Tutorials and Topics - Peabody Computer Music

Tutorial 6A review of fundamentals1. You will need a second cycle~ object to produce the tone a 12th higher.2. To obtain the frequency that’s a (just tuned) perfect 12th above E, simply multiply329.627557 times 3. The frequency that’s an equal tempered perfect 12th above E is987.7666 Hz. Use whichever tuning you prefer.3. In addition to the amplitude envelope for each note, you will need to change the overallamplitude of each tone over the course of the ten seconds. This can be achievedusing an additional *~ object to scale the amplitude of each tone, slowly changing thescaling factor from 1 to 0 for one tone, and from 0 to 1 for the other.Exercise 3• Modify your second patch so that, over the course of the ten repeated notes, the twocrossfading tones also perform an over-all diminuendo, diminishing to 1 / 32 theiroriginal amplitude (i.e., by 30 dB).Hints:1. This will require yet another amplitude scaling factor (presumably another *~ object)to reduce the amplitude gradually by a factor of .03125.2. Note that if you scale the amplitude linearly from 1 to .03125 in ten seconds, thediminuendo will seem to start slowly and accelerate toward the end. That’s becausethe linear distance between 1 and .5 (a reduction in half) is much greater than thelinear distance between .0625 and .03125 (also a reduction in half). The first 6 dB ofdiminuendo will therefore occur in the first 5.16 seconds, but the last 6 dB reductionwill occur in the last .32 seconds. So, if you want the diminuendo to be perceived aslinear, you will have to adjust accordingly.Solution to Exercise 1• Scroll the example Patcher window all the way to the right to see one possible solutionto these exercises.94