PanVCA 4HP
Stereo VCA and Panner with attenuverter and offset
Buy Assembled [130€] » Buy PCBs [20€] »
PanVCA is two modules in one: a stereo VCA and a Panner, combined with an attenuverter knob for the CV signal, and a full range offset knob. The mode can be changed with a flip of the dedicated MODE switch. PanVCA is a spiritual successor to the Avalon Harmonics iVCA, significantly improving on its functionality but keeping the classic transistor circuit. Features a golden (ENIG coated) panel.
The L and R IN jacks are for audio input, while L and R OUT jacks are for the output. R IN jack is normalled to the L IN jack when nothing is plugged into it, allowing to expand a mono signal to stereo. Note that the audio output is AC coupled so it cannot be used for passing CV signals. The inputs have around 14 Vpp capacity. IN GAIN knob can be used to adjust the gain of the incoming audio signal and can be used to tame very loud signals if necessary. When set above around 3 o'clock, the signal will have some additional gain applied to it.
CV signal can be inserted into the CV jack in the middle. ATN knob allows for attenuverting the signal, making it possible to invert it, while OFS knob adds an offset voltage from -5V to +5V. These two knobs together create a CV mix, which has a different use depending on the mode that the module is in.
In VCA mode, the module is a stereo VCA so both left and right CV are coupled together. At +5V CV, ATN set all the way clockwise, and IN GAIN knob set at 3 o'clock, output will be at unity gain. The CV mix can however exceed the 5V (either by adding offset to the CV signal, or by applying a higher signal), allowing for up to 2x volume on output. Thanks to the versatility of ATN and OFS knobs, the module can behave like a normal VCA, or as an inverted VCA, allowing for easy trance gate effects and more.
In PAN mode, left and right channels are fully open by default, while left and right CV are inverted from each other. At +5V, left channel is silent, while right is at 2x output. At -5V, left channel is at 2x output, while right is silent. CV input, combined with ATN knob can be used to automate panning of the signal left/right and adjust the intensity of the effect, best used with an LFO. OFS knob acts as a simple manual panning knob. Because it is a fully analog circuit, the panning can be driven at audio rates creating interesting and wild effects.
Near the CV input, a bipolar LED shows the status of the overall CV mix of ATN and OFS knobs. Green represents positive values, while red represents negative values. Two orange LEDs on top signify the status of the left and right VCAs, allowing for easy monitoring of their states in both VCA and PAN modes.
Interactive BOMs
DISCLAIMER: Interactive BOMs don't have all of the info on them and are only for placement reference. Please download the full BOM sheet above when assembling.
Features
Two modules in one: VCA and Panner
Compact 4 HP design
Input gain knob with some extra gain
CV attenuverter and full range offset knobs
VCAs fully open with +5V CV
Status LEDs for CV and status of VCAs
Wrong polarity protection
Skiff friendly
Size: 4HP
Depth: 25mm
Power: +12V: 31mA, -12V: 28mA