Synth keyboards seem to be popping up in every conceivable genre of music, and they’re getting more versatile as technology improves. With great versatility comes great responsibility, though, and a synth isn’t anything if you don’t understand just a little bit of the science behind how the sounds are made. Here are the four basic types of waves that a synth utilizes, with explanations of why they sound different, so that you can build and use better synth voices for your songs.
1. Sine – These are basic waves, and sort of the building block for non-sinusoidal wave types. A pure sin wave sound will have a smooth, natural tone on a synthesizer, and many of the less harsh voices on a synth will use a sin wave as a starting point. Tones with purely sinusoidal waves are said to be “pure tones” because of their natural and simple sound. It’s easy for an ear to process.
2. Cosine – This is basically a sin wave with a head start, as cosines begin at a different point relative to the sine wave. By layering multiple sin and cosine waves on top of each other, synthesizers can create recognizable harmonics and busy, noisy, or otherwise interesting sounds that are more complex than the basic sine or cosine wave alone. Making voices on the synthesizer consists of a lot of layering of different wave types or the same wave types with different wavelengths, leading to interesting effects.
3. Sawtooth – The sawtooth wave looks like its namesake; it rises sharply from 0 to the maximum possibility, then drops back down and repeats. This makes for a sharp, harsh sound, with a distorted type of tone. It’s one of the most commonly used wave types, since it gives synth voices a unique quality that isn’t really re creatable in other instruments, letting the synth stand out in a busy mix and giving it a unique tone.
4. Square – The square wave sounds more distorted than the square tooth wave, typically, a harsh sound used for the same purposes as the squaretooth. It’s a good starting point for lead and bass synth voices. Because both the sawtooth and square waves are non sinusoidal, they contain a number of sin waves to make their unique sounds. In the case of the square wave, effects like flange and reverb can serve to enhance tone and make a more unique sound. As the name implies, a square wave goes suddenly between one point and another, with an instantaneous (rather than curved) change.
Do you have questions about these types of audio waves, or synth questions in general? Post in our comments section below.