Show allYou said: ashdown bass envelopeThe Ashdown Bass Envelope Filter is a dynamic, auto-triggered filter pedal built specifically to give bass players expressive, auto-wah and funky, synth-like textures. Like most classic Ashdown Engineering gear, it is highly recognizable by its illuminated, signature VU input meter shielded by a protective metal roll bar. [1, 2, 3, 4, 5]Key Features and Tone ShapingThe pedal uses continuous control knobs rather than simple toggle switches, allowing you to finely blend your parameters:

• Up / Down Sweep: Instead of a fixed direction, a dedicated control knob lets you shift seamlessly between an upward sweep (low to high frequencies) or a downward sweep (high to low frequencies).
• BP / LP Filter Modes: Adjusts the behavior of the sweep between Band-Pass (classic, vocal auto-wah voice) and Low-Pass (darker, bass-heavy filtering). [1, 2, 3]
• Q / Peak Control: Sharpens the bandwidth ("Q") of the filter. Turning it up delivers much more aggressive, resonant, and "spaced-out" filter sweeps.
• Dynamic Response: The envelope is highly touch-sensitive, meaning the depth and opening of the filter are directly dictated by how hard you strike the strings.