My music production tracking workflow is what I consider to be a hybrid affair. Half of what I track in Pro Tools is audio by use of microphones and preamps, the other half is dominated by virtual instruments triggered by MIDI performances. I'm sure a vast majority of you reading this article produce music the same way, after all, it is the 21st century.
I often come across some universal issues with virtual instruments that I want to highlight in this article. What really bugs me about Virtual Instruments are the hotter than hell output levels they produce right out of the box. I'm not going to point my finger at any particular Virtual Instrument or developer as I feel this is an issue with many, not all, virtual instruments on the market. may it be a soft synth, keyboard instrument or drum library. I'm going to refer to this problem as "The Virtual Instrument Loudness Wars In DAWs". I find I am constantly battling with levels of virtual instrument tracks when I record audio. I also find that I punish my poor master track fader at early doors of most VI heavy productions.
Why are virtual instruments so loud? Why don't virtual instrument developers give us some headroom?
Before I dive any deeper into my virtual instrument rant I want to quickly cover the bare-bone basics of getting a safe audio signal into DAWs.
DAW Audio Tracking Routine vs VI Tracking
We all know that we don't need to get audio input signals anywhere near the red line in the digital domain, but for those inexperienced guys that don't know, I'll quickly explain why...
In the analog tape days, it didn't hurt to drive the input past what today we consider to be a safe point. If we pushed the input close or into the red "to tape" we got pleasing saturated characteristics. In the digital domain, this does not happen. We get digital clipping which sounds horrible. There are several other reasons why it's pointless to get audio input levels in DAWs close to clipping... but we'll save that for another article.
The best practice for setting a safe audio recording input level within a digital audio workstation is to aim for the loudest part of a performance to hit no higher than roughly two-thirds up the meter. This gives us "headroom" which is essential for avoiding clipping if a louder moment of a performance does occur in tracking. Headroom also gives us space to work with plug-ins later in production as some plug-ins can add extra volume.
An Example Of The Virtual Instrument Loudness Wars In DAWs
Now that we fully appreciate why it is important to record audio with suitable headroom let's move across to how the audio tracking workflow doesn't always work alongside virtual instrument tracks.
Let's say I've loaded a drum library on an instrument track and MIDI is triggering a groove. The output from the drum instrument is hot, clearly, as the loudest peak on the track's meter is only a hairs width below clipping, but it doesn't go into the red. If I leave this be and move along to recording bass and acoustic guitars audio tracks I find I start to get into monitoring problems because the volume of the drum VI is incredibly high. I can hear the loud VI drums but not a lot of the bass guitar track that I'm about to record. I can pull down the drums VI fader in the mix window down or turn up the bass but my master track may start clipping.
The only way around this is to turn down the master output level within the Virtual Instrument/Library UI, which works. When I turn down the output within the UI, all of a sudden I give myself valuable headroom similar to what I have on my audio tracks. Here in lies the source of today's rant - Why, in many VI cases, is headroom so limited within virtual instrument? Am I the only person producing music that gets frustrated by this gain staging dance between VIs and audio tracks?
There is also another virtual instrument problem I often come across...
Virtual Instruments Can Be Easy To Clip Internally
Many virtual instruments and libraries, such as drum libraries, feature internal mixers and effects/dynamic processors. Push a fader slightly up on a kick or snare fader within a drum VI and the output of the VI clips. Add some effects within some synth VIs and again clipping occurs.
Headroom Is The Answer
When gain staging issues occur headroom is always the answer.
If audio tracks clip in a recording stage we turn down at the preamp, if a VI sounds clipped or distorted we turn down the VI master output level, when plug-ins sound punished we turn down the input/output gain levels... simple right?
Yes, gain staging is a simple, and necessary. it just feels as though gain staging techniques are more challenging than they have to be because virtual instruments are typically hot out of the box.