Introduction: Understanding Time-Based Effects
Time-based effects are essential tools in audio mixing that add dimension, space, and texture to recordings. Reverb, delay, and chorus are among the most commonly used time-based effects that can transform a flat, one-dimensional mix into a rich, three-dimensional sonic landscape. Understanding how these effects work and when to use them is crucial for creating professional-sounding mixes.
Reverb: Creating Space and Ambience
What Is Reverb?
Reverb (short for reverberation) is the persistence of sound after the original sound has stopped. It’s created when sound waves bounce off surfaces in an environment, creating thousands of reflections that gradually decay over time. In audio mixing, reverb simulates these natural acoustic spaces or creates entirely new ones.
Key Reverb Parameters
| Parameter | Function | Typical Range | Effect on Sound |
|---|---|---|---|
| Pre-delay | Time before reverb begins | 0-150ms | Longer values create separation between direct sound and reverb |
| Decay/RT60 | How long reverb takes to fade away | 0.1-10+ seconds | Defines perceived room size |
| Early Reflections | Initial distinct reflections | 0-50ms | Creates sense of room boundaries |
| Diffusion | Density of reflections | 0-100% | Higher values create smoother reverb |
| Damping | High frequency absorption | 0-100% | Higher values make reverb darker as it decays |
| Room Size | Virtual room dimensions | Varies by plugin | Affects character of reverb |
| Mix/Wet-Dry | Balance between processed and unprocessed signal | 0-100% | Controls overall reverb amount |
Types of Reverb
Room Reverb
- Characteristics: Short, tight, with pronounced early reflections
- Decay Time: 0.2-1.0 seconds
- Best For: Drums, percussion, acoustic instruments
- Sound Quality: Natural, subtle ambience
- Practical Tip: Use when you want instruments to sound like they’re in a real room without obvious reverb
Chamber Reverb
- Characteristics: Warm, diffuse, controlled decay
- Decay Time: 0.6-1.5 seconds
- Best For: Vocals, strings, horn sections
- Sound Quality: Smooth, musical, vintage character
- Practical Tip: Great for adding body and dimension without washing out details
Hall Reverb
- Characteristics: Large, smooth, long decay
- Decay Time: 1.5-5+ seconds
- Best For: Orchestra, cinematic elements, pads
- Sound Quality: Grand, spacious, lush
- Practical Tip: Use pre-delay (30-100ms) to maintain clarity with longer decays
Plate Reverb
- Characteristics: Bright, dense, distinctive character
- Decay Time: 0.5-2.5 seconds
- Best For: Vocals, snare drums, pianos
- Sound Quality: Metallic sheen, rich sustain
- Practical Tip: Often benefits from high-frequency dampening to tame brightness
Spring Reverb
- Characteristics: Bouncy, quirky, characterful
- Decay Time: 0.5-3.0 seconds
- Best For: Guitar, vintage effects, creative applications
- Sound Quality: Distinctive “boing,” retro character
- Practical Tip: Adds vintage character; embrace its imperfections
Non-Linear/Gated Reverb
- Characteristics: Unnatural decay, abrupt cutoff
- Decay Time: Varies, often short
- Best For: 80s-style drums, special effects
- Sound Quality: Artificial, dramatic, effect-oriented
- Practical Tip: Great for creating distinctive reverb effects that don’t wash out the mix
Practical Reverb Mixing Tips
- Use sends rather than inserts: Place reverb on aux tracks so multiple instruments can use the same reverb space
- EQ your reverb returns: High-pass around 200-300Hz to reduce mud, low-pass around 8-10kHz to reduce harshness
- Multiple reverbs: Use 2-3 different reverbs in a mix (short, medium, long) rather than many different types
- Reverb and positioning: Less reverb = closer to listener, more reverb = further away
- Automate reverb: Increase reverb amount in sparse sections, reduce in busy parts
- Pre-delay for clarity: Use 20-80ms pre-delay to maintain definition while still adding space
Delay: Creating Echo and Rhythmic Effects
What Is Delay?
Delay is an effect that records an input signal and plays it back after a specified time period. Unlike reverb (which consists of thousands of reflections), delay typically creates distinct, discrete repetitions of the original sound.
