The BOSS BF-3 Flanger provides thick, sweeping modulation textures using digital processing, optimized with dedicated input modes for both electric guitar and bass.Circuit & Performance Architecture

• Topology: Digital processing architecture.
• Bypass Behavior: Buffered bypass switching.
• Tap Tempo Function: Built-in tap tempo allows manual synchronisation of the modulation rate. Press and hold the footswitch for more than 2 seconds to enter tap tempo mode, then tap to the beat.

Control Layout & Functions

• RES / MANUAL (Dual Concentric Knob):
• • MANUAL (Outer Ring): Adjusts the center frequency where the flanging effect cuts in.
  • RES (Inner Knob): Controls the amount of resonance (feedback), deepening the jet-stream intensity.
• DEPTH: Regulates the sweep range of the modulation.
• RATE: Sets the speed of the flanging modulation cycle.
• MODE: Rotates through four specific digital voicings:
• • ULTRA: Delivers a heavy, exaggerated flanging effect with maximum depth.
  • STANDARD: Recreates the classic, traditional analog flanging effect.
  • GATE/PAN: Swirls the effect across a stereo image or applies rhythmic gating to the texture.
  • MOMENTARY: Engages the flanging effect only while the footswitch is held down.

Technical Specifications

• Power Requirements: 9V DC using a BOSS PSA-series adapter (center-negative polarity) or a standard 9V battery.
• Current Draw: 40 mA.
• Input/Output Array:
• • GUITAR IN: Standard high-impedance input for electric guitar.
  • BASS IN: Optimized frequency response input for bass guitars.
  • OUTPUT A (MONO) & OUTPUT B: Allows dual-amplifier stereo configurations or discrete panning/gating routines.
• Manufacturing Location: Engineered by BOSS Corporation (Roland) and manufactured in Taiwan (as shown on the base label in the final photo).