(To read this series from the beginning, start here.)
By now, you’ve used your DAW or stand-alone recorder to record one or more audio tracks, maybe even an entire arrangement with multiple instruments and voices. The next challenge is to transform these tracks into something that can be shared with your fans.
What Is Mixing?
When you are physically in the same room as a group of performers, experiencing their performance, you hear the instruments and/or voices blending together in the room. Depending on the skill of the performers, they will attempt to alter their individual volume and tone such that you hear a wonderful balance between all of those instruments and/or voices.
In the case of multi-track recordings, it is up to the person operating the DAW to manipulate the volume and the tone of each track, such that the blend of all the tracks provides that wonderful balance.
In the pre-computer days of recording, this involved a large mixing desk, plus dedicated devices for manipulating the sound of each track – compressors, limiters, equalizers, etc. Nowadays, it more commonly happens inside the DAW itself, with simulations of those same devices all running as software programs.
The goals of mixing are:
- balancing the tracks
- focusing attention on the significant parts of the arrangement at each moment in the song (to allow the music to tell its story)
- managing the energy of the song through the arrangement and the balance
- helping each track contribute to the song in the way it is intended to contribute
Who Does the Mixing?
It is quite common for separate technicians to perform the jobs of recording and mixing, especially since technological advances have made file sharing so easy. As long as the individual audio files for each track are available for sharing, these files can be transmitted to another technician to be mixed in his/her choice of DAW. Even when the same person is recording and mixing, it is not unusual for that technician to use different DAW’s for recording and mixing.
Where Does The MixDown Go?
In the pre-computer days, all of the tracks would reside on a multi-track tape machine, and the mix of those tracks would be recorded onto a two-track tape machine, in a stereo format compatible with consumer playback systems.
Nowadays, the tracks typically reside as computer files within the DAW, and the mix of those tracks is used to create a stereo audio file on the same computer. Some mixers will still use tape machines for either the multi-tracks or the mixdown, or both, because of the desirable sonic character that a tape machine imparts on its tracks.
A Quick Word About Mastering
There is a subsequent processing step called Mastering. In this processing step, one or more songs (typically a collection of songs) are processed to prepare them for commercial sharing. This will involve adjusting the tone and playback volume of the tracks, and will often employ all of the same devices (compressors, limiters, equalizers, etc.) that are used during mixing, but with a different goal – to create master recordings compatible with commercial playback systems, and compatible with other recordings in the market. This step is usually undertaken by a separate technician, a Mastering Engineer, or even by a mastering program which attempts to make the same mastering decisions as a Mastering Engineer.
Digital Audio Formats
A DAW mixdown file will usually match the format of the tracks within it – that same WAV/AIF format, in 24-bit depth, with 44.1k or higher sample rate. This format isn’t always used for sharing, however, so a version of the mixdown (actually the “master”, as mentioned above) will be prepared in formats more appropriate for sharing – compressed MP3 or AAC formats, for example, and reduced to 16-bit depth. The reason for changing the audio format is generally to reduce the size of the audio file to allow for quick and cheap storage and transmission across the internet. These formats keep much of the fidelity of the original master, but the reduction in size comes with a noticeable sacrifice in the quality of the sound on playback.
The owner of the master recording is advised to always keep the original high-quality WAV/AIF files for future use.
In the next post, we’ll look at how your mixdown must be converted back to an analogue signal to be played back on a speaker system.
Next Instalment: Part Eight – Right Back Where We Started