A guitar covers about 3.5 octaves, a bass about 3 octaves, most voices do a few octaves—but keyboards can cover 7 octaves and beyond. What’s more, synthetic sounds often cover a huge part of the frequency spectrum (second only to drums), from thundering bass to trebly highs. Your mission, should you decide to accept it, is to get that monster sound to play well with other instruments, and sit in a mix instead of dominate it (unless, of course, the keyboard is supposed to dominate the mix!).
The Electric/Acoustic Dichotomy
If you’re recording primarily acoustic instruments, or electric instruments through amps, mixing in a synthesizer that was recorded direct will often sound just plain “wrong”—it will lack the “air” created by recording acoustic instruments through a mic, as well as have an extended high frequency response compared to acoustic instruments.
There are four main solutions, which can be used individually or together:
• Roll off some of highs. A little highfrequency shelving, down maybe 1.5dB starting at 10kHz, will bring the high-frequency spectrum more into line with acoustic instruments. Be careful, though; don’t dull the sound too much, as it may still have to balance sonically with the high frequency transients caused by, for example, picking an acoustic guitar string.
• Feed the keyboard through an amp, mic it and record it to a track, then blend that with the direct track. If well-recorded, you might even want to use the amp sound by itself. A PA, or portable PA/instrument amp like a Bose L1, can give a neutral sound while a guitar amp offers more “character.”
• Play back the direct recorded sound through your monitors, and mic them. This is a variation on going through an amp, but if you don’t really have any other way to add ambience, this will work in a pinch.
• Add multiple short delays (around 15–30ms), and mix them in at low volume with the direct sound. This helps simulate the sound of getting early reflections in a room. A tapped delay with eight or more taps is ideal for this; too few taps probably won’t give a realistic enough sound.
The Potential of Proper Panning
Most current synthesizers have stereo outs to take advantage of any onboard stereo effects, as well as provide panning options. For example, some patches might tie notes to panning so that the left notes come out of the left speaker, and the right notes come out of the right speaker; or splits might be placed in stereo.
However, few instruments other than drums are stereo. Guitar, bass, woodwinds, voice, and the like are basically mono sources, with stereo created through the use of ambience (real or artificial). If the keyboard covers the entire stereo field, that doesn’t leave much room for other instruments.
Figure 1 shows a typical rock band panning scenario. The stereo synth pans from left to somewhat left of center rather than full left to full right, and the stereo rhythm guitar pans from right to somewhat right of center. The center is left open for bass, kick, vocals, leads, and other “center-oriented” parts, while the drums can be panned across the stereo field, along with “extras” like percussion or delays.
To spread the synth as desired, simply pan the left track full left, and the right track to left of center (if the DAW’s track contains a stereo signal, you may need to split the stereo track into two mono tracks so each can be panned individually, or there may be some kind of balance control that does the job). Sonar users can take advantage of the Channel Tools plug-in (Figure 2), which allows changing not just the angle of each channel in a stereo track, but also the width. For example, the keyboard could spread in “stereo” from left to left of center, or be centered somewhere along that path—in other words, most of the keyboard’s audio energy could be concentrated at the midpoint between the left and leftof- center points.
Remember, the whole point of most mixes is to create a great balance among all the instruments, where they sound like a cohesive ensemble but you can also differentiate among the various parts. The above tips can definitely help your keyboard synth snuggle comfortably into the mix with all the other instruments, yet retain its identity.