Assignment 3: Trying out Csound

Goal

To understand how basic Csound opcodes work and to listen to sound produced by simple orchestra files.

Task list

 

  1. Read through the ‘toot’ tutorial at http://www.keele.ac.uk/depts/cs/Stephen_Bostock/webteaching/C-Sound_Tutorials/Index.htm (also at http://www.csounds.com/toots/index.html) and try each section by downloading the files and running csound on each one. The command on music1 or music2 is simply csound followed by the .orc file and the .sco file. E.g.:
        csound -o dac toot1.orc toot1.sco
    You should hear the sound generated by the orchestra file and played by the score file. If you do not, contact me.
  2. Answer the following questions:
    1. In toot01, what happens to the sound produced if you alter sr in the .orc header to 22050, and kr to 2205?
    2. In toot02, what happens to the output if you change all the note durations (p3) in the .sco file to 2 seconds?
    3. In toot03, what happens if you reduce the attack time (p6) to 0?
    4. In toot04, describe the change in the output sound if you alter the detuned frequencies to 1.001 and .999.
    5. In toot05, what change would you make to have the time of the delay until vibrato starts come directly from p10 rather than be calculated from it and from p3?
    6. In toot06, what do you hear if you use the GEN10 function method to produce only even harmonics? [In particular, note that the fundamental, being an odd harmonic is given amplitude 0].
    7. In toot07, alter the .orc file so that each note length is split into two equal parts, and the p13 governs the length of the crossfade. For instance, if the length of a note is 5 seconds, and p13 is 0.2, then the first oscillator will sound for the first 2.3 seconds, then the second oscillator will be crossfaded for 0.2 seconds, and then the second oscallator will finish the note up to 5 seconds. [ You will need to alter the linseg for kfade accordingly].
    8. In toot08, alter the use of p9 to be a ratio (between 0 and 1) of the "wet" signal (with reverb added) to the "dry" signal with no reverb. Thus if p9 is 0.5, the wet and dry signals will be the same amplitude. If p9 is 0.8, then the wet signal will be 4 times as big as the dry signal (i.e. 0.8 / 0.2). Use this file as the input for the reverberator.
    9. In toot10, make the frequency parameter of the reson opcode (it's first parameter) modulated by the output of a low frequency oscillator instead of by a line envelope. [Look at the vibrato example in toot05 to see how this is done].

Deliverables

The answers to questions 1-9. Where the orchestra or score files have been changed, give the new versions.