When mixing songs that I didn’t record, I am often asked to make the synths, keyboards, and digital pianos “more realistic” to fit into the mix better. This can be considered a real challenge if you look at these types of sound sources as “fake”. Instead, I think of digital keys as simply a starting point for a more natural sounding result. Here are some techniques to take your software synths and digital keyboards to the next level.
Cut A Frequency Hole
Software synthesizers, especially those which emulate analog synthesis, often contact much more sonic material than needed. By simply making generous EQ cuts these synth parts can find a simple way to blend in a mix. I either take a cut at the low end, with a subtle makeup gain in the high end, or I push the mid range up a bit. This if often executed really well with a very colorful eq such as a pultec tub EQ or Neve 1073 EQ. If you don’t have a colorful eq like this, there are plenty of cheap mixer EQ’s that would do the trick (thats another post).
Add REAL Space
A Helpful technique lies not in expensive equipment, but using the acoustical space that the other instruments were recorded in. For synths that need to sound pristine, try setting up studio monitors in the recording room. Re-record the synth parts through Room mics set back from the monitors. You can also blend in some artificial reverbs to aid in the process. Careful placement of the room mics (like in a cinder block!) can have awesome affects.
If your synth part needs to rock a little harder, this same technique can be done with guitar amps, or a broken speaker. I find that using a gate in the signal chain (either before the amp, or after the room mic) can help to lessen the audio chaos in mix.
Drive Those Pres
For some more distorted color without the added “space” I often run synths back through very colored preamps. Any tube preamp driven hard will probably do the trick. Blend into the original source to taste.
My (big in size) little secret weapon is a cheap TAPCO spring reverb from a rack mountable mixer. The mixer is extremely noisy, but the eq and the reverb sound magical. It only works on certain sources, but when it works, there is nothing quite like it. I use the mic input, fader output, as well as the master output to control the amount of reverb, the distortion level, and the envelope of the reverb tail. Really an amazing tool for $20.