.jpg)
Mixing can sometimes feel like a daunting task. What is the loudest point? How do I ensure all the dialogue is audible amongst the FX and Music? How do I keep intensity without your ears getting tired? How do I ensure a quiet moment is actually audible? And all at the same time!
While there are industry standards for overall loudness, the modern trend of pushing the loudness of film has highlighted how, within these standards, the guiding hand of direction and personal taste can result in drastically different outcomes for the viewer. Especially when taking into account different media, genres, and stylistic choices. What is the right balance, and how can you strike it?
In this article, we’ll answer all those questions, and get you balancing your SFX with more confidence – whether you make them fresh and unique yourself in Krotos Studio, or get them elsewhere.
To an extent, the exact answer does depend on your format (video, film, TV, games…), the context (tense scenes vs action scenes…), and on the genre you’re in (horror, sports, period…). But as a rule of thumb, your music should be approximately -20dB, while sound effects should be louder, sitting between the same -20dB level (footsteps, environmental sounds) and -10dB (hits, cracks and louder sounds), with real peaks getting even louder. Remember, there is scope for varying these levels when appropriate to your context, so use your judgment in addition to this general guidance.
There’s no easy or strict answer to this question, as the relative levels of music and sound effects can vary, and are dictated by a number of factors. Mixing is as much an art as it is a science, so knowing what style you are trying to achieve (and doing so with confidence) is as important as knowing the numerical values you are aiming for.
That being said, there are industry standards for a reason, and you must understand them first before you bring forth your vision. You wouldn’t want to accidentally blow up a speaker or leave your audience cupping their ears to better hear what’s being said.
A common loudness measurement you may run into is called LUFS (Loudness Units Full Scale). While we won’t go too deep into LUFS (which measures perceived loudness, unlike dBs), we’ll tell you that there are standards for LUFS volume levels for TV, Film, and other formats. For example, music generally is mixed and mastered to around -14 LUFS, while TV audio sits at -23 LUFS, and film at -27 LUFS. However, these ‘standards’ aren’t universal, and each project will have its own required overall integrated LUFS and guidelines for music/SFX levels (so make sure to ask for a written outline for deliverables).
As a general rule, music is more of a support to the narrative and therefore is generally quieter than the dialogue and SFX, particularly when alongside dialogue and sound. Going by general industry practices, as seen in the Sundance Film Festival's 2023 Specifications, a film should be mixed to -24 dB LUFS overall (sometimes referred to as integrated LUFS).
Since dialogue takes up the majority of the mix, this would mean that in moments where there is no talking, the music has space to be louder (if applicable for the scene), with the volume decreasing in moments with dialogue or louder sound elements. Finding the level depends on the style of music and taste, alongside the usual mixing rigmarole of not having too much of a certain frequency taking up the mix to avoid mud.
SFX tends to be secondary to dialogue within the sound mix, as it enhances the realism of a scene and creates an atmospheric foundation for the dialogue. Key story elements are often conveyed through sound, sometimes telling as much of the narrative as dialogue. Therefore, the balance between dialogue and sound design is very important and often depends on the style.
If you are shooting for naturalistic realism, then sound FX will often be more reserved; if you are working on an action movie, then it can be important for sounds to have an exaggerated impact and weight in the mix. Balancing sound and music can be a tightrope walk, especially if you’re dealing with a sequence that’s more music-driven anyway. The music overtaking the sound can give a sense of weightlessness, which is great for gentle moments or at the peak of a scene's crescendo.
As previously mentioned, the balance between your SFX, Music, and Dialogue changes depending on what role they are fulfilling. In this section, we will briefly outline some of the reasons why.
Sound and music will intrinsically play a different role in different formats. In video games, dialogue is usually kept to cutscenes or NPC interactions, so the music and the SFX are doing more within the sound mix. Sound design, in particular, plays a massive part in giving the players' actions weight and is therefore quite loud in the mix.
TV, unlike film, is mixed primarily for home viewing and is very dialogue-heavy with less sound design (although with TV becoming increasingly more cinematic the difference in mixing is getting less and less). Audiobooks and radio plays will keep sound design and music at a quieter level throughout, as the dialogue/overall levels need to remain very consistent.
Consider an action-packed sports scene, with panicked footsteps, heavy kicks and net sounds, compared to a tense horror scene, with creeping sounds and sudden snaps. Both are using sound for a different effect. This is more obvious in genre films where sound and music are integral parts to the film's character (think John Carpenter synth scores and exaggerated gore sounds).
This is the same across different formats; realistic action games sound very different from cartoonish adventure games. Even movies that are shooting for out-and-out realism are a result of mixing and balancing the SFX in such a way as not to bring attention to their artifice, and in doing so are equally as stylized as an ’80s horror.
Balancing Sound Effects and Music Based on Context
Sometimes, even though a film is aiming for realism, there will be moments where sound and music take the lead storytelling role, becoming more impressionistic and non-diegetic. It could be a dream sequence, a drug trip, a moment of horror, or a memory replaying in a character's head. What sets these scenes apart is that they break away from the established reality of the film, with dialogue perhaps becoming muddled amongst a wash of sound and music.
Of course, there are many narrative reasons to play with sound like this. Sometimes it may not be during an obvious sequence, but making the sound unusually quiet, focusing on an odd sonic detail, or introducing music where there usually wouldn’t be can create a unique effect.
Even with access to a top-of-the-line studio, certain pitfalls of mixing can drastically affect the experience for the viewer when playback isn’t taken into account. The balance between music, dialogue, and SFX is even subject to change when experienced on different playback systems, and focusing too much on one type can lessen the impact when experienced on others.
Some blockbuster movies have been known to ignore the range of home listening systems commonly used, leading to complaints of the sound effects and music being too loud and the dialogue being too quiet (such as Christopher Nolan’s TENET). In the age of the iPhone and social media, it is also imperative that phone speakers and common headphones/earbuds also be tested, as it’s likely that this is the medium your project will be most experienced.
It’s common for higher-budgeted projects to have multiple mixdowns for different contexts (IE, a multichannel mixdown for theatre showings, and a stereo for home viewing/streaming); however, there isn’t always time or budget for two dedicated separate mixes – let alone the multiple iterations needed to test the plethora of other possible playback systems.
Therefore, we recommend that you have reference speakers of various varieties that you can bounce between to check where possible (for example, a lot of post studios nowadays have sound bars and TVs to check mixes through). Doing this in tandem with a multichannel-to-stereo downmixer, such as the Nugen Audio Halo Downmixer, can allow you to test on the fly and maximize compatibility.