Normalization is an essential process in the world of audio that is used to ensure that audio is played at a consistent volume across different playback systems and devices. By adjusting the overall volume of the audio signal to a specific level, normalization helps to eliminate distractions and background noise, and it can help make the audio more intelligible and easier to understand.
Normalization is often used in the mastering process, which is the final step in preparing an audio recording for release. It can be a powerful tool for improving the overall quality and clarity of the audio.
In this article, we will take a closer look at what audio normalization is and how it can be used to enhance the audio in your projects.
What Is Audio Normalization?
Audio normalization is the process of adjusting the volume of an audio signal so that it reaches the maximum possible level without distorting the audio, while keeping the dynamic range.
One reason this is done is to ensure that the audio is played at a consistent volume across different playback systems and devices or to make the audio more audible by bringing it up to a level that is more easily heard.
There are several different approaches to normalizing audio. The idea is to measure the maximum level of the audio and then adjust the overall volume so that the maximum level is near the maximum possible level without distorting. Normalization can be applied to individual audio tracks or to a final mix of multiple tracks.
It is important to be careful when normalizing audio, as over-normalizing can result in distortion or clipping. It is generally a good idea to leave some headroom when normalizing to allow the audio to be further processed or mastered without causing distortion. Normalization can be done manually but is usually done using a DAW (Digital Audio Workstation).
Why Should You Normalize Audio?
There are several reasons why you might want to normalize audio:
- Consistency: Normalization ensures that the audio is played at a consistent volume across different playback systems and devices. This can be especially important if the audio will be played in various environments or if it will be used in a project that involves multiple audio tracks or elements.
- Clarity: Normalization can improve the audio’s overall clarity and quality by reducing background noise and other distractions. By bringing the volume of the audio up to a more audible level, normalization can help make the audio more intelligible and easier to understand.
- Audibility: If the audio was recorded at a low level or if there are significant differences in volume between different sections of the audio, normalization can help make the audio more audible by bringing it up to a level that is more easily heard.
- Headroom: Normalization can also be used to create headroom for further processing or mastering of the audio. You can avoid distortion or clipping during further processing by leaving some room between the maximum level of the audio and the maximum possible level without distorting.
Normalization can be a useful tool for improving the quality and clarity of audio and for ensuring that the audio is played at a consistent volume across different playback systems and devices.
Normalize Audio in Preparation for Streaming Services
It is generally a good idea to normalize audio before uploading it to a streaming service, as this can help ensure that the audio is played at a consistent volume across different playback systems and devices.
What are the Loudness targets for the most popular streaming services?
The loudness targets for the most popular streaming services can vary. Here are some general guidelines for the loudness targets of some common streaming services:
Spotify: The loudness target for Spotify is -14 LUFS (Loudness Units Full Scale).
Apple Music: The loudness target for Apple Music is -16 LUFS.
YouTube: The loudness target for YouTube is -13 LUFS.
Tidal: The loudness target for Tidal is -14 LUFS.
It is important to note that these are general guidelines and that the specific loudness targets for each streaming service may vary based on the content and genre of the audio. It is always a good idea to check the particular loudness requirements for the streaming service you are using to ensure that your audio meets the required standards.
LUFS (Loudness Units Full Scale) is a measurement of loudness that takes into account the perceived loudness of an audio signal. It is a standardized measure that is used to ensure that audio is played at a consistent volume across different playback systems and devices.
In addition to normalizing the audio, it is also important to ensure that it meets the technical specifications required by the streaming service. This may include requirements for the bit rate, sample rate, and file format of the audio.
What are the Types of Audio Normalization
There are several different types of audio normalization, including:
Peak normalization
Peak normalization is a type of audio normalization that adjusts the volume of an audio signal so that the highest peak in the audio signal reaches a specific level. This can be useful for ensuring that the audio does not distort or clip when played back at a high volume.
Peak normalization analyzes the audio signal in real time and reduces the volume of any peaks that exceed the specified level. The peak can be set to a specific level, such as 0 dB, which is the maximum level that can be represented in a digital audio signal without distorting.
Peak normalization is often used in the mastering process, which is the final step in preparing an audio recording for release. By normalizing the peaks of the audio, the mastering engineer can ensure that the audio will not distort or clip when played back on a variety of different playback systems and devices.
Loudness normalization
Loudness normalization is a type of audio normalization that adjusts the volume of an audio signal so that it meets a specific loudness target. This can be useful for ensuring that audio is played at a consistent volume across different playback systems and devices.
Loudness normalization takes into account the perceived loudness of an audio signal rather than just the peak level or average level of the signal. Loudness is a subjective measure that is based on how the human ear perceives the volume of an audio signal, and it can be influenced by factors such as the frequency content and dynamic range of the signal.