Key Delay Parameters
| Parameter | Function | Typical Range | Effect on Sound |
|---|---|---|---|
| Delay Time | Time before repeat occurs | 1ms-2000ms+ | Sets timing of echo |
| Feedback | Amount of signal fed back into delay | 0-100% | Controls number of repeats |
| Mix/Wet-Dry | Balance between processed and unprocessed signal | 0-100% | Controls overall delay amount |
| Modulation | Subtle pitch/time variation | 0-100% | Adds movement and prevents static repeats |
| Tap Tempo | Sets delay time by tapping a button | N/A | Synchronizes delay with song tempo |
| Ping-Pong | Alternates repeats between left and right channels | On/Off | Creates stereo width |
| Filtering | EQ applied to the delayed signal | Varies | Makes repeats sit differently in the mix |
Types of Delay
Slapback Delay
- Characteristics: Single repeat with short delay time
- Delay Time: 60-180ms
- Feedback: Minimal (1-2 repeats)
- Best For: Vocals, guitars, creating vintage feeling
- Sound Quality: Adds thickness without obvious echoes
- Practical Tip: Great for subtle thickening when reverb feels too washy
Tempo-Synced Delay
- Characteristics: Repeats timed to match song tempo
- Delay Time: Based on note values (quarter notes, eighth notes, etc.)
- Feedback: Variable depending on desired effect
- Best For: Creating rhythmic effects that enhance the groove
- Sound Quality: Musicality that works with the song’s rhythm
- Practical Tip: Try dotted eighth notes for a classic U2-style guitar effect
Ping-Pong Delay
- Characteristics: Repeats alternate between left and right channels
- Delay Time: Often tempo-synced
- Feedback: Medium to high for multiple bounces
- Best For: Creating stereo width and movement
- Sound Quality: Dynamic, expansive stereo effect
- Practical Tip: Great for clearing the center while adding interest to the sides
Tape/Analog Delay
- Characteristics: Warm, degrading repeats with character
- Delay Time: Any setting
- Feedback: Variable
- Best For: Adding vintage character and warmth
- Sound Quality: Dark, evolving repeats with saturation
- Practical Tip: Subtle saturation and filtering give a more natural, less digital sound
Modulated Delay
- Characteristics: Repeats with subtle pitch/time variations
- Delay Time: Any setting
- Feedback: Often medium to high to showcase modulation
- Best For: Creating ethereal, evolving textures
- Sound Quality: Atmospheric, dreamy, dimensional
- Practical Tip: Subtle modulation prevents delays from sounding too perfect or mechanical
Practical Delay Mixing Tips
- Filtering: High-pass and low-pass filters on delay returns help them sit better in the mix
- Delay times: Shorter delays (<150ms) add thickness, longer delays create distinct echoes
- Musical timing: Calculate delay times based on song BPM for musical integration
- Automation: Automate delay sends for specific words or phrases rather than entire tracks
- Sidechain: Sidechain delays to duck when the source plays for cleaner results
- Stacking delays: Use multiple delays with different times for complex rhythmic effects
- Less is more: Sometimes one delay throw on a single word is more effective than constant delays
Chorus: Creating Width and Richness
What Is Chorus?
Chorus is a modulation effect that simulates the sound of multiple similar instruments or voices playing in unison by creating slightly detuned copies of the original signal. It creates a rich, shimmering sound that adds width and dimension.
Key Chorus Parameters
| Parameter | Function | Typical Range | Effect on Sound |
|---|---|---|---|
| Rate/Speed | Speed of modulation | 0.1-10 Hz | Controls how quickly the effect cycles |
| Depth | Intensity of pitch variation | 0-100% | Determines how detuned the copies become |
| Mix/Wet-Dry | Balance between processed and unprocessed signal | 0-100% | Controls overall chorus amount |
| Voices | Number of detuned copies | 1-12+ | More voices create richer, fuller effect |
| Stereo Width | Spread of voices across stereo field | 0-100% | Controls how wide the effect sounds |
| Pre-delay | Delay before chorus voices begin | 0-50ms | Creates separation from original signal |
| Waveform | Shape of modulation pattern | Sine, triangle, etc. | Changes character of the movement |
Chorus Variations
Standard Chorus
- Characteristics: Classical chorus effect with moderate settings
- Rate: 0.2-0.5 Hz
- Depth: 20-40%
- Best For: Electric and acoustic guitars, synthesizers
- Sound Quality: Lush, shimmering, slightly detuned
- Practical Tip: Subtle settings often work best in a mix
Ensemble/Multi-Voice Chorus
- Characteristics: Multiple chorus voices for thicker effect
- Rate: Various, often staggered between voices
- Depth: 30-60%
- Best For: Pads, strings, background vocals
- Sound Quality: Rich, complex, orchestral
- Practical Tip: Great for turning a single source into a group
Dimensional Chorus
- Characteristics: Minimal pitch modulation, focus on stereo enhancement
- Rate: Very slow or minimal
- Depth: Low to moderate
