Now that we have taken a look at a few of the basic components involved with synthesis including oscillators, types of waveforms and how to combine waveforms to create complex sounds, I’d like to take a minute to talk to you about some of the various Filters we have at our disposal to facilitate us in shaping our sound, as well as explore Envelope Generators and their respective parameters. Once you start to fully understand the range of functionality you get with these tools in synthesis, you will see that you have unlimited possibilities in creating your sound.
As we discuss various filters and parameters, please keep in mind I am only covering the general categories of filters, as there are thousands of different synthesizers on the market, each with their own specific components and filters to learn and manipulate.
Filters are the most important tools for shaping the overall timbre of the sound. Filters allow you to route your waveforms through circuits that you can use to greatly affect many of the characteristics of your sound. Filters primarily have 2 main parameters for manipulation: Frequency and Resonance. The Frequency Slider allows you to choose which frequency will be affected by your filter, and Resonance allows you to boost or attenuate your selected frequency. Basically, filters allow you to select particular frequency ranges, affect them with the particular filter and boost or cut the end result of this process.
As I previously mentioned, there are MANY different types of filters out there on different synthesizers, but we will be focusing on a few of the more common filters out there, and take a look at how they can shape our sound. Lets take a look at 4 different common filters you can use to shape your sound and briefly explain how they work. These 4 filters are Low Pass, High Pass, Band Pass and Notch Filters.
Low Pass filters allow low frequencies to pass through while rejecting higher frequencies. Similarly, the High Pass filter allows highs to pass while rejecting low frequencies. In this way, we can cut out unwanted lows that are making our sound too muddy or boomy, or we can remove some high frequencies that can make our sound too bright. Again, the resonance parameter on each of these filters allows you to choose which frequencies you would like to boost or cut. Along with these, most synthesizers have a Band Pass filter, which allows you to select a band of frequencies anywhere in the frequency spectrum to allow these to “pass through” the band. Conversely, the Notch filter (aka Band Reject filter) operates opposite of the band pass filter, meaning it allows you to select a band of frequencies to reject, allowing the remaining frequencies to pass through.
The real beauty of filters comes when you combine multiple filters to create complex effects within your sound creation. For example, you could use a band pass filter to select a mid-range frequency to boost, then route that signal to a low pass filter in order to slowly boost or attenuate the sound over time. This works well in club and electronic tracks as it can really help to build up the emotion of the song as you prepare the crowd for a big drop.
Finally, we will take a minute to discuss Envelope Generators, explaining how these powerful tools allow us to affect our sound over time and covering the 4 main parameters these envelopes offer us in sound manipulation.
Envelope Generators control how the sound is carried out after it is triggered. These envelopes dictate what happens to your sound after being triggered by the synthesizer. These can be applied either to the oscillator, the amplifier or the filters, resulting in different changes for each such as change in pitch, volume, vibrato and much more. There are 4 main parameters that allow you to control how this happens, and we will use an amplitude envelope to take a look at these parameters and their function.
Attack – determines how quickly a sound reaches its peak level after the sound is triggered; an attack of 0 triggers the sound immediately, while this can be adjusted out for more build-up before your sound reaches full volume.
Decay – determines how quickly a sound drops to a lower level that it will remain at after it reaches its peak. NOTE: if your sustain level is higher than your decay level decay will be negated.
Sustain – determines the level that your sound remains at AFTER the decay until the key is released.
Release – determines how quickly the sound level fades to nothing after the key is released.
As you can see, the more you explore and combine these sound generators, filters and envelopes, the more complex your sound can become. I encourage you to play with different combinations of these tools, as you will quickly start to realize how they interact with each other and be well on your way to manipulating sound to your heart’s desire. Next week we will wrap up our series on basic synthesis and I will demonstrate some of what we have covered by creating a track using synthesizers I have created with this basic knowledge. Make sure to follow us on twitter @_signaturesound and @iamjambot to stay plugged in to everything that is happening over here at Signature Sound, and while you’re at it come check out our upcoming MIX EVENT with Christian Cummings here at the studio! Seeya next week!