in your album or playlist are compressed at source, disabling the NORMALIZER feature will help your ear rest, at the end of the day you will be less tired.

Deezer’s NORMALIZE feature does not compress sound and fatigue, it only reduces the major differences between high-level and low-level titles.

Digital audio normalization

In the last decade the term digital audio normalization has become popular. You could say that most people have a vague idea of what they mean. However, it is important to understand some concepts that relate very closely to the issue of the volume gain of an audio file.

One of these issues is audio quality, so we think it is very important to start by explaining what kilobytes per second means.

It is not difficult to understand this concept, however very few people understand it and much less people manage to understand

So let’s try to understand what the subject of kilobytes per second means and how it impacts the quality of an audio file of any format.

This will allow us to have a greater vision to understand the issue of volume, digital audio normalization and loudness given that all this is closely related to audio quality.

So let’s begin to understand why at higher kilobytes per second we will usually have better audio quality.

For this it is necessary to use some examples. But first we need to understand that the greater amount of kilo bytes per second means a greater amount of information per second.

Many will ask And why more information per second synonymous with better audio or video quality?

For that it is important to keep in mind that audio or video files are capturing information and this information is usually very rich in data. For example, the amount of data per second in the performance of a musical group with five or six instruments is quite a lot. Or say the information per second in an image What is very many. So if we lower the number of bytes per second we are reducing the amount of information which impoverish our audio or video file.

The war of volume

For some years now, music recording companies have detected that people listen as a synonym for quality if there is a greater volume And then they have opted for the strategy of increasing the volume of the music they record a little more and produce.

If we had a graphic that will show us the volume and loudness that music used to have in the 70s and we were comparing by decade we could see that the loudness and volume level and volume gain have been increasing decade after decade.

This as I mentioned produces a deceptive effect of perception in the human being that confuses an increase in volume with an increase in audio quality.

And this has been called the war of volume because as we mentioned they have gradually increased the volume level of musical productions to make it appear that they have a higher sound quality.

And how does this compare to bytes per second? As it happens that the amount of information per second does really determine a higher quality and does not need an artificial increase in volume to appear to have a higher quality of digital audio.

So a modern digital audio normalization like the one offered by mp4gain is not misleading, but tries to ensure that each musical passage and each instrument have their optimum volume so that the loudness is constant and so that the quality is the best possible.

Audio normalization

The concern to achieve an adequate sound in the music and a correct balance of the volume levels is something that actually takes centuries.

As soon as the first string quartets or the first symphony orchestras were formed, it was detected that there was a need to maintain an adequate balance of the volumes of each instrument section.
In fact, it is not accidental with a symphony orchestra to have a certain amount of each of the instruments, nor is it accidental that they are accommodated in the way they are accommodated when they are going to play a symphonic concert.

The reason for this is to achieve an adequate balance to the sound of the complete musical piece and it is something that has been thoroughly studied for many centuries.
That is, the human being many years ago of text, what was important to take care of the loudness of each part of a musical piece And of course the global musical work.

Hence we have become accustomed to musical dynamics, What is it that music has more intense moments and softer moments but must be audible all the time, it must be something that is not taken lightly.

Great masters of classical music paid a lot of attention and that is how it was achieved that symphonic orchestras were formed from the amount of instruments that are formed and that were accommodated in a specific way in order to achieve adequate volume management.

This has generated that our ear is used to hearing an adequate musical balance with the correct audio levels and when that is not so we detect that there is a problem and we seek to solve it.

With modern technology and the emergence of digitized music it has been very noticeable for all people that it has become an almost indispensable necessity to normalize the audio.

Normalizing the audio means achieving a standardization where the highest and lowest levels are maintained within a certain standard or certain limits so that it is audible and pleasant for us to listen to all the musical parts that make up a song.

The normalization of the audio has evolved since the music that at first was simply looking for the highest volume peaks was digitized and now in programs such as mp4gain it has achieved very important sophistication that resembles a compression mix, with the use of limiters, and an adequate management of the volume gain of each of the instruments and sounds that form a song.

In other words, we are facing much more modern and advanced algorithms that manage to normalize the audio of music files and videos, even being able to convert from one format to another without problem and normalizing it at the same time. Even The Advance are modern What can perfectly modify the speed of the audio without affecting the Pitch and vice versa.

If you need to achieve the normalization of the audio of a video in the most popular formats of an audio file in the most popular formats the solution is mp4gain which will allow you to easily convert to the format you want and normalize in the most efficient way that exists in the moment your audio or your favorite video.

How does a modern mp3 normalization really work and why is it superior?

Actually we will refer to an audio normalization in general, regardless of the format.

-First attempts to normalize the audio

As soon as the digital format emerged and people were able to store audio files on their computers, it was necessary to encode them to save space, without losing quality.

This is how formats such as mp3 emerged, because they managed to make the same song occupy 10 times less space than a wav format, and if it was well coded and / or with a quality encoder, it sounded practically the same. It was gained in space and the loss of quality was practically zero.

For this it was necessary to maintain a samplerate of at least 44,100 kHz and a bitrate of at least 128.

Initially the most accessible format was the mp3 and although later other formats have emerged (even looseless like FLAC), the mp3 continues to take the place of favorite.

But when a person listens one song after another, he will soon perceive differences in the sonority of these songs. It seems that the volume level is not even, and that is when it becomes necessary to normalize, to avoid having to manually correct the audio volume level of each song by turning the volume knob.

Even Spotify has had to incorporate some normalize option to avoid these annoying volume gain level changes between songs.

The difference is that Spotify only normalizes the volume while playing the songs, so if we stored them on our hard drive, the volumes would remain uneven.

-The solution of volume peaks

The first attempts to normalize the audio of an mp3 were inefficient, they only looked for the peak of a song and amplified it all to the point where those peaks did not distort.

But this did not eliminate the perception that one song would sound louder than others.

Over time the volume level normalization algorithms have been refined and have become more subtle and complex. They have been achieving similar results to those obtained by the great sound consoles in musical concerts, where the music is highly processed to – among other things – make the volume levels are even and unchanged, and also achieve a sussuro of The singer’s voice is audivble even if the battery gives tremendous blows in a roll.

Mp4Gain has come to obtain these results, without the need for you to invest thousands of dollars in hardware like these musical groups or large radio stations do.

Today, audio normalization really is a combination of compression, limiters and normalization, which achieves an amazing result. Far from those first attempts to level the volume gain of each song to avoid big differences.