1. 1 Manipulating Digital Audio

2. 2 Digital Manipulation  Extremely powerful manipulation techniques  Cut and paste  Filtering  Frequency domain manipulation  Significantly reduced noise problems  Error detection and recovery

3. 3 Cut and Paste

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6. 6 Effects  There are many manipulation techniques that can be used to change the digital audio  Remove noise  Add reverb  Increase dynamic range  Filter boost or attenuate particular frequencies  Alter Pitch/Tempo

7. 7 Delay and Echo  Repeating the the sound at a delayed time can have the following effects  >35ms discrete echoes  35<>15 simple chorus effect  15< spatially locate a mono sound  Echo is a repeated delayed sample that decays

8. 8 Flanging  Flanging involves a time delay and a phase shift  Gives a psychedelic sound to audio

9. 9 Reverb  Reflections are characterised by relative loudness and delay  Digital reverberation is ideally suited to changing these characteristics to simulate different acoustical environments  Reverb is different from the basic echo function in that the delays are not repeated at regularly spaced intervals

10. 10 Reverb

11. 11 Graphic Equaliser  Enables the boosting or attenuation of the signal at particular frequency bands

12. 12 Filtering  Before  After

13. 13 Pitch Stretching  Changing the frequency of the wave  Increasing the pitch transposes frequencies high up the range

14. 14 Tempo  Duration of the wave

15. 15 Amplitude Envelope  This specifies the amplification with respect to time  Enables the fading in or out of sounds

16. 16 Amplitude Dynamic Range Processing  Varies the output amplitude of a waveform, based on its input level  Can boost low amplitude (quite sounds)  Can attenuate high amplitude (loud sounds)

17. 17 Channel Mixing Left Right

18. 18 Pan and Balance  Pan  The proportion of a mono signal which is fed to left or right speakers  Balance  The relative attenuation of each channel of a stereo signal

19. 19 Multiple Tracks

20. 20 Fin