Noise Tools collects and connects a number of practical modular synthesis utilities beneath a single 1U, 22 hp panel. Specifically, it contains:
Most people consider noise to be “undesirable,” and product developers expend great effort to design circuits that minimize noise. So why would anyone want to own Noise Tools — a module designed specifically to create noise?
Indeed, unwanted noise is undesirable. But not all noise is unwanted. Synthesizing the sound of wind or waves are a couple of the more obvious uses for a noise generator, but the possibilities go far beyond. The crack of a snare hit; the breathiness of a flute sound; an added sizzle to a resonant pad — all are within the sonic domain of noise.
But noise has many other benefits beyond simply being heard. Noise happens to make a wonderful modulator. When noise is used to modulate a filter’s cutoff frequency, or an oscillator’s pitch or pulse width, then all sorts of raspy, buzzy, gritty timbres are obtained.
Noise is also a key ingredient in sample & hold circuits, so one is included in Noise Tools. Sample & Hold (S&H) is a technique most commonly used to generate stepped, random voltages. The circuit works by (you guessed it) sampling an input signal’s voltage each time you send it a clock pulse, and holding that voltage until the next clock pulse. So, naturally, Noise Tools also contains the requisite clocking tools! Two of the most common destinations for the S&H output are a filter’s cutoff frequency (creating stepped, clocked timbral changes), and the VCO frequency (which produces random notes at clocked intervals).
Of course, you might not always want your voltages to change so abruptly at each clock pulse. Maybe you’d prefer they wobble about gradually and with more grace? To do that, you need a slew circuit, and once again Noise Tools has you covered. With all these features, plus the ability to create random pulses, clock to external pulses, perform more esoteric track & hold duties, and slew external voltages, Noise Tools far exceeds the capabilities suggested by its humble name or its tiny 1U form factor.