Delay, Chorus, and Flanger
Watch REAPER Mania’s Why and How to Use Delay and Creating Sends alongside this lesson. If you want to explore the other effects, watch Chorus & Flange FX .
Delay is one of the simplest and most powerful time-based effects in audio production. It records an incoming signal, waits for a set amount of time, and then plays it back—either once or many times, depending on the settings.
By mixing delayed and dry signals, delay creates space, rhythm, width, and unique timbral textures. REAPER’s ReaDelay plugin makes it easy to explore these variations.
Understanding Delay
A delay effect:
- Records the input into a short digital buffer.
- Plays it back after a defined delay time.
- Mixes that delayed signal with the dry (original) one.
By adjusting delay time, feedback, and mix, you can shape the character and movement of the sound.
Delay Time Ranges and Their Effects
| Delay Type | Typical Range (ms) | Sound Character | Tempo-Synced Equivalents (at 120 BPM) |
|---|---|---|---|
| Very short | 1–10 | Comb filtering; flanging zone | Usually set in milliseconds |
| Short (ADT/Haas) | 10–40 | Thickening, width; watch mono compatibility | — |
| Slapback | 75–150 | Single audible echo; classic rockabilly vocal feel | 1/16 ≈ 125 ms |
| Rhythmic/long | 250–800+ | Distinct rhythmic repeats; ambient/spatial echoes | 1/8 = 250 ms; dotted-1/8 = 375 ms; 1/4 = 500 ms |
| Very long | 800+ | Sound design; evolving textures; looping | — |
Formula for Delay Time:delay (ms) = 60000 / BPM × number_of_quarter_notes
Use 1 for a quarter note, 0.5 for an eighth, and 0.75 for a dotted eighth. At 120 BPM, a dotted eighth is 375 ms. At Project 3’s 96 BPM, an eighth is 312.5 ms and a quarter is 625 ms.
Optional listening examples
Rhythmic and Long Delays
U2 – Where the Streets Have No Name
The Edge’s dotted-eighth delay defines U2’s signature rhythmic guitar sound.
Pink Floyd – Run Like Hell
A tempo-synced delay that locks perfectly with the groove.
Slapback Delay
Elvis Presley – Mystery Train
Classic Sun Studios slapback—around 130 ms, minimal feedback.
John Lennon – Instant Karma!
Short single echo for added vocal presence.
Doubling / ADT
The Beatles – Tomorrow Never Knows
Subtle, modulated short delays create doubled textures.
Nirvana – Smells Like Teen Spirit
Vocal thickness comes from double-tracking and short delay blending.
Ping-Pong / Stereo Delay
David Bowie – Let’s Dance
Stereo delays bounce between left and right for width and energy.
Flanger
Small Faces – Itchycoo Park
One of the earliest examples of tape flanging.
Van Halen – Unchained
Jet-like flanger sweep across Eddie Van Halen’s guitar.
Chorus
Nirvana – Come As You Are
Watery chorus modulation on the guitar riff.
The Police – Walking on the Moon
Chorus and delay combine for lush, atmospheric space.
Project 3 delay exercise
Goal: Explore how different delay times affect perception and space.
- Open your Project 3 working session. Preserve the static balance you saved before adding processing. If you need separate practice audio, use these files .
- Create one track named Delay Return, outside the instrument folders.
- Insert ReaDelay. Set Wet to 0 dB and Dry to -inf dB so only the delayed signal is heard on the return.
- Create a post-fader send from a vocal or chord instrument to the return. Begin with the send at -inf dB, then raise it gradually.
- Compare two settings on the same return, such as slapback around 120–150 ms and a longer tempo-synced eighth- or quarter-note echo. Adjust feedback as well as delay time. Mute the return to check whether the effect supports the full mix.
- Keep the setting that serves the song and note what you heard in both versions. Additional returns, filtering, and ducking are optional.
Optional: beyond basic delay
Both flanger and chorus are based on short modulated delays, but they differ in delay times, modulation depth, and the way they shape tone and movement.
| Effect | Typical Delay Time | Core Concept | Audible Character |
|---|---|---|---|
| Flanger | 0.5–10 ms | Mixes the dry signal with a very short, modulated delay. The constantly changing time offset causes moving comb-filter peaks in the frequency spectrum. | Sweeping, “jet plane” or “whooshing” sound as frequencies phase in and out. |
| Chorus | 15–30 ms | Mixes the dry signal with one or more slightly longer, modulated delays. These delays simulate small timing/pitch variations between performers. | Smooth, shimmering thickening effect—like multiple instruments playing together. |
Flanger in REAPER
Try JS: Flanger. Listen as you adjust its delay, feedback, and modulation controls. Compare it with the dry track at similar loudness.
Chorus in REAPER
Use REAPER’s built-in Chorus or JS: Chorus:
- Delay: 20–30 ms
- Mod Rate: 0.3–0.6 Hz
- Depth: 5–10 ms modulation
Optional: creative delay techniques
Ping-Pong Delay
- Two taps in ReaDelay, panned left/right with slightly different times.
Ducked Delay
- Sidechain a compressor (ReaComp) from the dry signal to make delay audible only between phrases.
Feedback Loop Sound Design
- Enable feedback routing (Project Settings → Advanced).
Add EQ or distortion in the loop for evolving textures. Always use a limiter.
Karplus–Strong Plucked Delay
- Delay: 8–12 ms
- High feedback, lowpass filter
- Excite with a short noise burst.