A good RMS (Root Mean Square) level for audio is one that is loud enough to be engaging but doesn't clip or distort. According to reference material, an optimal RMS level falls between -18 dBFS and -14 dBFS.
Understanding RMS in Audio
RMS, in simple terms, represents the average loudness level of an audio signal. It's a more accurate measure of perceived loudness than peak levels alone because it takes into account the energy of the audio signal over time. Here's why RMS is important:
- Perceived Loudness: RMS is a good indicator of how loud a track will sound to the listener.
- Consistent Levels: Using RMS to balance audio tracks can help create a consistent listening experience.
- Headroom Management: Aiming for a target RMS level helps maintain a healthy amount of headroom, preventing clipping.
- Mixing and Mastering: RMS is a crucial parameter when mixing and mastering to achieve loudness, clarity, and dynamic range in a mix.
Why -18 dBFS to -14 dBFS is a Good Range
The reference suggests an RMS value between -18 dBFS and -14 dBFS, This range serves as a target when adjusting audio levels and offers several benefits:
- Headroom: This range provides enough space (headroom) before the signal starts to clip and introduce distortion.
- Loudness: This range typically results in a loud and engaging sound without being overly aggressive.
- Digital Audio Standard: It aligns with general digital audio practices, providing a good starting point for mixing and mastering.
- Flexibility: You may adjust the gain upwards from this range for loudness (though some limiting or compression may be required) and down as needed for more quiet passages, to create dynamic range.
How to Achieve the Right RMS
Here are some ways to achieve the target RMS range of -18 dBFS to -14 dBFS:
- Gain Staging: Start by setting the levels of individual tracks carefully to avoid clipping or distortion.
- Use a gain meter to check the RMS level of each track.
- Adjust the faders on each track to find a decent initial balance.
- Mixing: In the mixing phase, balance the track levels and use mixing tools such as EQ and compressors to shape the sound, whilst maintaining your target RMS.
- Group tracks into buses if applicable to help manage loudness control.
- Mastering: In the mastering phase, use a loudness meter to target the desired RMS.
- Compressors and limiters can be used to achieve the target RMS level.
In Conclusion
Aiming for an RMS level between -18 dBFS and -14 dBFS is a good practice in audio production for optimal perceived loudness, consistent levels, and a healthy amount of headroom for further processing. Following this guideline will help to ensure a polished and engaging final audio output.
