How To Read Patch Diagrams

A sine wave can be produced by a sine wave oscillator, but also by function generators, as you will see below. A sine wave is a pure, smooth cyclical waveform with no harmonic content beyond the fundamental frequency. In Studio 1 this is most often generated by the Rohde & Schwarz oscillators or the HP function generators.

A waveform that switches abruptly between two voltage levels. When the on/off time is equal it is a square wave; when the duty cycle varies it is a pulse. Rich in odd harmonics, it produces a hollow, buzzy tone. Widely used as a clock signal to trigger other modules in a rhythmic sequence.

A function generator can output a various waveforms depending on the exact model. At times it will be referred to by using a sine or pulse symbol. When the FG symbol is used it means the exact waveform is not crucial to the patch and may vary. In Studio 1, 4 different types of function generator can be found, 10 units in total.

A noise output is a random voltage signal containing energy across a broad frequency range. White noise distributes energy equally per hertz; pink noise distributes it equally per octave. In many Studio 1 patches noise is the primary sound source, shaped by filters into tonal or textural results.

A pulse generator is designed to generate pulses with adjustable timing parameters. It provides independent control over pulse width, repetition rate, amplitude, and delay, enabling accurate configuration of signals. The unit supports both internal triggering and external trigger inputs, allowing synchronization with other instruments.

A word generator outputs a programmable binary sequence as voltage pulses. It is often used as a sort of step sequencer: each "word" is a short repeating pattern of on/off pulses. By using the same clock input on multiple word generators intricate rhythms and beats can be composed.

A narrow bandpass filter that passes only a selected range of frequencies while attenuating everything else. The "Q" knob controls bandwidth: a high Q gives a narrow, resonant peak, and a low Q gives a broader, gentler contour. The selective amplifier is always referred to as BPF in patch diagrams. When recreating a patch any BPF can be used, if not specified otherwise.

A bandpass filter can be tuned to isolate a specific range of frequencies around a chosen center frequency.

The passive bandpass filter divides audio into octave-wide frequency bands. Each bandpass section allows frequencies within a specific range to pass through while attenuating frequencies outside that range.

A bank of bandpass filters spaced one third of an octave apart across the full audible spectrum. On the HP 8058A unit, each band has an individual output, allowing a single input signal to be split into separate frequency components. In some patches, individual bands are often fed back into each other to create complex resonant structures. In studio 1 there are two 1/3 octave filters.

The boxcar integrator is a gated signal processor that averages input signals over defined time windows, effectively isolating specific portions of a waveform. It can produce smoothed or pulsed audio outputs, emphasizing rhythmic elements or creating unique textures from otherwise noisy or transient signals.

The lock-in amplifier/phase detector extracts small AC signals from noisy environments using phase-sensitive detection. It can transform input signals into unusual audio outputs, often producing strange tones, rhythmic pulses, and unpredictable distortion. This also makes it useful for experimental sound design and creating textures.

The ring modulator allows an input signal to be multiplied by a second signal, in this case a sine wave. This process generates overtones, which can give the sound a metallic character. The multiplier is also often used as a ring modulator. When RM is specified, a patch uses the ring modulator connected to the main mixer.

The multiplier is a signal processor that performs real-time multiplication or division of input signals. It can be used to combine or modulate signals, enabling applications such as amplitude modulation, frequency scaling, or complex signal synthesis. It is mostly used in its multiplication mode, where two signals are multiplied (ringmodulation).

The spring reverb in studio 1 is patched to the main mixer and can be used by sending a signal through aux channels 5 and 6 to the reverb. The spring reverb is a physical unit that can be used to simulate space, but also for resonant sound-shaping within feedback patches.

The wave analyser can function as a standalone narrowband measurement system, isolating and measuring specific frequency components with high precision. Combined with the sweeping local oscillator unit, it allows both static spectral analysis and dynamic frequency filtering, making it useful for extracting, emphasizing, or reconstructing complex audio signals.

The EG&G model 175 is a signal generator and timing controller for automated testing. It produces voltage pulse sequences with programmable timing and amplitude, allowing it to control or trigger other modules.

Any signal used to change a parameter rather than be heard directly. CV lines can, for example, connect an LFO, envelope, or programmer output to the frequency, gain, or filter cutoff input of another module.

A gate input receives a control signal used to trigger or activate a function rather than be heard directly. Gate signals can, for example, trigger an envelope, start a sequencer step, or switch another module on and off.

A trigger input receives a short control signal used to initiate an event rather than be heard directly. Trigger signals can, for example, start an envelope, fire a single drum sound, or advance a sequencer step.

A filled dot on a line indicates that one signal is being sent to two or more destinations simultaneously. For example, a single oscillator can simultaneously provide audio to a filter and a control voltage to a ring modulator. The FG control unit and custom 16-channel VCA both include multiples, where one input can be split into multiple outputs. In Studio 1, there are also BNC cable splitters that can be attached anywhere.

The mixer icon marks where the final audio signal leaves the patch and goes to speakers or a recording device. Some patches have multiple mixer points labelled, which means that the audio goes through a submixer before going to the the final mixer.