1 / 24

Subtractive Sound Synthesis

Subtractive Sound Synthesis. Subtractive Synthesis. Involves subtracting frequency components from a complex tone to produce a desired sound Why is it not worth trying to subtract frequencies from a sine wave? A sine wave only contains one frequency. Subtractive Synthesis.

celina
Download Presentation

Subtractive Sound Synthesis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Subtractive Sound Synthesis

  2. Subtractive Synthesis • Involves subtracting frequency components from a complex tone to produce a desired sound • Why is it not worth trying to subtract frequencies from a sine wave? • A sine wave only contains one frequency

  3. Subtractive Synthesis • Unwanted frequencies are attenuated using filters • The most basic subtractive synth needs at least one oscillator and one filter

  4. Subtractive Synthesisers • Subtractive synths provide: • two or more oscillators • a noise generator • at least one filter • at least one envelope • an LFO • a modulation matrix

  5. Filters • Used to attenuate spectral components • Implemented using electronic components or a digital algorithm

  6. Filter Types • Low Pass Filters • High Pass Filters • Band Stop Filters • Band Pass Filters

  7. Cut-off frequency Amp. Frequency Low Pass Filter • Lets through everything below a certain frequency

  8. Filter Slope • Ideal filters are like brick walls • All real filters have slopes • So some sound gets through beyond the cut-off

  9. Filter Slope roll-off dB 500 8000 KHz A low pass filter with a gentle slope of 6dB per octave.

  10. Cut-off frequency Amp. Frequency High Pass Filter

  11. Centre frequency Amp. Frequency Band Pass Filter

  12. Centre frequency Amp. Frequency Band Stop Filter

  13. Envelopes • Determine how the value of a certain parameter of a sound changes over time • Can be used to alter any parameter, e.g. pitch

  14. Amplitude Envelopes • How the amplitude varies over time affects the character of a sound significantly • So most synthesisers have an amplitude envelope

  15. attack decay sustain release amplitude time

  16. Amplitude Env. Parameters • attack – occurs at the start of the wave and is the time it takes for the sound to reach peak amplitude • decay – the time it takes for the peak amplitude to fall back (possibly to zero) • sustain – the amplitude level the sound will fall back to following the initial decay • release – the amount of time it takes for the sound to fall back (or decay) to zero after the sustain period (or after the key is released)

  17. TS404 AMP ENV Subtractor AMP ENV

  18. Modulation • Modulation traditionally means to change the key of a piece of music • With synths it means to alter a parameter (target) in accordance with another signal (source) • Example targets: amplitude, pitch, cut-off

  19. Modulation • Example sources: envelope, LFO, velocity • Alter the intensity of the modulation over time • Slider often used to alter the max extent of the modulation (the intensity of the overall effect)

  20. Hardwired Modulations • The ESP allows the LFO to be applied to: • frequency (pitch) of oscillators; or • the cut-off frequency

  21. L.F.O. • Low Frequency Oscillator • 0.1 – 20Hz • Can be synched to the project tempo

  22. LFOs

  23. Modulation Matrix • Target: parameter to be altered • Source: signal that is used to alter target • Slider: sets modulation intensity • Via: varies modulation intensity by another parameter

  24. The ES2 Modulation Matrix

More Related