Today, I want to clear up a common question I used to ask myself all the time: Can you combine soundproofing with bass traps?

I used to see pictures of studios where people seemed to be doing just that. They’d have some kind of open wall construction with the insulation material visible, maybe even covered with fabric. And I thought, “Is that some secret hack? Are they building walls that double as bass traps?”

Is it better to combine the two? Or is something else going on here?

I know a lot of you have wondered about this too, so let’s walk through it step by step. By the end of this post, you’ll understand exactly why combining soundproofing and bass traps doesn’t work, and what you should be doing instead.

What Are You Really Trying to Do with Soundproofing?

First off, let’s start with what soundproofing is actually supposed to do.

When you’re building an isolating wall structure, your goal is to prevent sound transmission. Basically, you’re trying to reflect as much sound back into the room as possible, especially at low frequencies. To do this, you need something heavy. Think concrete, or multiple layers of drywall.

The insulation material that we use in acoustic treatment does play a role in the soundproofing process, but here’s the thing: It’s not the main thing absorbing the sound you don’t want to escape. What you’re actually doing is building a structure that reflects sound energy back into the room.

That’s what gives you isolation. Not absorption.

A Good Soundproofing Setup – What It Looks Like

Let’s take a look at a typical soundproofing structure. I grabbed this example from the Master Handbook of Acoustics by Everest and Pohlmann.

Credit: Alton Everest, F. and Pohlmann, K.C., 2009. Master Handbook of Acoustics. Mc Graw Hill.

Imagine a cross-section of an isolating wall. In the best-performing setup, you have two separate studwork frames, each filled with insulation material. Between them is an air gap of about 4 to 10 inches. Then, on both sides of the frames, you’ve got double layers of drywall.

So what gives this structure its soundproofing capability? It’s the mass-air-mass combination. The heavy mass of the drywall, separated by an air gap, is what reflects sound back into the room.

If you build your entire room like this—walls, floor, ceiling, and all sealed up—you’ll end up with an isolated, airtight structure. That’s how you create an isolated room. But here’s the kicker: Inside this perfectly isolated room, it’ll sound awful. Like, concrete bunker awful.

That’s because soundproofing and acoustic treatment are two separate tasks. You need both—but they do completely different things.

Why You Can’t Combine Soundproofing and Acoustic Treatment

Let’s say you try to combine soundproofing with bass traps.

In our example above, you’d basically remove half of the soundproofing structure. You’d take away one set of studwork and the air gap. What you’re left with is just drywall on one side and insulation on the other.

Credit: Alton Everest, F. and Pohlmann, K.C., 2009. Master Handbook of Acoustics. Mc Graw Hill.

Now, what happens when you do this?

1. Soundproofing takes a hit. You’re removing the heavy mass and the air gap that are crucial for reflecting sound. Without them, your structure becomes much less effective at keeping sound from escaping the room.
2. Bass trapping suffers too. When you only have a couple of inches of insulation material behind the drywall, it won’t give you any decent absorption at low frequencies. You’ll only be treating the mid and high frequencies, leaving your low end untreated—and that’s where most people struggle anyway.

So, if you try to combine soundproofing and bass traps into a single structure, you end up with something that doesn’t do either job well. You’ll get a dead-sounding room with no low-end absorption and poor soundproofing.

Treat Soundproofing and Acoustic Treatment as Separate Tasks

This is why we separate soundproofing and acoustic treatment into two different planning stages. They require completely different approaches and materials.

In fact, many professionals specialize in just one or the other because the skill sets and materials are so different. It’s important to hire the right expert for each job, whether you’re focusing on isolation or acoustic treatment.

The problem is, I see too many people building a soundproofed room and forgetting to treat it acoustically. They end up with an isolated room that sounds terrible inside because they skipped the acoustic treatment. Don't be that person.

If you're planning to build a studio, make sure you budget for both soundproofing and acoustic treatment. Yes, it might mean more planning and more expense, but if you want a room that sounds great and keeps the noise in, you need to handle each aspect properly.

Wrapping Up: Don’t Combine These Two

So, to answer the original question: No, you shouldn’t combine soundproofing and bass traps.

They require different strategies, and combining them will only compromise both. Keep them separate and give each the attention it deserves. Your studio will thank you for it.

Key Takeaways:

• Soundproofing (isolation) and bass trapping (acoustic treatment) are two completely separate tasks.
• Soundproofing reflects sound energy back into the room using heavy mass and air gaps.
• Bass trapping requires porous materials to absorb low-end frequencies, and this can’t be done with just soundproofing materials.
• Combining the two compromises both, leading to poor results in both isolation and acoustic treatment.

Make sure you handle each task separately in your studio for the best results.