Mastering Chain Order Signal Chain From EQ to Limiter

A mastering chain is a series of audio processors applied to your stereo mix (or stems) in a specific order before the final bounce. Each processor shapes the signal in a particular way, and the order you place them in determines how they interact. Running a compressor before an EQ produces a fundamentally different result than running the EQ first. This guide, part of our mastering and delivery hub, walks through the standard mastering signal chain stage by stage so you understand not just what to use, but why each piece sits where it does.

The chain below is a proven starting point. It is not the only valid order, and experienced engineers break the rules deliberately when the material calls for it. But if you are building your first mastering chain or want a reliable template to iterate from, this sequence will serve you well on the vast majority of mixes.

Stage 1: Corrective EQ (Linear Phase)

The first processor in your chain handles surgical cleanup. A linear phase EQ is ideal here because it does not introduce phase shift, which matters when you are making precise cuts on a full stereo mix. The goal is subtractive: remove problems, not add character.

Common corrective moves include a high-pass filter at 20 to 30 Hz to remove sub-bass rumble that eats headroom without adding musicality. If the mix has a muddy buildup in the 200 to 400 Hz range, a gentle cut of 1 to 2 dB with a wide Q can open things up. Harsh resonances in the 2 to 5 kHz range might need a narrow notch of 1 to 3 dB.

Keep your moves small. If you find yourself cutting or boosting more than 3 dB at this stage, the problem likely belongs in the mix, not the master. Send the mix back for revision rather than trying to fix it with mastering EQ.

Stage 2: Gentle Compression

After cleaning up the frequency spectrum, compression controls the dynamic range. Mastering compression is fundamentally different from mix-bus compression. You are working with a finished stereo signal where every element is already balanced, so the compressor needs to be transparent.

Use a ratio between 1.5:1 and 2:1. Set a slow attack time (20 to 50 ms) so transients pass through unaffected, and a medium release (100 to 300 ms, or use auto-release if your compressor offers it). You are looking for 1 to 3 dB of gain reduction on the loudest peaks. If the needle is moving more than 3 dB consistently, you are compressing too hard.

The purpose is to glue the mix together slightly and reduce the gap between the loudest and quietest moments. This makes the limiter's job easier later in the chain and results in a more consistent perceived loudness without the pumping artifacts that come from asking a limiter to do all the dynamic control. Understanding your LUFS targets will help you decide how much compression to apply.

Stage 3: Tonal EQ (Broad Strokes)

The second EQ in the chain is additive and musical. Where the corrective EQ removed problems, the tonal EQ shapes character. A minimum phase EQ works well here because the slight phase shift it introduces adds a musical quality that many engineers prefer for broad tonal shaping.

Typical moves include a gentle high shelf boost of 0.5 to 2 dB starting around 8 to 12 kHz to add air and presence. A low shelf boost of 0.5 to 1.5 dB below 80 Hz adds warmth and weight. A subtle bump in the 2 to 4 kHz range can bring vocals forward in the mix.

This stage is placed after compression because the compressor can change the tonal balance of the signal. Compressing a signal that has a lot of low-end energy will result in the compressor reacting primarily to the bass, which can make the track sound duller. By compressing first and then EQing for tone, you are shaping the signal after dynamics are controlled, which gives you more predictable results.

Stage 4: Stereo Imaging and Mid-Side Processing

Stereo imaging processors adjust the width of the stereo field. Mid-side (M/S) processing is particularly useful at this stage because it lets you treat the center of the mix independently from the sides. You can widen the high frequencies on the sides while keeping the bass and vocals locked to the center.

A common technique is to apply a high-pass filter to the side channel at 150 to 200 Hz. This removes low-frequency content from the sides, which tightens the bass and improves mono compatibility. You can also gently boost the side channel above 5 kHz by 1 to 2 dB to create a sense of extra width in the high end without affecting the center-panned vocals or bass.

Be conservative with stereo widening. A track that sounds impressively wide on headphones may develop phase cancellation issues on mono playback systems like phone speakers and Bluetooth speakers. Always check your master in mono after adjusting stereo imaging.

Stage 5: Saturation and Harmonic Enhancement

Saturation adds harmonic content that makes the signal sound richer and warmer. In a mastering context, this is used very subtly. Tape saturation emulations, tube-style harmonic generators, or transformer colorations all work. The goal is a gentle harmonic richness that you feel more than hear.

Place saturation before the limiter because the harmonics it generates add energy to the signal. If you saturated after limiting, those new harmonics could push the signal past your true peak ceiling. Keep the drive low, somewhere around 5 to 15 percent of your plugin's range. If you can clearly hear the saturation as a distinct effect, you have gone too far for mastering purposes.

Not every master needs saturation. If your mix already has rich harmonic content from analog-modeled plugins or actual hardware in the signal chain, adding more saturation at the mastering stage may make the track sound muddy or harsh. Trust your ears and A/B frequently with the saturator bypassed.

Stage 6: Brick-Wall Limiter

The limiter is always the last processor in the chain. Its job is twofold: bring the overall loudness up to your target integrated LUFS and ensure the true peak never exceeds your ceiling (typically -1 dBTP). A brick-wall limiter catches every peak that would exceed the ceiling and pulls it down with an infinite ratio and zero attack time.

Set the output ceiling to -1 dBTP with true peak mode enabled. Then push the input gain until your integrated LUFS meter reads close to your target. For most streaming distribution, that target is -14 LUFS. Watch for gain reduction exceeding 4 to 6 dB. If your limiter is working harder than that, the master will start to sound crushed and distorted.

Different limiters have different characters. Some are transparent and surgical (like FabFilter Pro-L2), others add color (like the Waves L2). For mastering, transparency usually wins. You want the limiter to control peaks without altering the tonal balance or stereo image you carefully built in the preceding stages. When you are ready to evaluate your results, understanding the differences between AI and human mastering can help you decide whether your chain is achieving professional results.

Gain Staging Between Processors

Every processor in your chain changes the level of the signal. An EQ boost adds energy. A compressor reduces peaks but may add makeup gain. Saturation adds harmonic content. If you do not manage these level changes, each subsequent processor receives a signal at a different level than you intended, and the cumulative effect can be unpredictable.

The rule is simple: match the output level of each processor to its input level. If your corrective EQ cuts 1.5 dB of mud, add 1.5 dB of makeup gain so the compressor after it sees the same level. This lets you evaluate each stage purely by its tonal or dynamic effect, not by a loudness difference that tricks your ears into thinking louder is better.

Many plugins have input and output level meters built in. Use them. If yours do not, insert a gain utility plugin between each stage and trim the levels. It takes an extra minute and saves you from chasing problems caused by inconsistent levels.

When to Leave Things Alone

The best mastering engineers know when not to process. If a mix arrives well-balanced with good dynamics and appropriate headroom, the mastering chain might be nothing more than a gentle EQ curve and a limiter. Adding compression, saturation, and stereo widening because they are in your template, not because the mix needs them, is the fastest way to make a good mix worse. Bypass each processor one at a time and ask yourself honestly whether it is improving the signal. If you are not sure, leave it off.