FabFilter Pro-Q4 vs Soothe 2: Which Audio Plugin Wins?

When FabFilter finally announced Pro-Q 4 after six years, I was immediately curious. I’ve been using FabFilter EQs for years, and when FabFilter Pro-Q4 introduced Spectral Dynamics after a six-year gap since Pro-Q3, the conversation in professional audio circles has shifted.

Could Pro-Q4’s new feature make Soothe2 unnecessary?

As someone who’s used Oeksound Soothe 2 religiously since it came out, and upgraded to Pro-Q 4 the moment it was released, I’ve put them head-to-head in real projects to see exactly where each shines, and where one still outperforms the other.

Spoiler: these two plugins are not trying to do the exact same job, but there’s definitely overlap worth talking about.

The first thing to understand is that Pro-Q 4 is not just about Spectral Dynamics. It’s still one of the most flexible, clean, and precise EQs you can have in a mix. Spectral Dynamics is just one feature inside a full-featured EQ powerhouse.

Soothe 2, on the other hand, is a more specialized tool. If Pro-Q 4 is like a general-purpose audio magazine that covers everything from EQ to M/S processing, then Soothe 2 is like a niche magazine dedicated entirely to the art of resonance control.

So when comparing the two, I focus only on Pro-Q 4’s Spectral Dynamics mode versus Soothe 2.

Pro-Q 4 as a Dynamic & Spectral EQ

Pro-Q4 is, first and foremost, a full-spectrum parametric EQ with up to 24 bands, Natural Phase and Linear Phase processing, M/S control, and precision filters.

In Pro-Q 4, every EQ band can be made dynamic with the Make Dynamic function. Flip that to Make Spectral, and instead of adjusting the gain of an entire frequency band, it detects and reduces only the most prominent resonances within that band.

This is where Spectral Density comes into play. Lower values act more like a traditional dynamic EQ, applying broader gain reductions. Increase it, and it behaves more like Soothe 2’s Sharpness parameter, zeroing in on specific resonances with surgical precision.

Like any dynamic EQ, you still get control over threshold, ratio (Dynamic Range), attack, and release, so you can shape exactly how it reacts. To me, Spectral Dynamics feels like an advanced extension of what dynamic EQ has always been.

Soothe 2 – The Intelligent Resonance Tamer

Soothe 2 is not strictly a dynamic EQ, although it can behave similarly in certain situations. Instead, it continuously analyzes the entire input signal in real time, identifying resonances across the spectrum and reducing them dynamically, even within complex, dense mixes.

Unlike a traditional dynamic EQ that responds only when a specific threshold is exceeded in one band, the Soothe2 plugin works proactively, scanning the full signal and automatically cutting resonances as they occur.

You can still guide it, boost or cut reduction in certain ranges, use filters to exclude parts of the spectrum, but it’s doing more under the hood than a standard dynamic EQ. Its Sharpness and Selectivity parameters make it extremely precise at hunting down problem resonances.

Where Pro-Q 4 shines in narrow, targeted resonance removal, Soothe 2 is unmatched at broad-spectrum resonance control without making the mix feel “EQ’d to death.”

Real-World Use Cases

In practice, I reach for Pro-Q 4 when I know exactly where the problem is and I want maximum control over how it’s reduced. It’s fast, visual, and precise.

Soothe 2 comes out when I want that extra layer of “set and forget” magic, particularly on mix buses or harsh vocals. Here, Soothe2 still had the edge. With just a few tweaks to Sharpness, Selectivity, and Depth, it smoothed the harshness without dulling the vocal.

Pro-Q4 could handle it, but required more manual frequency targeting and didn’t maintain the same effortless transparency.

One of my favorite ways to use Soothe 2 is in its external sidechain mode, where it targets resonances created by overlapping frequency ranges between two tracks. Pro-Q 4 can also do external sidechain processing, but in a slightly more manual way.

Soothe 2, in my experience, is still my go-to for taming high-end harshness or sibilance in a way that feels almost invisible. It can be subtle yet transformative when set correctly. Pro-Q 4 can handle some of this work, but it’s not quite as effortless.

My Verdict

Pro-Q 4’s Spectral Dynamics is not a full replacement for Soothe 2, but that’s not a negative. These are two different tools with different design philosophies.

• Pro-Q 4 gives you surgical precision, flexibility, and the benefit of having it all in a single, world-class EQ plugin.
• Soothe 2 gives you intelligent, almost “AI-like” resonance control across the spectrum with minimal fuss.

For me, they complement each other beautifully. I wouldn’t want to lose either from my workflow.

Final Thought

FabFilter has taken Pro-Q 4 well beyond “just a better EQ than your DAW stock plugin.” With Spectral Dynamics, it’s now competing in territory that used to be reserved for specialty processors like Soothe 2 or Gullfoss, while still doing all the things that made it the go-to EQ for so many of us.

If you’re curious to hear Pro-Q 4 at its best, check out my FabFilter Pro-Q4 Presets Pack. It’s packed with my own mixing and mastering settings that I use every day in my projects.