Mixing Part B
Music mixing is akin to moving into a new house or apartment. Your furniture and belongings represent all the individual performances that you have recorded in a song. Your job is to situate those performances in a manner much like you would the furniture you are moving to your new home. If done right, it is something that you can enjoy for years to come. Whether the results are good or not depends on the decisions you make along the way.
Because every song is unique it will require creative decisions that are impossible to formulate. I can't tell you what color to use on the walls, where to place the furniture in the room, what types of shades or blinds you use on your windows. These are creative choices, you have to make based on the layout and square footage of the house. What I do hope to accomplish here is to give you a fundamental process that underlies every decision you make. This way, every decision you make will come from a fundamentally sound place.
To carry the moving analogy further, let's look at the fundamental process of music mixing. There are many things in this process that are subject to interpretation. If you want to open all the boxes with a sawzall, that's up to you. The beauty of mixing is that , unlike moving, at least you can always hit the undo button if you butcher something! The process laid out here is not entirely a linear way of working through a mix. You may find that you have to take steps back in this process quite often in order to find you way to a great mix. When you step back to make changes, continue to follow the outlined steps in order.
The Fundamental Music Mixing Process
Levels And Panning
Subtractive Eq And Editing
Printing The Final Mix
Lets dive right in with the first step in the music mixing process.
Moving In (Levels and Panning)
Imagine yourself moving into a new house. You bring in furniture, loads of boxes full of clothing, books, pots and pans, etc… You then go about the process of unpacking all of your boxes, taking the packing blankets off of your furniture and starting to organize your belongings. Boxes marked Kitchen will go into the kitchen. Boxes marked bedroom go to the bedroom. Boxes marked office, go into the office, etc… Move tracks that work together in your mix next to each. This will keep you from moving around too much in your mix window.
Imagine now that each box and piece of furniture is an audio recording that is part of your mix. The elements of your song that run throughout, drums, bass, guitars, and vocals are the furniture. The added tracks that fill out the rest of the recording are the pots and pans, lamps, books, paintings etc…
This is the Level and Panning phase of the music mixing process. You should carefully place sounds, like your furniture, in a way that is complimentary to the song. If the focus of a room is the TV, then all of the furniture in that space should be pointing towards the TV and arranged in such a way that you can enjoy watching it.
The mindset of levels and panning has to do with the relative distance (levels) and the placement in the room (panning) to the TV. If the TV represents the lead vocal in your mix, the same care should be taken to make sure the other instruments compliment the placement of the lead vocal. If they get in the way, the attention to the vocal will be lost.
Start with the big stuff first and move it into place. There is a reason that most engineers start with Drums and Bass first before moving on to other instruments. Even engineer's that start with the vocals first (a top down mix) usually go straight to drums and bass after getting a vocal sound.
Take Out the Garbage (Subtractive EQ and Editing)
Once you have finished unpacking and placing your furniture you will be left with piles of empty boxes and packing materials that no longer serve a purpose. You may even realize that you have extra stuff you don't really need anymore. This will become evident as you continue the process.
The idea here is to strip away what is not necessary from the audio tracks. This includes, but is not limited to, filtering off low frequency rumble or hiss, eliminating or muting performances that don't work or cloud the production, applying subtractive EQ to recordings that are muddy of indistinct and editing out areas of regions where no music is present.
This phase of music mixing process yields enormous benefits. It allows you to better enjoy the details of the individual performances. By removing the clutter, space will be created that gives you the flexibility and room to shape the sounds any way you like.
After using applying this process, adjust levels to compensate for the changes that you have made. This is critical because removing the garbage from your tracks will mean that other tracks are less covered up and may be louder in the mix. The tracks you apply subtractive EQ to may also sound lower in the mix and need to be raised.
Packing It In (Compression)
There is no perfect analogy of compression to the move into your new house. Compression directly affects the perceived size and density of a sound. The closest analogy I can give is based on how much furniture you have, and how big all of it is. The more furniture, the more closely packed each piece may need to be placed. You may also decide to put a smaller couch in the TV room if that is what the room allows.
