Omg what the hell is an article like this doing on Ultimate-GUITAR?Let's go back a paragraph, to the one that, you know, you just read. (Right?) Every once in a while, a question about electronic music comes up on UG, either because someone really wants to get into it (for some reason), or (more often) because some ignorant scrub ran their mouth off about "techno" or "dubstep" for the millionth time. This is a guitar site, yeah, but anyone who's been to the Pit knows it's not *just* a guitar site. Especially for recording guitarists, it's important to she'd some light on peripherally related music topics, and this is one of them.
How sound worksWhat your ears hear, and what your brain interprets as sound, is a pattern of what we call traveling waves moving through the air. You know, traveling. Through the air. Your ear picks up patterns of compressed or stretched ("rarified") air, and your brain interprets those patterns to turn you into a blubbering mess when it hears "My Heart Will Go On." Like dis if you cri everytim:'(. In audio electronics, those patterns are encoded as digital values, or sent as analog voltages. Either way, a wave can be plotted on a graph as a function of amplitude versus time, or a waveform. You know what these look like. If you don't, open up your favorite song in Audacity. Then zoom in. Then zoom in. Then keep zooming in. That's a waveform. Then zoom all the way out. That's the whole waveform. It's really the same thing, but zooming in shows a smaller part of it. Physical instruments (like a guitar) make sound by making the air around them vibrate. They mostly do this by making a string vibrate, then transferring that vibration to the whole instrument, and then the air (guitars, violins, and pianos), or passing air through them, and restricting how that air vibrates (trumpets, flutes, didgeridoos and other wind instruments). An electric guitar then takes that vibration and turns it into a signal, which is amplified and turned back into sound with a speaker. Audio synthesis is a bit like that, except we build that signal electronically. Over two hundred years ago, a French guy named Jean Fourier was studying hieroglyphs in Egypt, when he suddenly created a field of science that had absolutely nothing to do with his work. The people paying him to do things that had nothing to do with what we're talking about were not amused. Anyway, Fourier theorized that any waveform could be created by adding together sine waves at multiples of the same frequency. So, say, a sine wave at 100Hz, another at 200, 300, 400, etc, could make any type of waveform (at 100Hz), if you shifted them, and set each one to the right loudness. We call the lowest one the fundamental. Say, you play the fifth fret on the high E string; that's an A4, and the fundamental will be 440Hz. You'll hear (subconsciously) other frequencies, or overtones, at 880, 1320, 1760, 2200, and so on. In synthesis, even though you can't see them in a waveform, overtones are important, since they define the timbre, or character, of a sound. It's what separates a horn from a violin, or a bright piano from a harp. Or an amp's crunch channel from the lead channel. Just remember: a note at a certain frequency is made up of sine waves at that frequency, twice that frequency, three times that frequency, and so on until you need to upgrade your computer because you're making music for bats. It's a niche market, sure, but a totally untapped one. There's probably plenty of money in it.
OscillatorsThere are different types of synthesis, but the easiest one to learn is subtractive synthesis. Basically all synths have some capacity for it. Subtractive synthesis works by starting with a really simple waveform, made from a basic geometric shape, and processing it until it sounds like what you want. Back before software synthesis, these waveforms were made with circuits called oscillators, and even though that's not really how it works with software, we still call the starting points of subtractive synthesis "oscillators." To do digital software synthesis, you'll need a synthesizer, along with a host program (probably a DAW, or digital audio workstation, like Cubase, FL Studio, or Logic) to run it in. If you have a DAW already (Audacity doesn't count), it'll probably come with a few different synthesizer plugins out of the box. I usually use Image-Line's Sytrus for synthesis, through FL Studio, but most subtractive synths have all the most important features. For example, most of them can make five basic waveforms with their oscillators:
FiltersA pure sawtooth wave sounds like ass. No really, some of the lower-quality saw-based brass sounds literally sound like a person farting. To fix that, let's get to the part of subtractive synthesis that makes it subtractive synthesis: the filter. A filter works by making all the frequencies above and/or below a certain spot, called the cutoff frequency, quieter. Filters mostly affect the overtones, which, again, are the reason every instrument doesn't just sound like a boring sine-wave "beeeeeeep", so they can affect the sound's timbre dramatically. There are four main different types of filter:
You can change controls automaticallyYeah, that. There are two main ways to make a control (like an oscillator's volume, or a filter's cutoff) change automatically, over time. LFOs, or Light Funky Oscillators, are- oh, Low Frequency Oscillators, are oscillators that oscillate a low frequency. Like, not high enough to make an audible pitch; a few times per second, or less. You can change an LFO's waveform, leading to different types of behavior; a square wave will go from fully on to fully off, and a sine wave will smoothly sweep between the two extremes. For example, you can use a sine LFO hooked up to the filter cutoff to make a simple dubstep wobble. Don't get too cocky, though. The big names use FM synthesis, which is- just don't go there. It's insane. Envelopes are cycles activated when a note is played. They usually have four phases, defined with four values you can enter:
Advanced-level $#! +A good synth will have a ton of other controls to alter its sound even more. Here are a few:
EffectsAfter your synth has done everything it can do, the signal is routed into your DAW. You can put effects on the output to modify the sound even more, but by now, it's already been mixed into a signal. No fancy stuff like messing with the pitch or anything like that. This part is kind of like adding pedals to your guitar/amp's FX loop, and by "kind of," I mean "exactly," this is literally the exact same thing.
ExamplesOkay, enough abstract BS. If you're describing music and sound, there's not much you can do with just words. So here are some examples of synth sounds in rock and metal songs, and how they're made: Europe - "The Final Countdown" (intro):
Ta-daaYou can program basic synth sounds now. Take what you've learned and experiment with it. If you don't know what a knob does on your synth, turn it. The part of sound design that most people miss is trial and error. If you like how something sounds, save it as a preset, so you can come back to it later if you have a song that would sound good with it. That's how electronic music works.