BJF VCF Filter Autowah

BJFE VCF (Voltage Controlled Filter)

The BJFE VCF was originally designed in 1991 as a remote wah for a rock guitarist’s rack system. The circuit was developed using a P-90 equipped Les Paul Special and later became the foundation for what would eventually evolve into the well-known Snow White Auto Wah.

While related to the Snow White Auto Wah, the VCF has its own character. It responds faster and delivers a uniquely soft, textured filter sound that feels extremely musical under the fingers. The result is a highly expressive filter effect that reacts naturally to your playing dynamics.

The VCF can produce everything from subtle envelope movement and vocal-like wah tones to sharper, more pronounced filter sweeps. Its responsive design makes it equally suitable for rhythm work, funk-style playing, and experimental filter textures.

Controls

• Decay – Adjusts the length of the filter sweep.
• Bias – Sets the center frequency of the filter.
• Res – Controls the resonance of the filter for sharper or smoother peaks.
• Sens – Adjusts the sensitivity of the filter response to your playing dynamics.

Power

• 9V battery
• Standard 2.1 mm center-negative DC 9V adapter

Specifications

• Type: Auto Wah / Envelope Filter
• Controls: Decay, Bias, Res, Sens
• Power: 9V battery or center-negative DC adapter

The BJFE VCF delivers a responsive, organic filter effect with a character all its own—fast, expressive, and rich with texture.