Loudness normalization is typically performed using a tool called a loudness meter, which measures the loudness of the audio signal in real time and adjusts the volume accordingly. The loudness meter can be set to a specific loudness target, such as the loudness targets recommended by streaming services, and the volume of the audio will be adjusted to meet this target.
Loudness normalization is often used in the mastering process, which is the final step in preparing an audio recording for release. By normalizing the loudness of the audio, the mastering engineer can ensure that the audio will be played at a consistent volume across different playback systems and devices.
EBU R 128
EBU R 128 is a standard for loudness normalization that was developed by the European Broadcasting Union (EBU). It specifies a target loudness level of -23 LUFS (Loudness Units Full Scale) for audio that is intended for broadcast or other forms of distribution, and it provides guidelines for measuring and adjusting the loudness of audio to meet this target.
EBU R 128 is designed to ensure that audio is played at a consistent volume across different playback systems and devices. It takes into account the perceived loudness of an audio signal, rather than just the peak level or average level of the signal. Loudness is a subjective measure that is based on how the human ear perceives the volume of an audio signal, and it can be influenced by factors such as the frequency content and dynamic range of the signal.
EBU R 128 is widely used in the broadcast industry, and it has been adopted by many streaming services and other audio distribution platforms as a way to ensure that audio is played at a consistent volume across different devices. It is important to note that EBU R 128 is just one of several standards that are used for loudness normalization, and the specific loudness targets for different platforms may vary.
RMS normalization:
RMS normalization is a type of audio normalization that adjusts the volume of an audio signal based on the root mean square (RMS) level of the signal. The RMS level is a measure of the average energy of the signal, and it is often used as a way to compare the level of different audio signals.
RMS normalization is typically performed using a tool called an RMS meter, which measures the RMS level of the audio signal in real time and adjusts the volume accordingly. The RMS meter can be set to a specific RMS level, and the volume of the audio will be adjusted to meet this target.
RMS normalization is often used to ensure that the audio has a consistent energy level across different sections or tracks. For example, if an album contains a mix of quiet and loud tracks, RMS normalization can be used to bring the quiet tracks up to the same level as the loud tracks, making the album more consistent in terms of volume.
The Dangers of Normalization
There are a few potential dangers or risks associated with normalizing audio:
- Distortion or clipping: If audio is normalized too aggressively, it can result in distortion or clipping, which can degrade the quality and clarity of the audio. Distortion occurs when the volume of the audio exceeds the maximum level that can be represented in a digital audio signal, and it is characterized by a harsh, distorted sound. Clipping occurs when the volume of the audio exceeds the maximum level that can be handled by the playback system, and it is characterized by a flat, truncated sound. Both distortion and clipping can be harmful to the audio and should be avoided.
- Loss of dynamic range: Normalization can also result in a loss of dynamic range or the difference between the loudest and softest parts of the audio. If the dynamic range is too small, the audio may sound “squashed” or lack impact. It is generally a good idea to leave some headroom when normalizing to allow for the audio to maintain some dynamic range.
- Inconsistency: If different audio tracks or elements in a project are normalized to different levels, it can result in inconsistency in the overall volume of the audio. This can be distracting or jarring to the listener and should be avoided.
- It is important to be careful when normalizing audio and to avoid over-normalizing, which can result in distortion, clipping, or a loss of dynamic range. It is generally a good idea to leave some headroom when normalizing to allow for further processing or mastering of the audio without causing these issues.
The Pros Of Audio Normalization
Here are some pros of audio normalization:
- Consistency: Normalization can help ensure that the audio is played at a consistent volume across different playback systems and devices. This can be especially important if the audio will be played in a variety of different environments or if it will be used in a project that involves multiple audio tracks or elements.
- Clarity: Normalization can help improve the overall clarity and quality of the audio by reducing the level of background noise and other distractions. By bringing the volume of the audio up to a more audible level, normalization can help make the audio more intelligible and easier to understand.
- Audibility: If the audio was recorded at a low level or if there are significant differences in volume between different sections of the audio, normalization can help make the audio more audible by bringing it up to a level that is more easily heard.
- Headroom: Normalization can also be used to create headroom for further processing or mastering of the audio. By leaving some room between the maximum level of the audio and the maximum possible level without distorting, you can avoid distortion or clipping during further processing.
Overall, normalization can be a useful tool for improving the quality and clarity of audio and for ensuring that the audio is played at a consistent volume across different playback systems and devices. However, it is important to be careful when normalizing audio and to avoid over-normalizing, which can result in distortion, clipping, or a loss of dynamic range.
When Should I Normalize Audio?
There are several situations in which normalizing audio can be useful:
- When the audio was recorded at a low level: If the audio was recorded at a low level, normalization can help bring it up to a more audible level. This can be especially useful if there are significant differences in volume between different sections of the audio.
