Old Blood Noise Endeavors BL-37 Reverb

A "variable-clock" reverb in the lineage of OBNE's BL pedals

The BL-37 belongs to Old Blood Noise Endeavors' BL series, recognizable by its large central slider. Here, the idea is not to replicate a specific vintage reverb but to explore a modulated reverb whose "timing" can be freely manipulated. The result: spatialization that can remain fairly realistic and short, then shift to stretched tails, darker and intentionally degraded, with a constant sense of movement.

Who is it for, which styles, and in what contexts?

The BL-37 is aimed at guitarists (and bassists) seeking an inspiring reverb that's easy to dial in but capable of venturing off the beaten path. It shines in ambient, shoegaze, post-rock, indie, experimental rock environments, but can also add subtle depth to more classic parts.

In the studio, it becomes a sound design tool to broaden a riff, texture a melody, or give identity to a take. Live, its tactile approach (the "Clock" slider) is perfect for evolving the space between verse and chorus or transforming an ending into an expansive wash, all without menus or sub-functions.

Settings, controls, and design: simple yet remarkably expressive

The BL-37 gets straight to the point with four main controls. The Clock slider governs the system's "speed": depending on its position, you move from a short, snappy, and more faithful reverb to a longer, darker reverb with a more pronounced Lo-Fi grain. The Feedback knob adjusts the intensity and length of the reverb tails while emphasizing the modulation character.

The Mix control sets the Wet/Dry balance to place the effect in the background or bring it to the forefront. Finally, the Volume adjusts the overall output level, handy for compensating a high Mix setting or maintaining a consistent level when extending the reverb. Activation is via a silent soft-touch footswitch, designed for discreet switching on stage.

Sound signature

The BL-37's signature is its moving reverb: built-in modulation that gives a "living" quality, with undulations and a drifting sensation in the tails. At a high Clock setting, you get a short, highly reflective reverb, ideal for simulating a small room and adding definition to rhythmic playing. Lowering the Clock darkens and stretches the texture: the reverb becomes more dreamy, more blurred, sometimes almost "de-resolved," perfect for drones, open chords, and atmospheric leads.

The dynamics remain very usable: the pedal can stay subtle and musical with a moderate Mix or become a true Lo-Fi space generator when pushing Feedback and exploring the extremes of the Clock. It's exactly the kind of reverb that inspires different playing styles, letting notes breathe and sculpting the attack.

Technical specifications

Effects	Reverb	Type	sector
Technology	Digital	Use	electric guitar
Format	Pedal	Color	Multicolor

"Variable-Clock Effector " concept	timing control via Clock slider	Output	6.35mm Jack
Clock (slider)	influences fidelity/texture, perceived length, and modulation speed	Configuration	mono
Feedback	adjusts reverb intensity and tail length	Dimensions	120 x 66 x 58 mm
Mix	Wet/Dry balance control	Weight	300 g
Volume	overall output level	Required power supply	9V DC center negative (2.1 mm DC jack)
Bypass	true bypass	Current consumption	110 mA
Input	6.35mm Jack	Power adapter	not included