Thanks to Dr. Victor Lazzarini, I now have a working copy of Music V in my possession. I tinkered with it all weekend to get a better understanding of the system, temporarily frying my brain in the process.
In Csound, the sampling rate is determined in the header of the orchestra, and can be overridden with a command-line flag. In Music V, the sampling rate is hard-wired into the Fortran code.
The version of Music V provided to me uses a rate of 44.1kHz. I created a modified version to run at 20kHz to coincide with sampling rate specified in The Technology of Computer Music. (Mathews, pg. 43) Had to get my hands a little dirty with the Fortran code, though the procedure turned out to be easier than expected — just replaced all instances of 44100 with 20000.
Sampling rate alone doesn’t paint the full picture, as there is also the control rate to consider. Csound fully supports control rates, signals of a usually lower sampling rate used to control / modulate other unit-generators.
Back in the day when computers were *really* slow, and real-time performable digital synths were more fantasy than reality, rendering a short piece of music could take hours. To help reduce this time, control signals were introduced to greatly reduce the number of required computations.
Today, using a secondary lower sampling rate to control aspects of a digital synth engine or DSP is standard practice. In live situations, control rates allow musicians to run more effects and instruments at any given time than would be possible if everything was computed at the audio rate. So there is great reason why software like Reaktor fully embraces this older, yet highly effective concept.
Unfortunately for Music V, there is no such thing as a control rate.
In the preface of Csound manual, Barry Vercoe briefly describes how control rates came to be in Csound:
With Music 11 (1973) I took a different tack: the two distinct networks of control and audio signal processing stemmed from my intensive involvement in the preceding years in hardware synthesizer concepts and design. This division has been retained in Csound.