Advanced processing techniques: Pitch shift and time shift. Noise Reduction.

In this article I will explain what pitch allows us to do and how to reduce a noise. I will explain what are pitch options, I am going to focus on: time stretch and pitch shift. I will show you also how to do all of this processing techniques in Adobe Soundboot CS5 and few practical examples.

Pitch shift and time shift

Let’s start from explanation of pitch. What is it? It is process which allows you to change the track time, speed and tone (pitch). What more, this changes you can apply to whole track, then we are saying they are constant stretch, or can be changed in time, then we are calling them gliding stretch.

As you are guessing we can manipulate time, speed and tone of the track. There are few options of pitch which are converting sound:

  • Resample- changing number of samples per second, because of that it is influencing and changing also speed and tone. Unit of speed is % to the duration of the track, and unit of tone are notes, octaves.
  • Time stretch- changing the track time, but preserving its tone (pitch)
  • Pitch shift- changing the tone (pitch), but preserving its speed

Resample is a topic of other presentation, then let me explain two others effects.

Time Speed Tone
Time stretch change change preserve
Pitch shift preserve preserve change

More about time stretch effect. It is changing the speed or duration of an audio signal without affecting its pitch. When is it useful? It is used for example to match the pitches and tempos of two pre-record clips.

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Now about pitch shift. Is a process in which is changed the original pitch of a sound- is raised or lowered. Unit of pitch are octaves, which we can manipulate.

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When is it useful? It is widely used in music as effects units called pitch shifters or pitch benders used for example by guitarists. Devices are designed to raise or lower pitch by a pre-designated musical interval. Effect is also used in numerous cartoons to produce distinctive animal voices. Do you know that it has been used to create voice of Tweety or Daffy Duck?

How to apply this two processes in Adobe Soundboot CS5?

Choose PROCESOS> CAMBIAR TONO Y SINCRONIZACIÓN

Menu which should be open is showing picture below.

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For example to reduce the audio to half its current length, specify a value of extension of time of 50%.

To adjust the timbre of instruments and voices, and maintaining realism pitch shifts, select Preserve Speech Characteristics. To compare processed and original audio, click the power button.

How to do it is written down more specifically here.

PRACTICAL EXAMPLES

Actually it is different program, but example 1  all the time is valuable.

Example 2 is showing how to use that effect, but not on the computer, can be interesting for you (this video is in bad quality).

And last one example 3 is showing use pitch shifter to change a sound of guitar.

TV Adobe is showing more tricks and examples, it is possible to see the video here.


Noise Reduction

Second advanced processing technique which is available in Adobe Soundboot CS5 after opening Processes is Noise Reduction. Before I will explain how and why reduce it, let’s explain what is it noise at all.

So, noise is for example hiss caused by random electrons which influence the voltage of the output signal and thus create detectable noise. There are few kinds of noise: random, white with no coherence or coherent introduced by device’s mechanism. Noise is making audio less attractive for listeners, so that is why sometimes we want to cut it out.

Noise reduction is reduction of unwanted sounds, first selected, then it is possible to through it out from the whole record. Of course, it is not possible to cut it out perfectly, what is showing picture below.

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Translation of picture:

  1. reference signal
  2. signal with noise
  3. signal after reduce a noise

How to reduce the noise in Adobe Soundboot CS5?

Start from getting a profile of noise. In editor panel select a part that contains only noise. Then choose PROCESOS > CAPTURAR IMPRESIÓN DE RUIDO. Next step is to select in the editor panel PROCESOS> REDUCIR RUIDO. Menu which should be open is showing picture below.

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To compare processed and original audio, click the power button.

How to do it is written down more specifically here.

PRACTICAL EXAMPLE


TV Adobe is showing more tricks and examples, it is possible to see the video here.


CONCLUSION

Advanced processing techniques which I was explaining are widely used and the most of all are common. Time shifter is letting us to match the pitches and tempos of two clips, meanwhile pitch shift is widely used in music and also in cartoons. Noise reduction is letting us to improve audio, and make it more pleasant for ear.

I hope that after reading it you know how to use these effects in Adobe Soundboot CS5.

In Polish Thank you is “DZIĘKI”- so dzięki for reading!
Magdalena Oblak

Bibliography/webgraphy

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