Learn the true meaning of the word “analog” and other ‘70s arcana.
synthesizers, real and emulated, are enjoying renewed popularity today.
Indeed, analog devices of all types might be more numerous now than they
were during the heyday of ARP, Moog, and Buchla. At the dawn of the 21st
century, there is steady demand for the technologies of yesteryear. This
article will help you understand some basic analog-synthesis concepts
and introduce you to some of the key features of analog synthesizers.
Then youll be able to better evaluate the analog and pseudoanalog
products flooding music stores.
The fluctuating voltage at the mic output is a signal, not a sound. The signal is an electronic representation, or analog, of the original sound. Thats all the word analog meanstheres no mystery to it.
Whether it originates in a mic or electronic circuitry, an analog signal represents sound directly and continuously. The voltage does not move in discrete steps from one level to another; it flows smoothly in an infinite continuum of voltage levels. In the analog universe, even stepped waveforms such as square waves move continuously. A square waves leading and trailing edges arent truly square. Examine a square wave closely on an oscilloscope, and youll see slightly rounded edges, because the voltage takes a finite time to rise and fall. No physical oscillator can achieve the infinitesimal rise time of the ideal square wave.
Analog signals have two key properties: (1) they are continuous, and (2) their parametersfrequency, amplitude, and phaseare continuously (and infinitely) variable. These properties make analog-synthesizer signals profoundly different from digital synthesizer signals. By definition, digital synths represent signals as numbers. Digital signals are quantized into a finite number of discrete steps, and there are no levels between steps. Likewise, parameter values on a digital synthesizer are quantized into a finite number of steps. Smaller step sizes give a digital synthesizer higher resolution; the higher the resolution, the better the synth can approximate the infinite resolution of analog devices.