Synthesizers create the music of the modern age by expanding our horizons in the possibility of sound. With the vast array of synthesizers out there, not to mention the hundreds of different controls that come on most high-end units, trying to get acquainted with the idea of sound synthesis can be a bit frightening. To truly understand how synthesizers work, you have to break them down into their simplest pieces. Today we’re going to take a journey to explore the magical world of synthesis, and more specifically, subtractive synthesis, one of the more popular types in modern music.
An oscillator is the most important foundational element of a synth that essentially generates tone for you to eventually manipulate with other controls. An oscillator creates a simple tone for you as a future synth guru to shape and sculpt into sounds that are more elaborate or ones that you may be used to hearing in your favorite songs. You’ll typically find between 2-3 oscillators on synths that can range from wave oscillators to sub oscillators to noise oscillators. You can then choose to mix these together however you like in terms of volume.
Harmonics and Wave Shapes
Oscillators will typically come with adjustable wave shapes that sound much different from one another or give them their own unique timbre. The timbre of an instrument is the reason a tuba sounds different from a guitar or a piano sounds different from an upright bass. Some of these wave shapes that we typically find on synthesizers are saw, sine, square, and triangle. The way we create these wave shapes is by adding harmonics to them. Saw frequencies have many harmonics added, and therefore sound thicker, richer, and more powerful, while sine frequencies do not have any added harmonics so they are purer and softer. We could spend forever going down the rabbit hole of harmonics and wave shapes, but the important thing for you to grasp is that additional harmonics are essentially the skeletal structure that make one wave shape different from the next.
Another foundational piece of subtractive synthesis is filtering. Filters essentially filter out a section of sound to leave you with a diminished sound. You use the ‘cutoff’ parameter to decide where in the frequency spectrum you want to start cutting. You’ll typically see these labeled as High Pass (allows for frequencies above the cutoff), Low Pass (allows for frequencies below the cutoff), Band Pass (allows for frequencies within two cutoffs), and Notch (stops a small region of frequencies from being heard). You can add or subtract specific frequencies at specific dB ranges to alter your sound further. The second most important parameter known as ‘resonance’, works in conjunction with the cutoff to enhance the frequencies right before the cutoff. This is where you get sweeps, falls, and transitional fx in electronic music.
The last section of a basic synthesizer before reaching the amp runs through what we call ‘envelopes’. Envelopes make it possible to alter the articulation of your sound to make it more dynamic and musical. The four main envelopes are ‘attack’ (the sound at max level during the initial hit), ‘decay’ (how long the sound will remain at the max attack level), ‘sustain’ (how long the sound remains alive after the decay), and release (how long it takes for the sustain to completely die out and become silent). These can be hard to grasp at first, but we’ll to make it a bit easier. Let’s take ‘attack’ for example. A violin will have less ‘attack’ than a snare, as the max sound on a violin takes a while to build while a snare’s max sound is instant. Therefore if you want a string-like sound, you would pull the ‘attack’ time back. As for ‘decay’, a pedaled piano would have more ‘decay’ than trumpet hit. Therefore if you wanted a more piano-like sound, you would add more ‘decay’. Always imagine your synth as an acoustic instrument and imagine how they are played to start setting your envelopes properly.
LFOs, Modulation, Effects, Etc.
While I could go deep into all of these, it may not make sense as all synthesizers have different qualities. This is what makes a Minimoog different from a Juno and different from a Buchla Easel and so on and so forth. To generalize it, these are the parameters that take the sound you have created and affect it to make it interesting and give it real movement. After all, electronic music is mad great because it is constantly moving and evolving. How else do you think Daft Punk can keep a 6-minute long dance song with the same progression interesting?
Beginner Synth – Korg Minilogue
The first reason why I picked the Korg Minilogue is because it is a polyphonic synthesizer, meaning you can play it like a piano with multiple notes at once. Not only does this synthesize sound amazing, but the range on it is incredible as well. It’s an extremely flexible four-voice synthesizer that comes with 100 built-in presets and room to program 100 more. You also have the ability to route those sounds into an automatable 16-step motion sequencer to get spacey and connect it via USB to your laptop or computer to use as a MIDI keyboard. KORG is one of the most reputable synthesizer brands around and offer a wide array of synths that are perfect for beginners. The Minilogue is only one of the first to come to mind.
Intermediate Synthesizer – Dave Smith Instruments Prophet 8
One of the most classic polyphonic synthesizers from the 80s was the Prophet 5. Now extremely hard to find and wildly expensive, it’s difficult to recommend them to anyone. Luckily, Dave Smith revamped this polyphonic synth and brought it to the new age with the Prophet 8. This 5-octave weighted key synth looks just like the classic, except it comes loaded with presets and an incredibly powerful effects engine that makes the playability, tweakability, and reliability, much better than the original. The first time I messed around with one of these I was absolutely blown away.
Advanced Synthesizer – Moog Minimoog Model D
It’s pretty difficult to write out an article about synthesizers without mentioning this one-of-a-kind, legendary monophonic synth. It’s pretty much an exact replica of the Minimoogs that were being made in the 50s and 60s. It is by far one of the most expensive synths out there, though the fact that its vintage sound is unique to anything else backs that up. The reason we label this as an advanced synth is because it is monophonic and does not have any presets built-in. This means you will be left to work to and create the sounds from the ground up.