Sound

One of the types of objects in Praat. For tutorial information, see all of the Intro.

## Commands

Creation:

  • Record mono Sound... (from microphone or line input, with the SoundRecorder)
  • Record stereo Sound...
  • Create Sound from formula...
  • Create Sound as tone complex...
  • Create Sound as gammatone...
  • Create Sound as Shepard tone...

Opening and saving:

  • Sound files

You can also use the text and binary (real-valued) formats for Sounds, like for any other class:

  • Save as text file...
  • Save as binary file...

Viewing and editing:

  • SoundEditor, ManipulationEditor, TextGridEditor, PointEditor, PitchTierEditor, SpectrumEditor

Playing:

  • Sound: Play
  • PointProcess: Hum
  • PointProcess: Play

Drawing:

  • Sound: Draw...
  • Sound: Draw where...
  • Sound: Paint where...
  • Sounds: Paint enclosed...

Queries:

  structure:
  • time domain
  • Get number of samples
  • Get sampling period
  • Get sampling frequency
  • Get time from sample number...
  • Get sample number from time...
  content:
  • Sound: Get value at time...
  • Sound: Get value at sample number...
  shape:
  • Sound: Get minimum...
  • Sound: Get time of minimum...
  • Sound: Get maximum...
  • Sound: Get time of maximum...
  • Sound: Get absolute extremum...
  • Sound: Get nearest zero crossing...
  statistics:
  • Sound: Get mean...
  • Sound: Get root-mean-square...
  • Sound: Get standard deviation...
  energy:
  • Sound: Get energy...
  • Sound: Get power...
  in air:
  • Sound: Get energy in air
  • Sound: Get power in air
  • Sound: Get intensity (dB)

Modification:

  • Matrix: Formula...
  • Sound: Set value at sample number...
  • Sound: Filter with one formant (in-place)...
  • Sound: Pre-emphasize (in-place)...
  • Sound: De-emphasize (in-place)...

Annotation (see Intro 7. Annotation):

  • Sound: To TextGrid...

Periodicity analysis:

  • Sound: To Pitch (filtered autocorrelation)...
  • Sound: To Pitch (raw cross-correlation)...
  • Sound: To Pitch (raw autocorrelation)...
  • Sound: To Pitch (filtered cross-correlation)...
  • Sound: To Pitch (shs)...
  • Sound: To Harmonicity (ac)...
  • Sound: To Harmonicity (cc)...
  • Sound: To PointProcess (periodic, cc)...
  • Sound: To PointProcess (periodic, peaks)...
  • Sound & Pitch: To PointProcess (cc)
  • Sound & Pitch: To PointProcess (peaks)...
  • Sound: To Intensity...

Spectral analysis:

  • Sound: To Spectrum...
  • Sound: To Spectrogram...
  • Sound: To Formant (burg)...
  • Sound: To Formant (sl)...
  • Sound: LPC analysis
  • Sound: To LPC (autocorrelation)...
  • Sound: To LPC (covariance)...
  • Sound: To LPC (burg)...
  • Sound: To LPC (marple)...

Filtering (see Filtering tutorial):

  • Sound: Filter (pass Hann band)...
  • Sound: Filter (stop Hann band)...
  • Sound: Filter (formula)...
  • Sound: Filter (one formant)...
  • Sound: Filter (pre-emphasis)...
  • Sound: Filter (de-emphasis)...
  • LPC & Sound: Filter...
  • LPC & Sound: Filter (inverse)
  • Sound & Formant: Filter
  • Sound & FormantGrid: Filter

Conversion:

  • Sound: Resample...

Enhancement:

  • Sound: Lengthen (overlap-add)...: lengthen by a constant factor
  • Sound: Deepen band modulation...: strenghten intensity modulations in each critical band

Combination:

  • Sounds: Convolve...
  • Sounds: Cross-correlate...
  • Sound: Autocorrelate...
  • Sounds: Concatenate

Synthesis

  • Source-filter synthesis tutorial
  • Manipulation (overlap-add etc.)
  • Spectrum: To Sound
  • Pitch: To Sound...
  • PointProcess: To Sound (pulse train)...
  • PointProcess: To Sound (hum)...
  • Pitch & PointProcess: To Sound...
  • Articulatory synthesis tutorial
  • Artword & Speaker: To Sound...