- When the audio will be played in a variety of different environments: If the audio will be played in a variety of different environments or on a variety of different playback systems and devices, normalization can help ensure that the audio is played at a consistent volume.
- When the audio will be used in a project that involves multiple audio tracks or elements: If the audio will be used in a project that involves multiple audio tracks or elements, normalization can help ensure that the audio is consistent in terms of volume. This can be especially important if the different tracks or elements were recorded or mixed at different levels.
- When the audio needs to be further processed or mastered: Normalization can also be useful as a starting point for further processing or mastering of the audio. You can avoid distortion or clipping during further processing by normalizing the audio and leaving some headroom.
Overall, normalization can be a useful tool for improving the quality and clarity of audio and for ensuring that the audio is played at a consistent volume across different playback systems and devices. It is important to be careful when normalizing audio and to avoid over-normalizing, which can result in distortion, clipping, or a loss of dynamic range.
When Should I Avoid Normalizing Audio?
There are a few situations in which normalizing audio may not be necessary or may not be the best approach:
- When the audio is going to be sent to a mastering engineer or a mix engineer: Normalizing the tracks will take away all the headroom. The mastering and mix engineers need headroom to work. While it is possible for them to turn it down, this results in a loss of audio quality.
- Normalization can lead to distortion or clipping: If audio is normalized too aggressively, it can result in distortion or clipping, which can degrade the quality and clarity of the audio. Distortion occurs when the volume of the audio exceeds the maximum level that can be represented in a digital audio signal, and it is characterized by a harsh, distorted sound. Clipping occurs when the volume of the audio exceeds the maximum level that can be handled by the playback system, and it is characterized by a flat, truncated sound. Both distortion and clipping can be harmful to the audio and should be avoided.
Overall, it is important to be careful when normalizing audio and to consider the specific goals and needs of the audio project. Normalization can be a useful tool for improving the quality and clarity of audio and for ensuring that the audio is played at a consistent volume across different playback systems and devices.
However, it is important to consider the specific goals and needs of the audio project and to avoid over-normalizing, which can result in distortion, clipping, or a loss of dynamic range. In some situations, normalization may not be necessary or may not be the best approach, and it is important to consider other options for improving the quality and clarity of the audio.
What’s The Difference Between Normalization And Compression?
Normalization and compression are two different techniques that can be used to adjust the volume of an audio signal. Here are some key differences between normalization and compression:
- Normalization adjusts the overall volume of the audio signal to a specific level, while compression adjusts the dynamic range or the difference between the loudest and softest parts of the audio.
- Normalization is typically used to ensure that the audio is played at a consistent volume across different playback systems and devices, while compression is often used to control the volume of specific parts of the audio or to create a particular sound.
- Normalization is typically performed using a tool like a level meter or a peak limiter, while compression is typically performed using a compressor, which is a type of processor that adjusts the volume of the audio based on a threshold and a ratio.
- Normalization is generally a one-time process that is performed on the final mix of the audio, while compression is often applied in multiple stages and can be used on individual tracks or elements in addition to the final mix.
Overall, normalization and compression are two different techniques that can be used to adjust the volume of an audio signal, and they are often used in combination to achieve specific goals or create particular effects. It is important to understand the differences between normalization and compression and to use the appropriate technique for the specific needs of the audio project.
Gain staging Vs. Normalization
Gain staging and normalization are two different techniques that can be used to adjust the volume of an audio signal. Gain staging refers to the process of adjusting the gain, or the volume, of each stage in a signal chain to an optimal level. This can be done using the gain controls on individual pieces of equipment or in software during recording, mixing, or mastering. The goal of gain staging is to maintain a healthy signal level throughout the entire signal chain and to avoid distortion or clipping.
On the other hand, normalization adjusts the audio signal’s overall volume to a specific level, typically using a tool like a level meter or a peak limiter. Normalization is often used to ensure that the audio is played at a consistent volume across different playback systems and devices. It can be a powerful tool for improving the overall quality and clarity of the audio.
Gain staging is often the more flexible and nuanced approach to adjusting the volume of an audio signal, as it allows you to control the volume at each stage of the signal chain and to make more precise adjustments. Normalization is a more global approach that adjusts the overall volume of the audio signal to a specific level, and it may not be as fine-tuned as gain staging.
How To Normalize Audio
One tool that can be used to normalize a track is Audacity. It has options for Loudness normalization and RMS normalization. I created a step-by-step guide that you can read here: What Does Loudness Normalization Do In Audacity
You’ll find the steps toward the end of the article, along with an explanation of what the options do.
Instructions for how to use it can also be found on their help page here: Audacity Loudness Normalization.
If you’re interested in learning what else Audacity can do, check out this article on using Audacity as a DAW.
Here are some videos that I found helpful: