Distortion at any stage of the audio recording process has been viewed as both essential and intolerable based on what year it is and who you're talking to. Go back to an early rock & roll recording of Little Richard, James Brown or even the Beatles and you’ll hear recordings of artists and engineers pushing the equipment to the edge of their capabilities, adding colouration and tonal artifacts in electrifying ways. Alternately, as digital media became commercially available there was a push for ultimate clarity and definition in audio, leading to advancements in technology and a considerable step back in appeal. Distortion, aka Saturation or Overdrive, in its many forms can also add warmth and oomph to digital audio signals, creating a more pleasant and warm tone by shaping a sound’s characteristics.
Overdrive and distortion comes in different intensities, depending on how ‘HOT’ you set the signal input into the overdrive effect. These can be separated into three general categories:
Used to emulate the saturation that comes from driving tubes in analog gear to the point of breaking up the signal. This overdriven sound is familiar to us as most electric guitar tones playing through an amp and effects pedal or pre-amp will create the grit and bite that makes the electric guitar so exciting! This is the mildest of the three distortions and is used to add bulk to just about any signal and can make vocals, drums, percussion and synths cut through with extra weight. Overdrive also mellows high frequencies and can give your sound a more mellow or vintage sound.
The sound of rock and metal, distortion has a more intense and in your face sound that can be used to toughen up lead lines and add texture to bass. Distortion is created by pushing an amplifier or piece of analog gear even further to the point of clipping, creating an organic buzz on top of your sound or instrument that appear as harmonic overtones. These harmonics can be used to add definition and presence and brighten up a dull or boring sound.
The dirtiest of the three, fuzz offers up a hefty serving of saturation by clipping your sound almost to the point of squaring the waveform and sounds amazing on bass and synths. Fuzz also adds sustain to your sound, naturally adding resonance and stretching out notes with an energizing effect. Be sure to use EQ after fuzz to tame any unwanted harmonics or spiked frequencies.
With any of the above mentioned overdrives, the dynamic range is reduced in a way similar to compression, depending on how much of the effect is applied. With this in mind, overdrive can be used as an additive EQ and mild compression effect by clipping the signal and adding harmonic overtones. By providing all this goodness its no wonder this has been used as a tool since we’ve been recording sound! While this sounds like a one way ticket to awesomeness it’s likely that using it on more than a few instances in any mix will add up to a mess, with all the frequencies and space being used up by the extra texture provided by layer upon layer of saturation. One way around this is to use parallel saturation, as discussed in a later section of this article.
CONTROL THE BEAST
There are many ways to achieve distortion in the real world and inside your DAW, however the controls are basically all the same and can be seen as versions of the following:
DRIVE - Increases the intensity of the distortion from overdrive, to distortion and then to fuzz and beyond. The drive boosts the signal into the effect, which introduces distortion and harmonic overtones.
TONE - The tone control is a simple high-cut filter that’s used to remove any unwanted high frequencies that sound harsh or brittle. Some units also have tone shaping controls in low and mid frequencies to further sculpt the distortion to taste.
MIX/LEVEL - This allows you to blend the overdriven signal with the clean signal or adjust the outgoing level after the overdrive effect is applied.
MIXING WITH DISTORTION AND CLIPPING
At some point during the transition from analog to digital we realized that our music was becoming sterile, clinical and too pristine. In some ways our music had lost the energy and grit that made classic tracks stand out as dance floor anthems. Software manufacturers were quick to realize that our ears are trained to find distortion appealing and started releasing overdrive units to add this character back as a mixing option. Adding distortion to a mix will increase its harmonic density and apparent loudness without adding an increase to the peak level signal, especially when used in parallel on an effects return bus.
Using parallel distortion will allow you to contour the harmonic additions and keep a close eye on emphasized vocal sibilance, increase in treble (especially with percussion instruments) and the masking of mid level frequencies in the mix.
Another popular technique among professionals is to layer overdrive/distortion effects in series so that different textures are provided by different effects plugins, creating a richer and more controllable saturation. Like gain staging, the resulting tone can be created by compiling a number of effects and fine tuned to taste.
The obsession with vintage sounding recordings has brought a wide variety of tape emulation plugins to the market as a way of capturing the old-school production techniques. Tape saturation effects emulate the sound of a recording going to multi-track tape just like it did back in the days of studio recording. Realistically, the entire signal chain was contributing to the saturated sound, from the sound of the pre-amps to the circuits in the console and routing various outboard effects such as analog compressors. I’ve been lucky enough to have experienced this process of recording many times in my life and although it’s not practical or even necessary today, there is a level of excitement and professionalism generated by standing in a row with all of that warm analog gear and the hum of the fans and smell of the transistors all working towards your creative goals…
The sound of legendary multi-track tape devices like the Ampex ATR102 or Studer A800 have been faithfully reproduced by UAD and others, that can offer the tone and saturation of these units without the maintenance and price tag. Simpler plugins are included with most DAWs and can be highly effective in creating the vibe of tape saturation. Either version includes controls for saturation, and even wow and flutter with introduces the speed variances inherent with tape machines and can produce subtle interest in your mix that the listener can barely perceive.
AMP SIMULATION - TURN UP TO ELEVEN