Keeley RK2000 Funk Siren Delay Pedal - Studio Gray

Designed to capture one of the most recognizable delay sounds in modern improvisational guitar playing, the Keeley Electronics RK2000 Funk Siren Delay pedal brings the signature effect popularized by Trey Anastasio of Phish into a compact, performance-ready guitar delay pedal. Originally achieved using an early-’80s rackmount digital delay, this sound is built around short delay loops, expressive modulation and real-time manipulation. The RK2000 recreates that approach with a 12-bit digital delay engine, integrated Hold function for phrase looping and multi-octave modulation for pitch-based movement. With stereo operation, tap tempo, onboard presets, MIDI integration and expression control, it delivers both the character of its rackmount inspiration and the flexibility required for modern pedalboards. From layered improvisation to ambient textures and rhythmic delay patterns, this Keeley delay pedal provides a focused platform for time-based creativity in live and studio environments.

Funk Siren Delay Concept and Phrase Looping Workflow

At the heart of the RK2000 is the “funk siren” delay technique closely associated with Trey Anastasio’s playing, where a short delay is used to capture a repeating phrase that becomes the foundation for improvisation. By engaging the Hold function, players can sustain a looped phrase and layer additional lines on top in real time. Unlike traditional loopers, this approach retains the tonal character and movement of the delay signal, allowing modulation and filtering to shape the loop as it evolves. The result is a hybrid workflow that blends delay and phrase looping into a single, performance-driven effect suited for improvisational playing styles.

12-Bit Delay Engine With Extended Time and Texture

The pedal’s 12-bit digital delay engine recreates the tonal character of early rackmount units, balancing clarity with a slightly grainy, textured repeat profile. With up to 1,023 milliseconds of delay time, it covers everything from tight doubling and slapback to extended rhythmic echoes. This architecture allows the repeats to sit naturally in a mix while maintaining enough character to remain distinct. When paired with the Hold function, the delay becomes a tool for building layered phrases and ambient textures, extending its role beyond traditional delay applications.

Modulation, Tone Shaping and Dynamic Control

Modulation is central to the RK2000’s sound, offering pitch-based movement that spans multiple octaves. Depth and rate controls allow adjustment from subtle chorus-like motion to more aggressive pitch-shifted sweeps. A dedicated filter control shapes the tonal character of repeats, from darker, tape-style echoes to brighter, more defined delay lines. The input gain control adds saturation to the signal, introducing tape-like compression and harmonic content to repeats. Together, these controls provide detailed command over both the tonal and dynamic behavior of the delay.

Stereo Operation, MIDI Integration and Performance Control

With stereo inputs and outputs, the pedal supports wide delay imaging for modern rigs, including ping-pong and spatial effects. Tap tempo with selectable subdivisions ensures delay timing remains locked to performance tempo. Five onboard presets provide immediate access to core sounds, while MIDI support expands this to up to 127 recallable presets for more complex setups. Expression and remote inputs enable real-time control over key parameters such as delay time, feedback and modulation, making the pedal adaptable for both hands-on players and integrated rig environments.

Vintage-Inspired Delay for Improvisational and Ambient Players

Combining a 12-bit delay architecture with phrase looping, multi-octave modulation and modern control integration, this pedal bridges the gap between vintage rack effects and contemporary pedalboard workflows. Its ability to function as both a delay and a looping tool makes it particularly well suited for players focused on improvisation, ambient textures and evolving rhythmic patterns. With flexible routing, expanded control options and a distinctive tonal identity, the Keeley Electronics RK2000 Funk Siren Delay delivers a focused and expressive approach to time-based effects.

Keeley Electronics RK2000 Funk Siren Delay Pedal: FAQ

What is the RK2000 Funk Siren Delay based on?
It is based on the delay technique popularized by Trey Anastasio of Phish, originally created using an early-’80s rackmount digital delay to loop short phrases for real-time improvisation.

What does the Funk Siren effect do?
It captures a repeating delay phrase and allows you to layer additional playing over it while shaping the sound with modulation and filtering.

Can this pedal be used as a looper?
Yes, the Hold function allows you to capture and sustain delay phrases for layered improvisation.

Does the pedal support stereo setups?
Yes, it includes stereo inputs and outputs for wider delay imaging and spatial effects.

Is MIDI required to use this pedal?
No, it works as a standalone delay pedal, but MIDI expands preset control and parameter access.