- Best For: Subtle stereo enhancement without obvious effects
- Sound Quality: Wide, subtle, transparent
- Practical Tip: Perfect for adding width without the “chorus sound”
Vibrato-Style Chorus
- Characteristics: Higher depth, 100% wet signal
- Rate: 4-7 Hz
- Depth: 40-70%
- Best For: Special effects, vintage sounds
- Sound Quality: Wobbly, pronounced modulation
- Practical Tip: Creates distinctive character but can be overbearing in large amounts
Practical Chorus Mixing Tips
- Stereo application: Chorus can dramatically enhance stereo width
- Subtlety: Often most effective when barely noticeable
- Pre-effect: Apply chorus before distortion/overdrive for complex harmonics
- Post-effect: Apply chorus after compression for consistent effect level
- Selective frequency: Use multiband chorus to affect only certain frequencies
- Double tracking alternative: Simulate double-tracked guitars or vocals
- Mix positioning: Use to push elements back in the mix without reverb
Combined Effects Strategies
Reverb + Delay Combinations
Pre-Delay Substitute
- Use a single delay before reverb instead of pre-delay
- Creates definition while maintaining space
- Try 80-120ms delay time with minimal feedback
Reverb into Delay
- Send reverb output into a separate delay
- Creates complex ambient textures
- Great for soundtrack and ambient music
Rhythmic Space
- Tempo-synced delay with moderate reverb
- Maintains rhythmic feel with spatial dimension
- Filter both effects differently for separation
Chorus + Reverb Combinations
Dimensional Space
- Subtle chorus into short reverb
- Creates width and depth simultaneously
- Excellent for backing vocals and pads
Modern Vocal Treatment
- Delay → Chorus → Reverb chain
- Creates complex, professional vocal sound
- Keep each effect subtle for natural result
Guitar Enhancement
- Chorus → Delay → Reverb
- Classic guitar processing chain
- Creates spacious, professional guitar sound
Creative Effect Applications
Creative Reverb Techniques
- Reverse Reverb: Reverb that swells into the original sound
- Shimmer Reverb: Pitch-shifted reverb for ethereal sounds
- Reverb Throws: Automated reverb on specific words or hits
- Ducking Reverb: Reverb that reduces when the source plays
- Gated Reverb: Reverb cut off abruptly for dramatic effect
Creative Delay Techniques
- Delay Spirals: Increasing feedback for build-ups
- Filtered Delays: High-pass or low-pass filter gets stronger with each repeat
- Pitch-Shifting Delays: Each repeat shifts in pitch
- Reverse Delays: Reversed audio for each repeat
- Granular Delays: Chopping repeats into tiny fragments
Creative Chorus Techniques
- Extreme Settings: Very slow rate, high depth for special effects
- Automation: Sweeping chorus parameters for movement
- Micro-Chorus: Extremely subtle settings for thickening without obvious effect
- Bandpassed Chorus: Apply chorus only to specific frequency ranges
- Rhythmic Tremolo-Chorus: Using LFO shapes that create rhythmic patterns
Troubleshooting Common Effects Issues
Reverb Problems
- Muddy Mix: High-pass filter the reverb around 250-300Hz
- Lack of Definition: Increase pre-delay to 40-80ms
- Harsh Reverb: Low-pass filter around 8-10kHz or use darker reverb type
- Reverb Masking Elements: Use sidechain compression so reverb ducks when important elements play
- Unnatural Sound: Combine multiple reverb types for more complex spaces
Delay Problems
- Delay Cluttering Mix: Synchronize to tempo and high-pass filter
- Obvious, Distracting Repeats: Lower mix level and add subtle modulation
- Delays Fighting with Rhythm: Adjust timing to complement rather than fight the groove
- Stereo Delay Issues in Mono: Check mono compatibility or reduce stereo width
- Messy Buildups: Use automation to control feedback in different sections
Chorus Problems
- Seasick Feeling: Reduce depth and/or rate
- Phase Cancellation: Check mono compatibility, reduce stereo width
- Obvious “80s Chorus” Sound: Use more voices with less individual depth
- Lost Transients: Apply chorus to a parallel track and blend
- Pitch Inconsistency: Use pre-delay to maintain attack clarity
Resources for Further Learning
Books
- “Mixing with Effects” by Eric Tarr
- “Creative Effects Processing” by Dave Bessell
- “Mixing Secrets for the Small Studio” by Mike Senior
Online Courses
- “Time-Based Processing Masterclass” (various platforms)
- “Advanced Reverb Techniques” (various platforms)
- “Delay as a Creative Tool” (various platforms)
Software and Plugins
- Versatile Reverbs: Valhalla VintageVerb, FabFilter Pro-R, Lexicon PCM Native
- Creative Delays: SoundToys EchoBoy, Valhalla Delay, Native Instruments Replika XT
- Unique Chorus: SoundToys Crystallizer, Eventide UltraTap, TAL-Chorus-LX
Remember that these effects are tools to enhance your mix. The goal is to use them intentionally to serve the song, not to apply them just because you can. Start with subtle settings and increase as needed, always considering the context of the full mix.