The BSRI Geometry Stacks is an analog flanger that feels less like an effect and more like a piece of malfunctioning space station equipment.
The designer grew up on hard sci-fi he didn’t fully understand. But the feeling stuck. The math. The physics. The sense that there were doors in the universe you weren’t supposed to open. So he built a pedal that opens them anyway.
This thing runs on bucket brigade chips. Obsolete technology. Little capacitors shuffling your signal along like data on a dying tape reel. It’s the same stuff that made old flangers sound like they were falling through a hole in reality. This one just has more knobs to help you fall faster.
What you get is modulation that can be delicate and subtle or mechanical and extreme. A gentle whoosh behind your chords, or a full-scale warp drive malfunction. It extends spacetime on the fly. Then lets you snap back at the click of a switch.
Here’s what the knobs do:
- Level: How much of the modulated signal bleeds into your dry sound. Subtle shimmer or total immersion.
- Polarity toggle: Down gives you classic in-phase flanging. That jet swoosh. Up flips it out of phase for a hollow, tubular sound. Like your amp is playing through a concrete pipe.
- Velocity: Modulation speed. From slow drift to frantic wobble.
- Width: How far the sweep travels. Narrow for focused movement. Wide for full-on chaos. At max, the delay knob stops mattering because everything is turning.
- Voice: Treble boost or cut. Brighten the edge or bury it in fog.
- Enhance: Regeneration. Feedback. How much signal gets sent back through the bucket brigade. Low settings are rich. High settings start to scream. Self-oscillation. The pedal eating itself. Be careful. It gets loud at extremes.
- Delay: Sets the center point for the modulation. At minimum width, this becomes a manual sweep control. You can park the flanger at one spot and let it hang there like a bad memory.
- Activate: True bypass footswitch. On. Off. Clean.
- Extend: The secret weapon. Taps an additional bucket brigade chip into the circuit. Longer delays. Wilder sweeps. Deeper, stranger flanging. Flick this and the pedal shifts dimensions.
Play with it. Explore. You will be rewarded. And keep an eye on that Enhance knob. It bites when you’re not looking.
