A fully analog modular synthesizer in the 5U format, designed for uncompromising sound quality and maximum flexibility. Inspired by the classics, built for the future.

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The East Coast VCO and the PPG Lowpass Filter is coming soon!

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EAST COAST VCO

The East Coast VCO is an analog performance oscillator for 5U modular systems —
compact, hands-on, and fully dotcom compatible for easy integration into existing
setups.

Its neo-vintage sound combines the character of classic late-1970s performance
oscillators with modern precision: stable tuning, powerful bass, and aggressive
sync sounds, while preserving the lively, organic character of analog synthesis.
With a foot range selector, interval control, pulse width modulation with CV
attenuation, and two pitch CV inputs, the East Coast VCO offers extensive control
for leads, sequencer lines, and complex patches.
An oscillator made to be played — not just patched.

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Technical Description – East Coast VCO
The East Coast VCO is an analog voltage-controlled oscillator (VCO) in 5U format,
designed for classic subtractive synthesis with extended functionality for modular
applications.

Frequency Control and Tuning
The oscillator frequency is primarily controlled via the 1V/octave CV input, enabling
accurate tracking over multiple octaves.

For direct control, the module provides:
• 5-position foot range rotary switch for selecting musical frequency ranges
• Pitch potentiometer for fine tuning
• Interval potentiometer for continuous detuning, ideal for intervals and beating effects

In addition, two independent pitch CV inputs (CV-1 and CV-2) are available, each
with its own attenuator. These allow flexible combination of multiple modulation
sources such as envelopes, LFOs, or sequencers.

Waveform Generation
The oscillator provides multiple classic waveforms simultaneously:

• Sawtooth (Saw)
• Rectangle (Rect)
• Triangle (Tri)
• Sine (Sine)

All waveforms are available in parallel at dedicated outputs and can be used
simultaneously.

Pulse Width Modulation (PWM)
The pulse wave width can be controlled both manually and via external control
voltage:

• Large rotary control for pulse width adjustment
• PWM CV input for external modulation
• PWM attenuator for controlling modulation depth

This enables both static timbres and dynamic modulation, for example via LFOs.

Synchronization (Sync)
The East Coast VCO features a hard sync input, allowing the oscillator to be reset
by an external signal.

This enables characteristic sync sounds with rich and aggressive harmonic content,
especially when combined with frequency modulation.
An additional sync output (square wave) allows the module to act as a master
oscillator in sync configurations.

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Connections
All audio and control voltage connections are implemented as 6.3 mm (1/4”) jacks,
compliant with the 5U/dotcom standard.

Inputs:
• 1V/octave CV
• CV-1 (with attenuator)
• CV-2 (with attenuator)
• PWM CV (with attenuator)
• Sync In

Outputs:
• Saw
• Rect
• Tri
• Sine
• Sync Out (Square)

Integration
The module is mechanically and electrically compatible with standard 5U systems in
dotcom format (±15V) and integrates seamlessly into existing setups.

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PPG LOWPASS FILTER

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This multi-functional module is a faithful recreation of the core signal processing
chain from the legendary 1975 PPG 1002 synthesizer. It combines an audio mixer, a
dedicated noise source, a classic 24dB lowpass filter, and a discrete VCA into a
single high-performance unit, capturing the unique sonic signature of early German
high-end synthesis.

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Mixer & Noise Section
The input stage allows for the blending of external signals with internal sound
sources before they hit the filter.

• Audio Inputs 1 & 2: Two dedicated inputs for processing external oscillators or other sound sources.
• Internal Noise Generator: A built-in analog noise source.
• Noise Level: Adjusts the amount of internal noise added to the filter input, perfect for adding grit, percussion textures, or atmospheric hiss.

24dB Lowpass Filter (VCF)
The heart of the module is the 24dB/octave lowpass filter, known for its precision
and distinct character.

• Cutoff: Sets the corner frequency of the filter.
• Character (Resonance): Controls the emphasis at the cutoff frequency.

Increasing this parameter moves the filter from subtle shaping into the
classic "ringing" PPG territory.
• VCF CV Inputs (1 & 2): Two inputs for external frequency modulation.
• CV Amount 1 & 2: Dedicated attenuators for the CV inputs, allowing for precise control over filter sweeps from envelopes or LFOs

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Discrete VCA Section
The signal is routed through a discrete VCA (Voltage Controlled Amplifier) circuit,
modeled exactly after the 1002 original.

• Gain: A manual control to open the VCA, allowing for continuous drones or calibration.
• CV-AMT (VCA): Adjusts the intensity of the external modulation acting on the VCA gain.
• VCA CV Input: Input for external control voltage (usually an envelope) to shape the volume contour.

Connectivity
• Audio In 1 & 2: Standard inputs for the mixer stage.
• VCF CV In 1 & 2: Control voltage inputs for the Cutoff frequency.
• VCA CV In: Control voltage input for the VCA gain.
• Output: The final processed signal, tapped after the VCA stage

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Technical Characteristics

The PPG "Sound"
Unlike the saturated ladder filters of its era, the PPG 24dB Lowpass is renowned
for its clarity and "Character." It remains musical even at high resonance settings,
providing a sharp, defined edge that made the 1002 a favorite for precise, cutting
lead sounds and deep, controlled basses.

Discrete Architecture
The VCA is built using a discrete design rather than standard modern ICs. This
preserves the subtle harmonic nuances and the specific "attack feel" of the 1975
original, ensuring that the module reacts dynamically to your envelope shapes.

Integration
The module is mechanically and electrically compatible with standard 5U systems in
dotcom format (±15V) and integrates seamlessly into existing setups.