Pittsburgh Modular Synthesizers: Voltage Lab 2 Utilities – A Patchable Powerhouse Unpacked

The sample and hold section is the first utility under the microscope, and it immediately demonstrates its dual role as both a modulation source and a noise generator. The noise output is showcased as a classic random voltage source, perfect for injecting unpredictability into a patch. By routing the sample and hold output into oscillator FM, the video illustrates how these random voltages can animate timbres in lively, unpredictable ways.

But the Voltage Lab 2 doesn’t stop at noise. The sample input can also accept more predictable sources, such as the sawtooth from oscillator two. This flexibility allows for stepped, rhythmic modulations that are tightly clocked, opening up a range of creative possibilities. The presence of both internal and external clocking options means users can sync or de-sync their modulations as the patch demands.

The effects section is where things get particularly interesting, with a ring modulator and bit crusher ready to mangle and reshape audio signals. The ring modulator takes sine waves from both oscillators, producing the classic metallic clang and complex sidebands that modular fans love. By swapping in different waveforms—such as squares or reflected shapes—the character of the ring mod shifts, adding harmonic grit and variation.

The bit crusher, meanwhile, is all about digital destruction. Feeding the ring mod’s output into the crusher yields a sound that’s described as both beautiful and clangy, with the ability to further tweak the input for subtle or extreme results. The video demonstrates how changing the source material—oscillator seeds or reflected waves—alters the crushed output, though not every tweak results in dramatic differences.

Throughout, the focus is on hands-on experimentation. The presenter isn’t afraid to push the effects hard, showing how these tools can be used for everything from subtle enhancement to outright sonic chaos. It’s a reminder that, in modular synthesis, the journey is often as rewarding as the destination.

Next up are the audio CV processors, which include an amplifier and an attenuverter—essential tools for controlling signal levels and polarity. The amplifier is shown boosting external signals, such as drum machine outputs, to levels suitable for further processing or envelope following. This is especially useful for integrating non-modular gear or shaping modulation sources.

The attenuverter offers both attenuation and polarity inversion, spanning from -5V to +4V. This makes it invaluable for dialing in the exact amount of modulation or for flipping a signal’s direction. The demonstration highlights how taking the attenuverter below zero can silence a signal, effectively acting as a voltage-controlled mute or even a pseudo-delay effect when modulated. The default routing from amplifier to attenuverter streamlines workflow, making these processors quick to patch and adjust.