Table of Contents
Table of Contents
Table of Contents
Table of Contents
Table of Contents
Introduction
Mixing is the art of balancing and shaping individual tracks so they work together as a cohesive song. Three tools form the foundation of every mix: equalization (EQ), compression, and reverb. EQ carves space for each instrument by adjusting frequency content; compression controls dynamic range so quiet parts are audible and loud parts do not distort; reverb places instruments in a shared acoustic space. Master these three processors and you can achieve a professional mix with any DAW and a decent pair of headphones.
Table of Contents
- EQ Fundamentals: Frequency Carving
- Compression: Dynamics and Punch
- Reverb: Space and Depth
- Signal Chain Order
- Practice Exercises
- Frequently Asked Questions
Key Takeaways
- Subtractive EQ (cutting frequencies) is safer than additive EQ (boosting). Cut before you boost.
- Compression ratio 2:1 to 4:1 is standard for most tracks. Higher ratios create more aggressive dynamic control.
- Attack time controls transient preservation. Fast attack (1-10ms) tames peaks, slow attack (30-50ms) lets punch through.
- Reverb send (aux bus) is better than insert reverb for mixing. One shared reverb creates coherent space.
- High-pass filter every non-bass track at 80-120Hz to remove mud and make room for kick and bass.
EQ Fundamentals: Frequency Carving
Equalization adjusts the balance of frequencies in a sound. A parametric EQ typically offers four to eight bands, each with adjustable frequency, gain, and Q (bandwidth). The four common filter types are high-pass (cuts below a frequency), low-pass (cuts above), bell (boosts or cuts a range), and shelf (adjusts everything above or below a point). Start every mix by high-pass filtering every track that does not need low end: vocals at 80-100Hz, guitars at 80-120Hz, pianos at 60-80Hz, hi-hats at 200-300Hz. This removes low-frequency rumble and clears space for the kick drum and bass. The kick and bass themselves can share the 40-250Hz region through sidechain compression or careful EQ complement: let the kick dominate 60-100Hz and the bass occupy 100-250Hz.
Finding Problem Frequencies
When a track sounds muddy or harsh, sweep a narrow boost (high Q, +6dB) across the frequency spectrum to locate the offending frequency. Once you find it, cut 3-6dB at that frequency with a narrow Q. For vocals, cut around 200-400Hz to reduce boxiness, and cut around 3-5kHz to tame sibilance if needed. Boost vocal presence at 2-4kHz with a wide Q for clarity. For guitars, cut around 300-500Hz to reduce congestion, and boost around 1-3kHz for bite. For kick drums, boost around 60-100Hz for thump and cut around 300-500Hz to reduce hollowness. Snare benefits from a boost around 150-250Hz for body and 3-5kHz for crack. A common mistake is boosting too much. Gain reduction through EQ should primarily be subtractive. Boost only when a track clearly lacks something, and keep boosts under 3dB. A mix built on cuts rather than boosts stays cleaner and translates better across playback systems.
Compression: Dynamics and Punch
Compression reduces the dynamic range of a signal by attenuating peaks above a set threshold. The four main controls are threshold (the level at which compression begins), ratio (how much compression is applied above the threshold), attack (how quickly the compressor responds after the threshold is crossed), and release (how quickly the compressor stops compressing after the signal falls below threshold). A 2:1 ratio means that for every 2dB above threshold, only 1dB passes through. Vocals typically use 3:1 to 4:1 ratio with moderate attack (10-20ms) and release (40-80ms). Drums benefit from faster attack (1-5ms) to catch transients and shape the hit. Bass works well with medium attack (20-30ms) to let the initial pluck through before compressing the sustain.
Compressor Types
Different compressor circuits produce different tonal characteristics. VCA compressors (like the SSL G-Bus) are clean and precise, ideal for drum bus and parallel compression. FET compressors (like the UA 1176) are fast and aggressive, excellent for punchy vocals and snare drums. Optical compressors (like the LA-2A) are smooth and gradual, perfect for bass and vocal leveling. Vari-mu compressors (like the Fairchild 670) add warmth and glue, often used on the master bus. In-the-box plugin emulations capture these characteristics accurately. Most DAWs include at least one of each type. Learn one compressor type thoroughly before moving to the next. Start with a VCA compressor on drums and an optical compressor on vocals, and you can handle the majority of mixing scenarios.
Parallel Compression
Parallel compression (also called New York compression) blends a heavily compressed version of a track with the dry signal. Set up an auxiliary send with a compressor at 8:1 to 20:1 ratio, fast attack, and heavy gain reduction (10-20dB). Blend the compressed signal underneath the dry signal until you hear the track gain density and presence without losing its natural dynamics. Parallel compression works particularly well on drums, giving them power and sustain while preserving transient impact. Many mix engineers use parallel compression on the entire drum bus as a standard part of their mixing template.
