Basic Synthesis: Part 4 – Effects Part 1

by Derrick Hakim Comment Closed
Effects, while not technically a stage of any form of subtractive music synthesis, are commonly found on the end of most signal paths from synthesizers. Effects can come in an internal form (built into your synthesizer), and in an outboard form (where it is a separate effects box, such as a rack mount unit or pedal). While internal effects are useful parts of synthesizers as they save on space and power, they are usually not as high quality as a dedicated external effects unit, but will suffice for most users. Bear in mind when purchasing a vintage synthesizer, that many older models (from the 1970s and 80s) will most likely not have any form of built in effects. Unison: In similar fashion to effects not technically being part of sound synthesis, unison is not really an effect, but more of a fixed option within your synthesizer. The effect of unison is simply to multiply the signal which is being produced by...
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Basic Synthesis: Part 3 – Envelopes

by Derrick Hakim Comment Closed
Envelopes are the key to the articulation of your sound. Without them your patch will immediately start off at full blast, and stay there, and then disappear all of a sudden when you let go of the key. Envelopes, although difficult to understand at first allow you to change that, so you can create expressive and dynamic sounds with your synthesizer. The standard envelope is in 4 main stages, described below: Attack – the sound rising up to its maximum level. If it’s set to nothing, the sound plays at full blast straight away, whereas if you set it quite high then the sound gradually fades (good for string sounds). Decay – this is how long the sound stays at the level the attack brings it up to. If it’s set as high as it will go, it will stay at the maximum level forever (rendering the sustain stage useless). Sustain – this is the level that the sound stays at after the decay...
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Basic Synthesis: Part 2 – Filters

by Derrick Hakim Comment Closed
Filters are one of the most important parts of sound creation, and they are a foundation to the whole concept of ‘subtractive’ synthesis. The filters do exactly that – they filter out part of the sound, leaving you with a reduced portion of it, which sounds very different to the whole portion. The main control on any filter is the filter frequency, or ‘cutoff’, which is the key point at which all frequencies are cut off – be it all frequencies which are above, below, in between, or outside of the cutoff point. Common filter types include: Low Pass – the most common type of filter, the low pass allows all frequencies below the cutoff point to pass through. High Pass – the opposite of the low pass filter, the high pass filter allows all frequencies above the cutoff point to pass through. Band Pass – allows a band on frequencies to pass through in the centre, but stops all frequencies outside of...
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Basic Synthesis: Part 1 – Oscillators

by Derrick Hakim Comment Closed
Without oscillators, your synthesizer will make no sound (well, actually it can - but that's in a future article). Oscillators produce the original sound which you can hear in your patches, which is then fed through the rest of the signal path in the synthesizer. Oscillation itself is the production of a certain type of waveform, which produces a different sound depending on the shape of the waveform. The waveform is constantly ‘run' depending on the speed/pitch of the note - so if an oscillator is set to a low enough pitch you will eventually hear gaps due to the slow speed of oscillation (see LFO below). Common oscillator waveforms are: Saw Wave - shaped like the teeth on a saw blade, this produces a very common sharp, biting tone. Square Wave - looks like a (near) perfect square, produces a reedy, hollow sound. Pulse Wave - a variation on the above, the pulse wave is half as wide as a square wave,...
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