In the next few posts, we’ll take a look at the various kinds of signal processing done in the digital audio workstation (DAW) to produce a final “mix-down” of the music. A signal flow chart for mixing is available from iZotope, and is shown below.
The signal processing blocks following the solid-state drive (SSD) are concerned with the monitoring/playback process, and have no effect on the recorded audio files. For example, the DAW audio track fader does not affect the amplitude level of the recorded signal. The signal flow in the chart above depicts the flow down the channel strip of a hardware mixing console or the DAW mixing panel. Playback of a track originates from the recording on the SSD. The signal then passes through these basic elements of signal processing and mixing:
Insert Effects: Dynamics and Equalization Processing
Audio Track Fader: Mix Level Control
Pre- and Post-Fader Sends: Time-Based Effects
Audio Track Pan: Stereo Image Processing
Main Output Bus: Stereo Mix
Master Fader: Main Output Level Control
Main Output Bus: Mastering Effects
The final mixed digital stereo signal either leaves the computer and returns to the audio interface unit for playback, or is “bounced” (written) to a formatted audio file, such as a WAV, FLAC, M4A or MP3 file.
The input section and one channel strip of the PreSonus Studio One DAW are shown below.
As described in the preceding post on recording, the input section sends the digital signal waveforms to the SSD, where each waveform is recorded as an individual track. In the example shown above, the “Keyboard R” (right stereo channel of the keyboard) track output from the SSD becomes the input to the DAW channel strip, where the signal processing and mixing will be done. The channel “Inserts” are the first signal processing elements to occur in the signal path chain.
The Equalization (EQ) Insert will be the subject of the next post in this series.