ARP2600 - Fundamentals of Music Technology - Cyborgstudio.com

068 - SECTION EIGHT: THE VCAEXPERIMENTS FOR SECTION EIGHT1. Connect the VCF to the VCA. Demonstrate that this is a redundant patch. Use the lowest initial gainsetting to ‘gate’ the incoming sound and use an EG to open and close the VCA.2. Connect VCO-3’s saw output to one of the audio inputs on the VCA. Raise its attenuation slider. Trymoving the initial gain slider to determine its effect on the sound.3. While conducting experiment #2, connect a sine wave from VCO-2 in LF mode to the linear controlinput. Raise its attenuation slider. Try changing the attenuation of both the incoming audiosignal and the incoming control voltage. After observing the effects of these settings, try increasingthe initial gain setting, and notice how the effect of the incoming control voltage isdecreased. What effect is being created here? CD track 44 Try increasing the rate and depth toproduce sidebands. CD track 454. Try experiment #3 again, but this time, use the exponential control input. What sounds differentabout the output now? Why is there almost no change in amplitude? Try using VCO-2’s pulseoutput instead of the sine output. Why is this more effective?5. Patch VCO-3’s saw wave to one of the audio inputs of the VCA, and this time, use the ADSRgenerator patched to the linear control input (redundant patch) to control the VCA. Repeat thisexperiment, and this time patch the AR generator to the exponential response circuit. What isdifferent about this sound? CD track 436. Create a patch in which VCO-2 and VCO-3’s saw waves are fed into the VCF. The VCF’s Fc shouldbe controlled by the ADSR generator. The VCF’s output should be fed to the VCA. Control theVCA using the AR generator. Notice how effective this patch is. Note which settings are themost beneficial on the AR generator regardless of the settings of the ADSR generator. Nowrepeat this experiment, and control the VCA using the ADSR generator and control the VCFusing the AR generator. Which of the two configurations do you prefer? CD track 467. Connect two different VCOs tuned to different pitches to each of the VCA’s audio inputs, anddemonstrate its ability as a mixer.8. Compare the VCF’s gating to the VCA’s gating by patching the saw wave from VCO-2 to the audioinputs of each, and bring up the outputs of the VCF and the VCA in turn at the mixer. Start withthe VCF, open the filter completely, with no resonance. Sweep the Fc down until the filter isclosed. Notice that as the sound got softer, the timbre of the sound changed as well. Next, listento the VCA perform the same gating task by starting with the INITIAL GAIN set full open andthen sweep it down until it is fully closed. Notice that the timbre of the sound remains constantthroughout the sweep, and only the amplitude or volume of the sound changes. CD track 429. Note what is normalled to each input of the VCA. Notice where the VCA’s output is normalled.