by Prof. Lydia Ayers

1
Exploring Music Lab 5

• by Prof. Lydia Ayers

2
Objectives

• Find the frequencies of your recorded samples
  from last week
• Flutes
• Trumpets
• Balloons
• Drinking straw double reeds
• Any other recorded sounds you made
• Analyze your sounds using pvan

3
Record a Sound for Me

• Please record a sample of the sound jack
• Use 44,100 sampling rate, mono
• Name the file cak_ your_full_name.wav
• Please indicate if you are male or female, unless
  you sign your email with a western name that
  makes it obvious
• Email the file to layers_at_cs.ust.hk
• I will use it in a piece and play it later in the
  semester

4
Find the Frequency of the Sound

• The Waveform Analysis program may help you find
  the frequency of your sound. (This program is set
  up to analyze Bell tones, so it may not work for
  every other kind of tone!)
• NOTE Great news about the Waveform Analysis
  program. This software is FREE, and you can use
  it on your home PC.
• http//www.hibberts.co.uk/intro.htm
• In CS Labs 1, 3 and 4 run it from the network
  l\apps\wavanal\wavanal.exe.

5
Find the Frequency of the Sound

• In the upper right of the window, chose Analyze
  Bell.

6
Find the Frequency of the Sound

• The Edit Partials window opens up

7
Find the Frequency of the Sound

• We are looking for a pitch around C4, frequency
  about 261.6, so ignore the lowest partial at 60
  Hertz and start with the 2nd one, 264.5. This
  tone may be slightly sharp (high). All the other
  frequencies (in the red box) form a nearly
  perfect harmonic series from this frequency.
• There is a lot of other information outside the
  red box, but it is not useful for our purposes.

8
Find the Frequency of the Sound

• Another way to find the frequency of your tone is
  to run a Spectrogram on it.
• www.visualizationsoftware.com/gram/gramdl.html
• NOTE Okay news about Spectrogram. This software
  is reasonably priced and good value for money,
  and worth buying if you want to use it on your
  home PC.
• On the File menu, chose Scan File and set the
  Pitch Detector on.

9
Find the Frequency of the Sound

• On the File menu, chose Scan File and set the
  Pitch Detector on.

10
Find the Frequency of the Sound

• Watch the upper right section of the screen and
  the analyis frequency will flash by (it's fairly
  quick, you can miss it if you don't pay
  attention).

• You can also place the cursor over the
  fundamental to get the frequency, but it changes
  as you move it along the line.

11
Running Pvan.exe

• Run PVan.exe.
• NOTE Great news about PVan. This software is
  FREE because Simon Wun, a former COMP342 TA,
  wrote the PC code for it, and you can use it on
  your home PC. If you meet him, feel free to pay
  him a compliment about it!
• http//www.cs.ust.hk/simon/pvan/index.html

12
Running Pvan.exe

• On the "File" menu, click the "New" button.

13
Running Pvan.exe

• Specify the input .wav file (2hornMid.wav) and
  analysis frequency in the dialog box.

14
Running Pvan.exe

• You should see a Perspective Plot when the
  analysis is complete (it may take some time)
• "Save As" to save and name your pv analysis file
  trumpetC4.pvn.

15
Running Pvan.exe

• If you see mostly black blobs like this, you
  probably entered the wrong frequency and you
  should try it again.

16
Running Pvan.exe

• Use the "Window" submenu and look at the graphs
  of the
• Perspective Plot
• Spectral Snapshot
• Amplitude Envelope
• Frequency Envelope

17
Perspective Plot

• Spectral Plot of Horn

18
Amplitude vs. Harmonic Plot

• Spectral Snapshot of Horn Tone One Second After
  Start of the Tone

19
Harmonic Amplitude vs. Time Plot

• Amplitude Envelope of First Harmonic of Horn Tone

20
Frequency vs. Time Plot

• Frequency Envelope of First Harmonic of Horn Tone

21
Frequency vs. Time Plot

• Frequency Envelope of First Harmonic of Horn Tone
• Noise in attack and at end of the sound
• Average pitch is not a straight line either!

noise
22
Running Pvan.exe

• Use the "File" submenu

• "Save As" to save and name your pv analysis file
• "Print" to print your graphs
• "Open" to reopen a saved pv analysis file
• Use the "Edit" Submenu
• "Copy" the image as a bitmap into another
  application

23
Composition

• If you have any extra time, you can work on your
  composition.
• Record and use any new sounds that you can think
  of
• Example of FORM Some compositions use an A B A
  form, and some use an A A B form
• If your rhythm composition is your A section,
  what would you use for a contrasting B section?