We know the ‘loudness wars’ is a constantly hot topic in music production circles and one common belief is that a loud master is produced in the mastering stage. Certainly mastering can increase the perceived volume of a mix down. However there is often a limitation to how loud a mix can get before it starts to produce undesirable side effects such as distortion, loss of detail, loss of dynamics etc. I am occasionally asked how you can produce loud mixes and I would in the very first instance suggest mixing to sound good and not just loud. People should also consider the genre they are working in, the needs for a drum and bass/dubstep track are very different for a folk or ambient piece so be sensitive to the musical genre within which you are working. Also consider that software like iTune Soundcheck is also making “loudness” somewhat less relevant as it tries to even out perceived volumes of tracks in the playback domain.
People are going to remember quality and not the loudness of your musical tracks. So quality is the goal, not loudness, however in saying this it is possible to draw a compromise and retain quality and yet build some loudness into your work at the mixing stage. We are going to discuss some of the reasons why some music sounds loud and also how you can mix to achieve this if so desired. The techniques focus on the multi tracks/ DAW tracks and not the master bus.
It is important to understand that our ears perception of what is loud is complex and relates to both the duration of a sound and spectral content. Fast transients are not perceived as being as loud as sounds that have the same spectral content and level as those that have a longer duration. Additionally the ear is sensitive to the contrasts of higher and lower amplitude signals, this creates a reference from which something can be deemed louder to the ear and brain.
A song can contain micro dynamics which are short duration level changes and also macro dynamics, for example the changes in level between verses and the chorus of a song and how a sound dynamically progresses across the entire piece of music, so there is a lot to consider.
Do not underestimate the importance of the initial choice of sounds in your mix, the spectral content of the sound sources will go some way to determine their perceived volumes when mixed together, it is a complex interplay and you can bear it in mind when selecting sources. I do not recommend choosing sources based on the fact they have a relatively high perceived volume as it goes against the artistic principles of choosing pleasing musical instruments that augment the musical message. But it can certainly be considered and is useful to know the harmonic structure of sounds can have a bearing on the perceived volume of a mix.
General mixing techniques for increasing the perceived volume of tracks will include equalization (we all know the ear is more sensitive to the mid range frequencies than the extreme highs and lows) so this can be used with great care to gentle push the sounds “loud” spectral content. However it must always be done with taste in mind as a mix element can easily become harsh if unnatural EQ boosts are applied. You can also filter out the deep lows which can eat headroom (usually sub 35Hz) and allow the rest of the spectrum to be pushed slightly higher if required. A good check to ensure the eq is not getting too harsh is to get your monitoring level up at 85dB SPL. If you start wincing when the guitars come in or the vocal starts it’s safe to say that you boosted the mids a little too much. It’s a fine line between louder and aggravating.
Dynamic range control such as compression is a very useful tool in music which can add some drive to a sound source. As well as being practically useful in being able to keep a sound consistent (refer to sound duration above) it can give the track a sense of intensity when used well. It is however easy to over compress and then need to follow suit with other sources to get all mix elements up front. It is easy for a novice mixer to over compress and end up with a blanket wall of sound that loses nuance, detail and natural dynamics so do not over do it.
Gentle distortion can also bring a perception of loudness, as a rule distortion tends to make the upper harmonics more audible and this distortion is often at the frequency range where the ear is most sensitive. There are many ways to apply distortion to an audio signal in a typical digital audio workstation, tube emulation, audio transformers (analog or emulated), harmonic exciters, analog equipment emulation, and tape saturation type effects. These processes are to be used with care as again you can end up with a harsh and fuzzy end result that lacks fidelity and detail.
Final limiting of music is a useful way to bring the volume up a little in a fairly transparent way. It is useful to ensure you can level match the before and after results to be able to hear the detrimental affects of the limiting action. Listen out for drum transients being rounded off and unnatural peak compression on vocals, if they are prominent in your track. I find that beyond a certain level of limiting a track becomes strained, stifled and mushy so keep checking to make sure you have drawn a good compromise for you music.
To sum up these are all viable techniques to creating a louder mix down but they require a considered approach in order to balance the positive attributes of increased level versus the downsides of noticeable distortion, loss of space, depth, detail and a sonic blanket of sound people will with to turn down.
Strive for fidelity and quality first and loudness second but in any event these techniques can get you a long way to making a louder mix.
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