The fight against blaring ads is underway

BarcelonaIt's an all-too-familiar experience: we're engrossed in a movie or TV show when, suddenly, a commercial break starts, so loud that we're forced to quickly grab the remote control to turn it down. This is known as loudness contrast. The National Commission on Markets and Competition (CNMC) has launched a public consultation to determine how to measure loudness levels (loudness, in English) from TV programming and advertisements, in response to recurring complaints about it, to determine whether the networks are engaging in this bad practice.

"I was watching a series at a normal volume, and suddenly the commercial started so loud it woke my toddler up," says one mother. In some surveys, three out of four viewers find the difference in volume between content and advertising "annoying" or "very annoying," and more than half say they've changed channels precisely for that reason. This sound disparity is especially problematic during nighttime hours or in homes with children or the elderly. Furthermore, for individuals with hearing problems or hypersensitivity to sound, the sudden changes can be especially disturbing and even harmful to health.

Why are commercials louder?

The phenomenon has technical and strategic explanations. What we perceive as greater volume is not always a matter of absolute decibels, but of auditory perception and sound compression. Advertising uses a more aggressive dynamic compression, which makes all sounds, from the softest to the loudest, sound at a similar level, creating the sensation of greater volume.

This sound dynamic compression (which has nothing to do with the other compression process, that of images, which is applied because fit With all its resolution within the available broadcast frequency band, it reduces the difference between the softest and loudest sounds and makes all audio—voices, music, effects—sound with greater and constant intensity. While television programs usually present more dynamic variety, alternating quiet moments and silences with more intense ones, commercials tend to maintain a constant and intense sonic presence. For this article, I used a digital sound level meter (for the more technically inclined: with A-weighting, the closest approximation to the human hearing curve; and with Leq value, a kind of average) to measure the levels of different types of programs and stations. The result is clear: the difference between the softest and loudest levels of programs is much more pronounced than that of commercials.

As an example of this difference, during a segment of the program Public mirror On Antena 3, with an average sound level of 59.5 decibels (dB), the minimum level drops to 33.5 dB and the maximum rises to 72.5 dB; however, the minimum sound level for advertisements does not fall below 53 dB. In the case of Let's see Telecinco, with an average of 60.2 dB, a minimum of 36.8 dB and a maximum of 73.8 dB; the minimum level of the advertisements is 52.2 dB. During the Everything moves On TV3, with an average loudness of 58.1 dB, a minimum of 36.5 dB, and a maximum of 72.2 dB, the commercial breaks drop to around 45 dB. The differences may seem small, but it's worth remembering that 3 dB is enough to double the perceived sound level.

It should be noted that these measurements are not representative in absolute terms, because they depend on the volume at which the television is set. A comprehensive study would have to examine how the results vary according to the time slot, the type of program, and between commercials (which come from advertisers and their agencies) and self-promotions (which depend on the same broadcasters). However, it is clear that with relatively similar average, maximum, and minimum levels in the respective programs, A3 raises the minimum for commercials by 19.5 dB, T5 by 15.4 dB, and TV3 by only 8.5 dB.

Either way, it's a strategy to capture attention. When the volume increases, the likelihood of the message reaching the listener also increases, even if they've left the room during the pause.

Live and recorded programs

It should be noted that, within TV programming, the sound dynamics can also be different between programs that are broadcast live (such as one Newscast) and the engravings (like an episode of As if it were yesterday). In the first case, the processing is almost reduced to a limiter to eliminate possible sound peaks, while in the second, homogeneous processing can be applied to the entire program.

In any case, the aforementioned limiting process is applied at several points in the broadcast chain, especially to avoid saturating the link and transmission equipment. In this regard, the phenomenon of loudness contrast can be more noticeable in DTT reception than in live internet viewing of the program itself, because the signal is treated differently in each case.

A curious paradox is that the annoying loudness contrast had become more evident in public television programming, because they tended to be more conservative with the sound levels of their programming, while private television stations already actively practiced auditory stridency in their programs. However, as public broadcasters have adopted practices and content from private broadcasters, this difference is no longer so pronounced.

