Relab Development Maselec MLA-4

The Maselec MLA-4 Triband Compressor/Expander is the first and only officially endorsed software recreation of the legendary hardware unit, developed in direct collaboration with Leif Mases.

Designed for mixing, mastering, and stem processing, the MLA-4 delivers natural, musical dynamic shaping with precise multiband control—now enhanced with modern workflow features only possible in software.

Whether refining a final master, shaping a mix bus, or restoring dynamics in a crushed stem, the MLA-4 delivers the depth and musicality of a revered analog mastering tool—meticulously recreated in plug-in form.

Dynamic Control That Works With Your Mix - Not Against It

For mixing and mastering engineers who need precise dynamic control without compromising mix integrity, most multiband compressors create more issues than they solve, often introducing phase distortion, transient smearing, and tonal imbalance.

High-end analog mastering tools set the standard for depth and cohesion, while most digital multiband solutions fail to capture the nuance and responsiveness professionals demand.

With the Maselec MLA-4 you get the best of both worlds, so you can:

With surgical yet expressive control, the Maselec MLA-4 ensures that every adjustment serves the music first – without second-guessing settings, battling artifacts, or fighting against the processor itself.

The Power of Compression and Expansion Together

Although multiband processing is nothing new—the ability to compress and expand each band both independently and interactively unlocks creative control rarely found in a single processor.

With compression (up to 6:1) and expansion (down to 1:2) per band, you can tighten low-end boom while lifting air in the highs, or recover lost transients from an over-processed mix—all in real-time.

Need to control bass while enhancing top-end detail? Done. Want to restore natural dynamics without disrupting tonal balance?

The MLA-4 makes it effortless.

Sculpt Dynamics with Surgical Precision

The MLA-4 simplifies dynamic shaping with precise per-band threshold, ratio, attack, and release controls, allowing compression and expansion to work in harmony.

Dial in tight low-end, articulate mids, and smooth highs without unwanted pumping, dulling, or overcorrection. Unlike conventional designs, every adjustment feels natural, preserving the integrity of your mix.

From mix bus refinement to final mastering, the MLA-4 delivers pure, effortless dynamic control—so you can focus on the music.

Smarter Sidechain Linking for Smoother Dynamics

Most multiband sidechain behavior is an afterthought—either all bands react together or don’t. The MLA-4 redefines that approach with a five-mode sidechain linking system that adapts compression and expansion behavior to the material.

Need full-band cohesion? Engage full linking. Want surgical control? Keep bands independent. But the real magic happens in the in-between modes—where low frequencies can shape mid and high-band compression and expansion maintaining clarity without overcorrecting dynamics.

The difference is immediate: more control, fewer compromises, and a dynamic response that feels like the mix is breathing—not just reacting.

Preserve Your Sound, Perfect Your Dynamics

Heavy compression or expansion in one band can throw off the balance of your mix, forcing you to compensate manually.

The MLA-4’s Auto Spectral Balance eliminates this problem by intelligently applying independent gain compensation to the low, mid, and high bands.

And with Auto Level also at your disposal, you can choose whether to preserve the mix’s tonal balance or reshape it to fit your creative vision.

The result? Compression that works invisibly—sculpting dynamics without unintentional tonal shifts.

Add Harmonics Only Where You Want Them

Multiband processing just got more flexible: Per-band THD control lets you decide exactly where harmonic color is introduced—or where it’s left untouched.

Instead of applying distortion across the entire spectrum, the MLA-4 allows you to selectively add warmth to the lows, richness to the mids, or keep the highs pristine. No unnecessary saturation, no compromises.

With this level of control, harmonic enhancement becomes a choice, not a side effect, ensuring that every frequency range behaves exactly as you intend.

Hear the Problem, Fix the Problem

Precision starts with the ability to hear exactly what’s happening in the mix. The MLA-4 software expands on the original hardware with per-band solo and left/right cut giving you deeper insight and control over your dynamics processing.

Left and right cut functions let you focus on a single channel’s contribution to the processing—essential for fine-tuning stereo balance. Per-band soloing allows you to isolate lows, mids, or highs to hear exactly how compression or expansion is affecting each frequency range.

By isolating what matters most, you gain the clarity to make precise, intentional dynamic choices—without second-guessing.

The Power of a $10,000 Studio Classic at an Accessible Price

For decades, high-end mastering studios have relied on the original Maselec MLA-4 hardware to shape dynamics with absolute precision. But at nearly $10,000, it’s been an exclusive tool, reserved for elite studios and top-tier engineers.

Now, for the first time, that same uncompromising control, musicality, and phase-coherent processing is available in software—at a fraction of the cost.

Here’s the real value of the MLA-4 plug-in:

Your mixes deserve the best—without the price tag that comes with it. With the MLA-4, you’re getting the power of a mastering staple for less than 2% of the hardware cost—and with features only possible in software.

Once you hear what it can do for your mixes, you’ll wonder how you ever worked without it.

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