Math 5: Software
- FALL 2008
A word about computer audio formats:
recommend exporting to OGG (eg using audacity) for all your Aural postings.
WAV (.wav, `Microsoft Wave format') is
high quality but gives large files
(1MB gives only 6 seconds of stereo CD-quality)
- MP3 (.mp3, 'MPEG 3') is a proprietary format,
compressed so gives much smaller files
(1MB gives a full minute of stereo CD-sounding-quality at default
'128 kbit' rate). For our purposes this quality will be fine.
- OGG (.ogg 'Ogg Vorbis') is a free (non-proprietary)
format, equally compressed as MP3, sounding equally good.
Audio analysis, editing, conversion
Great for basic editing, viewing, multitrack, applying effects,
power spectrum of a selection,
reading/writing/converting MP3, OGG, WAV formats.
- Ctrl-1 zoom in, Ctrl-3 zoom out timescale
- Highlight a (mono) sound, not too short,
For better resolution change 512 to the largest size possible
(and choose a longer selection),
Linear frequency to
Log frequency and make it
fill the screen.
Powerful tool for spectrograms, spectra, voice analysis,
formant extraction and modification (eg gender changing!)
Interface is dorky, but is worth it. Reads WAV, not MP3 or OGG.
(also see online help)
- Once you've loaded a sound object, choose
and switch on
- Ctrl-n zooms to a (pink) selection
- Tab plays a selection
Spectrum->Spectrogram settings... I recommend
View range 0 to 2000 Hz, Window length 0.05 - 0.2 s (depending
on desired frequency resolution), dynamic range 40 - 50 dB.
- Ctrl-l takes power spectrum of selection, very useful to
then zoom in on to measure partial frequencies.
Professional audio analysis software, for playback,
spectrogram, spectrum. Comes in two versions: Raven Lite (free; does spectrogram but not spectrum),
and Raven Pro (free demo version runs for 10 mins;
otherwise $50 student license).
Beautiful interface, very flexible,
for recording, variable-speed playback, real-time spectrogram, spectrum.
Nearly as powerful as Raven or praat, easy to use, colorful, my favorite.
Reads WAV, OGG, not MP3.
- Pause start recording or stop, Alt-P play (highlighted section)
- Right-mouse-button brings menu up, eg to choose input source
- Alt-right, Alt-left zoom waveform timescale;
Alt-up, Alt-down zoom spectrogram timescale or waveform
or larger, for good resolution on frequency axis.
- To take power spectrum of a selection:
then use Middle-mouse-button to grab spectrum (then set
- Middle-mouse-button on spectrogram
brings up variable harmonic series lines
An elegant and useful little oscilloscope for real-time input only
by Luke Campagnola,
tweaked by yours truly. [Linux]
- spacebar toggle capture/restart
- 1,2 make line thinner/fatter
- Tab align view so trigger on right side
Spectrum (including averaged over a selection) and spectrogram, formants,
of sound files, and basic editing. Easy to use, not very flexible (eg
spectrogram length limited to 512 samples). [Windows,MacOSX,Linux]
- Amadeus II
Very nice real-time spectrogram and spectrum, editing, effects, conversion.
Trial version is free; $30 to buy.
WAV, MP3, OGG, many formats. [MacOSX only]
Can read audio files into arrays of numbers for analysis, graphing, processing.
Very powerful programming environment; I don't recommend it for this
course unless you already use it.
help on my Math 46 site. [Windows,MacOSX,Linux]