Reverb: Space and Depth
Reverb simulates the reflections of sound in a physical space. The key parameters are decay time (how long the reverb lasts, measured in seconds), pre-delay (the gap between the dry sound and the first reflections), room size (the perceived size of the virtual space), diffusion (how dense the reflections are), and wet/dry mix (the balance between the processed and unprocessed signal). Use reverb sends rather than inserts: create one or two reverb auxiliary tracks (a room reverb with 1.0-1.5s decay and a hall/plate with 2.0-3.0s decay) and send multiple tracks to them. This keeps all instruments sounding like they belong in the same space. Vocals typically receive the most reverb (15-30% wet), while low-end instruments like kick and bass receive little or none (0-5%) to maintain clarity and punch.
Reverb Types
Room reverb simulates a small to medium room with short decay (0.5-1.5s). It adds natural ambience without sounding obviously effected. Hall reverb simulates a concert hall with longer decay (1.5-4.0s) and creates a lush, expansive sound. Plate reverb uses a large metal plate to create a dense, smooth reverb with moderate decay (1.5-3.0s) and works beautifully on vocals and snare. Spring reverb is a guitar-amp style reverb with a bouncy character, common on surf and rock guitar. Convolution reverb uses impulse responses (IRs) captured from real spaces and hardware to create realistic acoustic simulations. For most mixes, a room reverb on drums and a plate or hall reverb on vocals and lead instruments provide all the spatial depth you need.
Signal Chain Order
The order of processors on a channel strip matters. A standard signal chain runs: gain staging (input level adjustment) first, then EQ, then compression, then saturation or distortion, then modulation effects (chorus, flanger), then reverb or delay sends. The reason for EQ-before-compression is that EQ removes problematic frequencies that could cause the compressor to react to frequencies you do not want compressed. Some engineers prefer compression before EQ for a different reason: compressing first evens out the level so the EQ responds more consistently. Both approaches are valid; try both and listen for the difference. For the master bus, the chain typically runs: EQ for corrective adjustments, compression for glue (1.5:1 to 2:1 ratio, 1-3dB reduction), then a limiter to catch stray peaks.
Practice Exercises
| Exercise | Task | Goal |
|---|---|---|
| 1 | High-pass every non-bass track in a mix | Remove mud and clean up low end |
| 2 | Use subtractive EQ to fix one muddy track | Practice frequency sweeping and cutting |
| 3 | Compress a vocal track with 3:1 ratio, 15ms attack, 60ms release | Learn standard vocal compression |
| 4 | Set up a parallel compression bus for drums | Apply parallel compression technique |
| 5 | Create two reverb sends (room and plate), route 3 tracks to each | Build shared reverb space for cohesion |
Frequently Asked Questions
- Should I EQ before or after compression?
- EQ before compression prevents the compressor from reacting to problematic frequencies. EQ after compression can shape the tone more aggressively since the level is already even. There is no single correct answer; try both approaches on each track and use what sounds better.
- What reverb settings work best for vocals?
- For lead vocals, use a plate or hall reverb with 1.5-2.5s decay, 20-40ms pre-delay, and 15-25% wet mix. The pre-delay keeps the vocal clear while the reverb adds depth. Cut the reverb's low end with a high-pass filter at 300-500Hz to prevent muddiness.
- How much gain reduction is normal on a compressor?
- For individual tracks, 3-6dB of gain reduction is standard. For drum bus, 2-4dB. For master bus, 1-3dB. More than 6dB on individual tracks often indicates the source needs re-recording or gain staging adjustments.
- What is the difference between a compressor and a limiter?
- A limiter is essentially a compressor with a very high ratio (10:1 or higher) and fast attack. Its purpose is to catch peaks and prevent clipping, while a compressor shapes the overall dynamic envelope. Limiters are typically used on the master bus and individual tracks that need hard peak control.
- Why does my mix sound amateur compared to commercial tracks?
- Three common reasons: (1) too much low-end buildup from not high-passing tracks, (2) overusing reverb which creates a washy indistinct sound, and (3) not using reference tracks to compare your mix level-for-level with professional productions. Use a reference track matching the genre of your mix and A/B compare frequently.
Conclusion
EQ, compression, and reverb are the three pillars of mixing. Start with subtractive EQ to carve space, apply compression to control dynamics and add punch, and use shared reverb sends to place everything in a coherent space. Practice these fundamentals on one track at a time before layering more advanced techniques. Every professional mix is built on this foundation.