Due Sep 12, Peer grading due Sep 19

Fade In, Fade Out, Cross-Fade
You should be familiar with the terms fade in, fade out, and cross-fade. As a reminder, here’s a schematic to illustrate these terms. Remember that, when incorporating sounds into compositions, any sound without a “natural” beginning and ending should be edited with a fade in and fade out to avoid clicks and pops at the beginning and ending. When joining sounds together, one often overlaps the fade out of one sound with the fade in of the next sound, creating a cross-fade.

Instructions

• Obtain one or more sounds from freesound.org. (You may also record sounds of your own, including voice.)

• Using a sound between 3 and 5 seconds long, make a 1-second-long cross-fade from the sound to a copy of itself. Then, operating on the combined (spliced) sound, fade out over 2 seconds.

• Using the same sound, make a 20-ms-long cross-fade from the sound to a copy of itself. Then, operating on the combined (spliced) sound, fade out over 100 ms.

• Use Audacity to manipulate your sounds using splicing, mixing, and any effects you wish. The final mix should have a duration of 30 to 60 seconds. Your sound should either be a soundscape — layers of sound with different amplitude, panning, and effects — or a “beat” — a rhythmic sequence that loops. In either case, you should construct something original rather than using a ready-made sound. Use the envelope controls in Audacity to shape the loudness contour. E.g. you can fade in and out, ramp up to a climax, or create rhythm with amplitude change. Some form of loudness control should be obvious in your result. Your composition may be mono or stereo.

• Short answers in a text file:

  • What was your intention in the design/composition of your sound?

  • State the duration of your sound from part 3. To help our autograder, type a string exactly in the form: DURATION=37S (Note: all caps including “S”, no spaces, state the decimal integer number of seconds – rounded from the true duration – followed by capital S. The string “DURATION=” should appear only once in the file.)

  • Compute the size of the sound file assuming you save the file as a single-channel .wav file with 16-bit samples and a 44kHz sample rate. Does the number match the true size? To help our autograder, type a string exactly in the form: SIZE=180MB. (Again, all caps, no spaces, state the rounded-to-integer decimal number of megabytes – 1,000,000 bytes = 1MB – and “SIZE=” should appear only once with your answer.)

• Submit files in a zip file to Autolab. The following files should be at the top level in your zip file (you may use .aiff sound files instead of .wav sound files):
      sound0.wav: original sound used in Part 1 and Part 2
      sound1.wav: cross-fade/fade-in/fade-out sound, 1s cross-fade, 2s fade
      sound2.wav: cross-fade/fade-in/fade-out sound, 20ms cross-fade, 100ms fade
      origin/: a folder that contains the all the original sound files for your composition; if you have more than 10MB or 1 minute of sound, include representative sounds, keeping the total data in origin/ under 10MB.
      comp.wav: your composition
      answers.txt: short answers
      comp_README.txt: optional additional info on your composition
      origin/README.txt: optional credits and info on your source material

• Getting the right files in the right place is crucial. Unzip your file into a fresh location and check the resulting directory for each of the files and directories above. For example, your submission could contain the following:
      sound0.aiff
      sound1.aiff
      sound2.aiff
      origin/sound.aiff
      comp.aiff
      comp_README.txt
      answers.txt

• Grading is based on the following points:

  • Your submission should be anonymous.
  • Your cross-faded sounds should be correctly constructed.
  • Your answers for duration and size should be correct.
  • Your composition should not have any clipping.
  • Your composition should use the Audacity envelope tool or equivalent to make obvious loudness contrasts.
  • Your composition should show other editing or processing techniques.
  • Your composition should engage the listener.