Regulatory framework and regulations

In 2012, the Catalan Audiovisual Council (CAC) promoted a self-regulation code to avoid sudden changes in sound on television during commercial breaks and program changes. This code was signed by several entities and companies in the Catalan audiovisual sector, including the Catalan Corporation of Audiovisual Media.

At the European level, the Audiovisual Media Services Directive establishes that "television advertising and teleshopping must not unduly emphasize their acoustic power." The European Broadcasting Union (EBU, the same body that manages the Eurovision Song Contest) published recommendation EBU R128 in August 2010, with the aim of standardizing audio levels in broadcasting using loudness meters instead of only peak meters (maximum sound level). The main specification of EBU R128 is to normalize audio to a target loudness level of -23 LUFS (Loudness Units with respect to the Full Scale) with a tolerance of ±0.5 LU. The recommendation contains guidelines for the production, distribution, and reproduction of audio on television, radio, and streaming platforms.

For its part, the CNMC has a public consultation open until the end of this month to address the problem of loudness contrast, in order to specify Article 121.4 of the General Law on Audiovisual Communication, which establishes that "the sound level of audiovisual commercial communications cannot be higher than the average level of the preceding program." This CNMC consultation aims to establish objective criteria to measure and evaluate this obligation, and determine which loudness thresholds should be considered an infringement.

In other countries, EBU Recommendation R128 is already applied mandatory, either directly or in an adapted form. This is what's done in Italy, France, and the United Kingdom. In the US, Congress passed the Commercial Advertising Loudness Mitigation Act (CALM Act) in 2010, but the Federal Communications Commission (FCC) continues to receive complaints about ads that are too loud and is reconsidering its criteria.

Solutions within reach

There are technical solutions to mitigate the volume difference between programs and advertising. On the broadcaster side, the implementation of the EBU R128 recommendation is critical. This involves using appropriate loudness meters during production and transmission to ensure that both programs and advertisements meet the target loudness level. Well-trained sound technicians already know how to avoid the excessive use of compressors or dynamic maximizers.

On the viewer side, many modern televisions and home theater systems incorporate automatic volume leveling features that can help reduce sudden sound fluctuations between different content. These features, which can be activated through the television's audio settings menu—often identified as 'night mode'—dynamically adjust the volume to provide a more consistent listening experience.

On-demand TV platforms are probably the first to have consistently addressed the process of sound dynamic compression, applying, in fact, the same technique as commercial production studios. This, incidentally, also explains why the dialogue in many TV series is more intelligible in the original version than in the dubbed version. It's not that our excellent dubbing actors don't modulate well, but rather that the local dubbing studio compresses the sound dynamics less (or not at all), so it's necessary to turn up the volume to appreciate the faintest nuances.

In any case, one trick to combat the sound contrast is to watch live TV on the internet rather than on DTT; naturally, this is unfeasible for programs where seconds of delay matter, such as sports broadcasts.

Paradoxes of Television Sound

The difference in sound level between television programs and advertisements continues to be a problem that bothers viewers, despite the existence of self-regulation codes and the implementation of the European recommendation EBU R 128. Technical reasons, primarily the use of audio compression in advertising, along with commercial objectives of capturing attention, contribute to this disparity.

One possible solution to avoid the contrast in sound level in TV broadcasts, especially via DTT, would be for broadcasters to give in and follow the example of commercials and also compress the sound dynamics of their programs. In this way, all content would have a similar sound quality, which would avoid the abrupt changes that bother viewers so much. Although this could entail some loss of the programs' rich sound, it would be an acceptable price to pay for a more consistent and comfortable listening experience, especially when listening to programs—and advertisements—with television speakers, which have a very limited capacity to reproduce sound nuances.

Meanwhile, many viewers will continue to reach for the remote to turn down the volume when the commercial starts, in a daily battle for sound control in their homes.