## Inside a Sound

With Inspect, you will see that a Sound contains the following data:

xmin
  start time, in seconds.
xmax > xmin
  end time, in seconds.
nx
  the number of samples ( 1).
dx
  sample period, in seconds. The inverse of the sampling frequency (in Hz).
x1
  the time associated with the first sample (in seconds). This will normally be in the range [xmin, xmax]. The time associated with the last sample (i.e., x1 + (nx − 1) dx)) will also normally be in that range. Mostly, the sound starts at t = 0 seconds and x1 = dx / 2. Also, usually, xmax = nx dx.
z [1] [1..nx]
  the amplitude of the sound (stored as single-precision floating-point numbers). For the most common applications (playing and file I-O), Praat assumes that the amplitude is greater than -1 and less than +1. For some applications (modelling of the inner ear; articulatory synthesis), Praat assumes that the amplitude is expressed in Pascal units. If these interpretations are combined, we see that the maximum peak amplitude of a calibrated sound is 1 Pascal; for a sine wave, this means 91 dB SPL.

## Limitations

Since the Sound object completely resides in memory, its size is limited to the amount of RAM in your computer. For sounds longer than a few minutes, you could use the LongSound object instead, which you can view in the LongSoundEditor.

### Links to this page

- band filtering in the frequency domain
- DTW & Sounds: Draw warp (x)...
- DTW & Sounds: Draw...
- Extract one channel...
- FLAC files
- FormantPathEditor
- Formants & LPC menu
- Formulas 1.6. Formulas for creation
- Formulas 1.7. Formulas for modification
- Formulas 8. Attributes of objects
- How to concatenate sound files
- Intro 1.2. Reading a sound from disk
- Intro 2. What to do with a sound
- Intro 2.1. Saving a sound to disk
- Intro 2.2. Viewing and editing a sound
- Intro 3.1. Viewing a spectrogram
- Intro 3.8. The Spectrum object
- Intro 4.1. Viewing a pitch contour
- Intro 4.5. The Pitch object
- Intro 5.1. Viewing formant contours
- Intro 5.4. The Formant object
- Intro 6.1. Viewing an intensity contour
- Intro 8.1. Manipulation of pitch
- Intro 8.2. Manipulation of duration
- Intro 8.3. Manipulation of intensity
- LPC & Sound: Filter (inverse) with filter at time...
- LPC & Sound: Filter with filter at time...
- Manipulation: Extract original sound
- Manipulation: Replace original sound
- MixingMatrix
- NIST files
- Periodicity menu
- pitch analysis by filtered autocorrelation
- pitch analysis by filtered cross-correlation
- Play
- PointProcess: To Sound (phonation)...
- Read separate channels from sound file...
- Record Sound (fixed time)...
- sampling frequency
- sampling period
- Save as AIFC file...
- Save as AIFF file...
- Save as FLAC file...
- Save as NeXT/Sun file...
- Save as NIST file...
- Save as WAV file...
- Sesam/LVS files
- Sound & Formant: Filter (no scale)
- Sound & FormantGrid: Filter (no scale)
- Sound & IntensityTier: Multiply
- Sound & Pitch: Change gender...
- Sound & Pitch: Change speaker...
- Sound & Pitch: To Spectrogram...
- Sound files 1.2. Quantization
- Sound files 2.2. AIFF files
- Sound files 3. Files that Praat can read
- Sound: Change gender...
- Sound: Change speaker...
- Sound: Extract Electroglottogram...
- Sound: Extract part...
- Sound: Fade in...
- Sound: Fade out...
- Sound: Formula...
- Sound: Multiply by window...
- Sound: Play as frequency shifted...
- Sound: Remove noise...
- Sound: Scale intensity...
- Sound: Scale peak...
- Sound: To BarkSpectrogram...
- Sound: To ConstantQLogFSpectrogram...
- Sound: To Covariance (channels)...
- Sound: To CrossCorrelationTable...
- Sound: To Formant (keep all)...
- Sound: To Formant (robust)...
- Sound: To FormantFilter...
- Sound: To FormantPath (burg)...
- Sound: To KlattGrid (simple)...
- Sound: To Ltas (pitch-corrected)...
- Sound: To MelSpectrogram...
- Sound: To MFCC...
- Sound: To Pitch (ac)...
- Sound: To Pitch (cc)...
- Sound: To Pitch (filtered ac)...
- Sound: To Pitch (filtered cc)...
- Sound: To Pitch (raw ac)...
- Sound: To Pitch (raw cc)...
- Sound: To Pitch...
- Sound: To Polygon...
- Sound: To PowerCepstrogram...
- Sound: To Sound (derivative)...
- Sound: To Sound (whiten channels)...
- Sound: To Spectrogram (pitch-dependent)...
- Sound: To Spectrum (resampled)...
- Sound: To TextGrid (silences)...
- Sound: To TextGrid (speech activity)...
- Sound: Trim silences...
- Sounds: Combine to stereo
- Sounds: Concatenate with overlap...
- Source-filter synthesis 1. Creating a source from pitch targets
- Source-filter synthesis 4. Using existing sounds
- Spectrum: Tabulate (verbose)
- Spectrum: To Sound (resampled)...
- SpellingChecker
- stereo
- TextGrid
- VowelEditor
- What was new in 3.6?
- What was new in 3.7?