“Loudness War” (The Battle for Volume)

What Is the Loudness War?

It is a trend that began in the 1990s, when music producers and audio engineers started to increase the perceived loudness of tracks more and more by dynamically compressing the audio signal.

There are mainly two reasons:

• Louder tracks attract more attention, especially on radio or in playlists.
• It was thought that a “louder” track—that is, one that at the same playback volume setting “sounds louder”—would sell more or be liked more (which is not always true).

How Does It Work Technically?

On any medium, whether analog or digital, sound is stored as an electrical signal that varies between a minimum and a maximum value. The central reference point is zero, which represents the absence of signal, while the effective value of these variations is indicated as V_RMS (root mean square value).

The interval between the minimum and maximum values—that is, how much the signal can vary—defines the dynamic range of the signal, meaning the ability of the sound to move from very quiet passages to very intense ones.

When we use compressors or limiters to reduce the upper excursions of the signal (that is, the peaks), we obtain a sound that seems louder when heard. This happens because we increase the average level (V_RMS), while at the same time reducing the actual dynamic range: the signal occupies a narrower portion of its possible excursion.

This phenomenon is technically described by the crest factor, which represents the ratio, expressed in decibels (dB), between the signal’s maximum peak (its maximum amplitude, measured in volts) and its V_RMS value.

A signal with a high crest factor retains good dynamics and detail, while a lower crest factor indicates a more compressed and less articulate sound.

What Is Happening Today?

Fortunately, the Loudness War is slowing down somewhat: many platforms (Spotify, YouTube, Apple Music…) normalize loudness, so heavily compressed tracks no longer sound “louder” than others.

This has led some producers to return to greater dynamic range in pursuit of better sound quality.

Vinyl = Dynamics? Not Always…

By its physical nature, vinyl cannot support the extreme levels of compression typical of digital files or CDs. However, many modern vinyl records are pressed from the same compressed digital masters used for CDs or for streaming on platforms such as Spotify.

This means that, if we expect a more dynamic sound simply because we are listening to vinyl, we may be disappointed: the medium is analog, but the content may be identical to that of compressed digital formats.

There is, however, another option: look for vinyl releases made from original analog masters, often labeled “audiophile”. These high-quality editions often state “From the original analog tapes” on the cover, indicating that the content has not been digitally compressed.

Another alternative is to buy original vinyl records from the 1970s and 1980s, made before the so-called “Loudness War” began. At that time, the dynamics of recordings were preserved and mastering processes were not yet dominated by the pursuit of loudness at all costs.

In conclusion, beware of “modern traps”: even on vinyl, the sound can be compressed if the source is a digital master optimized for loudness rather than quality.

How Can You Measure the Dynamics of a Digital Track?

First, it is necessary to obtain the signal in digital form. If the source is digital (such as a CD), it is important to use software that guarantees a bit-perfect extraction, meaning that the original data are not altered in any way.

One of the most reliable programs for this purpose is Exact Audio Copy (EAC), which can extract audio from a CD with exact bit-for-bit accuracy, saving the files in WAV or FLAC format.

Once the digital audio file has been obtained, we can analyze its crest factor using software such as Audacity, following these steps:

1. Open the track in Audacity.
2. Go to “Effect” → “Amplify” and note the detected peak value (expressed in dB).
3. Then use “Statistics” or a plugin such as “ReplayGain” to estimate the RMS value (also in dB).
4. Calculate the difference between the peak value and the RMS value:
   Peak – RMS = Crest factor.

A high crest factor indicates greater dynamic range (peaks farther from the average level), while a low value indicates signal compression and therefore reduced dynamics.

An Example

Let us examine an MP3 track with Audacity: we load it into the program and measure the maximum peak value:

The maximum peak value is therefore +1.139 dB:

We measure the RMS value of the signal using the Nyquist plugin, which is installed by default:

the value:

we can use -9.163 dB, and therefore calculate the crest factor:

Crest factor (dB) = Maximum peak−RMS = 1.139−(−9.163) = 10.302 dB

Subtraction is used because crest factor, expressed in decibels (dB), represents the ratio between the peak value and the RMS value in volts. Since the values are already expressed in dB, the ratio is calculated by subtraction: Peak dB − RMS dB. This gives the crest factor directly in decibels, without having to convert the values to volts.

If we want the linear crest factor, we calculate:

therefore, the linear crest factor in this example is ≈ 3.27

Crest Factor Calculation

Further Reading

“The Loudness War: Background, Speculation and Recommendations“ by Earl Vickers (2010): This article examines the history of the Loudness War, its possible consequences—including aesthetic concerns and listener fatigue—and provides practical recommendations for de-escalation.

“The Loudness War & Hypercompression: Quantifying the perception of compression effects“ by Andreas Juwan: This study uses listening tests to quantify the perception of dynamic compression effects, contributing to strategies aimed at ending the Loudness War.

“The Loudness War: Do Louder, Hypercompressed Recordings Sell Better?“ by Earl Vickers (2011): This article questions the assumption that louder, hypercompressed recordings sell better, presenting evidence that loudness is not significantly correlated with listener preference or sales rankings.

“Imperfect sound forever: loudness wars, listening formations and the history of sound reproduction” by Kyle Devine (2013): This article explores the loudness wars in the context of listening formations and the history of sound reproduction.

“The Loudness Wars“ by USC Viterbi School of Engineering: This article discusses the impact of the Loudness War on sound quality and listener perception, highlighting how excessive compression can degrade the quality of music recordings.