Compression is by far the most misunderstood form of processing for the novice or inexperienced professional in the music mixing process. The fact that it is difficult to hear for most has to do with the fact that most don't really know what to listen for. If you look at what compressors do in our everyday world though, the picture should be a little clearer.
In general, compressors make things smaller and more dense. Pressing on the cap of a can of compressed air will show you the effects of compression. If you apply this same principle to audio, the track you apply the compression to will also become smaller and more dense. The sound emanating from the speaker will also be projected more forcefully similar to the way the compressed air escapes the can.
Compressors can serve many different purposes when music mixing and it's very important to know what these basic uses are and when you need them. Never apply compression to a sound unless it serves a specific purpose. If you don't achieve the desired effect you are looking for, leave it out.
The Primary Functions Of A Compressor Are As Follows:
Even Out A Performance
Add Presence To A Performance
Control The Perceived Sustain And Groove Of A Performance
Add Aggressiveness To A Performance
Shrink The Size Of A Performance
All of these forms of compression have very specific purposes in music mixing. They allow the sound to moved around in the speakers mostly front to back but also up and down if used within specific frequency areas. After the subtractive EQ is done, compression can serve many of the purposes additive EQ will serve in a mix but with an added benefit. EQ adds volume to given frequency areas, compressors add density. One makes the track bigger, the other more dense and powerful.
Compression, like any other form of processing, requires that you zoom your attention out to the whole mix and adjust levels after processing. Notice how the adjustments you have made affect the other tracks in the mix. The fundamental idea here is to always make sure all the individual performances are working together in a mix.
Size Matters (Effects Processing)
The size of your mix is defined by reverbs and effects processing in the music mixing process. To carry this out through the moving analogy, the larger the house, the bigger the furniture that goes into it can be. Most confuse size with frequencies, particularly with the amount to low end. This could not be further from the truth. Size is a function of the perceived 3 dimensional space, EQ is primarily a 2 dimensional tool.
Like the bigger house, the size of the space you select determines how big you can make the individual performances in your mix. Another common misconception is that the size of a space is determined by reverb time. Actually, it's determined by the amount of pre-delay.
Think about what size space is appropriate for the type of music you are mixing. Classical music does not generally sound great when placed in a small space. A punk rock record will be a huge mess if placed in a very large reverent space. These decisions are mostly based on the musical style of the song. An aggressive song generally needs to be dryer in order for it to sound "in your face". A slower song requires more reverb and effects to fill in the empty space.
The Benefit Of Effects Processing Before Additive EQ
Unless there are any pressing needs for additive EQ I usually like to add effects before shaping frequencies. The use of reverbs, delays and modulation effects like flanging in music mixing can usually do more to help get the sound you are looking for. Effects processors add Tone to a sound, not EQ. They also allow you to separate instruments by helping to create a 3 dimensional space in the speakers. When used properly, you can get a lot of perceived size out of your mix without overloading frequency areas in the mix.
Let's take a quick look at some examples:
1. Tone: The tone of a harsh bright vocal can rarely be satisfactorily fixed with EQ. Using a very short, warm sounding, reverb or early reflections program will instantly add body to the voice. Throw a longer warm reverb like a hall program on top and you will have accomplished the majority of the warming you want without losing the presence of the voice. The same concept can be applied to a dull sounding voice by using a bright reverb to add presence.
2. Space: Short room programs are a great way to add depth and space to a sound. How close the dry original sound is depends on the amount of pre-delay. Pre-delay is the amount of time before the onset of reverb. The longer the delay, the larger the perceived space. The wet dry balance determines how far back in the speakers the dry sound is from you when using a reverb with no pre-delay. Using longer pre-delays will make the reverb sink back behind the speakers.
3. Spread: A chorus effect panned in stereo will widen and thin out a sound that is too dense. It can also spread a sound outside of the speakers to the left and right by panning the dry signal to one side and the mono chorus effect to the other. The modulation effect can be hidden by minimizing the depth and speed of the chorus.
Effects processing can also be used to group instruments together or separate them from each other. Using the same short room program on all the rhythm section instruments is a great way to make them sound like they are performing together. Using a unique effect for the vocal, that no other instrument shares, will make it stand out from the other vocals and instruments. Always adjust levels after adding effects.