ARP2600 - Fundamentals of Music Technology - Cyborgstudio.com

116 - SECTION FOURTEEN: PATCH DIAGRAMMING AND ANALYSISAbove and beyond all of this, the keyboard’s LFO is elbowing into the picture, adding some vibrato ata slow speed. There will be a long delay between the time the key is pressed and the time this vibratobecomes apparent, however.The VCA’s gain is being modulated by the AR generator, which is set for a very short attack andrelease. These settings are mirrored in the ADSR generator, which is controlling the VCF. It seems thatthis patch is going to consist of short bursts of sound as the EG’s momentarily open and close both theVCF and VCA.VCF appears to have another source controlling it’s cutoff, however. This patch comes from the lagprocessor, whose slider is set to about 1/3 open, which translates to about 1 second of lag, perhaps a bitmore. The lag processor’s input has the envelope follower normalled to it. The envelope follower hasits level raised this time, and the preamp has been patched to its input. This is a redundant patch, andshould throw up a red flag for test-taking purposes that someone is going to great trouble to convincethe reader that this patch is authentic. In this particular patch, there is even a level set on the preamp,although nothing is connected to it, so all in all, it is just one very long dead end. This brings up animportant point: If something is not drawn on a patch sheet, do not assume it is there.STEP THREEIn this patch, there is very little left to examine, but the patch deserves looking over one more time.Upon closer inspection, one can see that the S/H GATE switch has been moved to its lower position, sothat the keyboard will no longer trigger the EGs and now the internal clock will cause the EGs to fire.This makes sense, because the clock is going at a fairly fast rate, and a long attack or release timewouldn’t have much effect on the VCA and VCF, so they had to be kept short. Many times, differentparts of a patch will reinforce each other and make it obvious that the reader is on the right track. Ifthings seem to conflict or contradict each other, stop and question the authenticity of each signal beingfollowed.One final item is the resonance level on the VCF. Normally, this could help to create a filter sweepsound, but the filter is going to be opening and closing too quickly to perceive an actual sweep. Instead,this level of resonance will produce a rather bubbly, rounded tone.SUMMING UP PATCH TWOIf one was asked to describe the sound of patch two, one might say that patch two is a duophonic patchwith a sawtooth timbre with some noise and a bit of the high-frequency ring modulation peekingthrough. The pitch will continually rise and fall, but will do so in steps rather than a continuous smearin frequency. If the keyboard is played, vibrato will be introduced after a few moments, but the internalclock is causing the EGs to fire in short bursts, which are rather ‘burbly’ because of the resonance.Finally, the sound pulses on and off in time with the S/H module because the electronic switch isswitching between the patch and silence. This sound can be heard on CD track 82. Again, if anythingseems unfamiliar or unclear about the explanation of this patch, take a few moments to go back into theappropriate section to review.