The VCA IV is a high-density, four-channel voltage-controlled amplifier designed for precision signal shaping and high-fidelity mixing. Blending the performance of a professional utility with smart normalization features, it serves as a central hub for managing both audio and CV paths in your system.

Versatile Quad Architecture & Stereo Pairing
Fundamentally designed as four individual, high-quality OTA-based VCAs, each channel features its own signal input, CV input, and dedicated manual Offset control.

Beyond independent quad operation, the module features intelligent internal normalization to seamlessly handle stereo signals:

• Stereo Signal Normalization: Input 1 is normalled to Input 2 via a switched jack (and Input 3 to 4). Patching a mono signal into Input 1 automatically splits it to Input 2 for effortless parallel processing or dual-mono setups.

• Dual-CV Normalization: CV 1 is normalled to CV 2 (and CV 3 to 4). This allows a single CV source—such as an envelope or LFO—to control both channels in the stereo pair simultaneously, keeping your stereo image perfectly in sync.

• Precision Balancing: Even when sharing a CV source, each channel's manual Offset knob remains fully independent, allowing you to fine-tune the absolute balance or shift the center of your stereo image.

Voltage-Controlled Mixing & Signal Routing
All four channels are routed to a low-noise summing circuit at the Mix Out, allowing the VCA IV to function as a compact voltage-controlled mixer.

Switched Outputs: Patching a cable into any individual VCA channel output automatically breaks the normalization and removes that specific channel from the master Mix Out stream.

Availability & Build Features
The VCA IV is available both as a fully completed, ready-to-patch module and as a builder-friendly DIY project:

• Fully Assembled: Professionally built, fully tested, and ready to install into your system right out of the box.

• DIY Kit Experience: Perfect for builders of all skill levels. All tiny, complex surface-mount (SMD) components come pre-soldered from the factory. You only need to solder the premium through-hole (THT) mechanical parts (jacks, potentiometers, and power socket).

• Zero Calibration: For DIYers, the circuit is engineered entirely for "plug-and-play" use. No trimming, tuning, or multimeters are required after assembly.

• Premium Aesthetic: Both versions feature our signature matte-black front panel, crisp white iconography, and stunning gold-plated copper (ENIG) artwork.

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