Home Recording Basics Ep. 04: Bass Traps
In your average room, uneven bass response can be a real problem. Play a loud 60 Hz test tone through your monitors and walk around the room. If you don’t have specialized acoustic absorption called a bass trap set up, you’ll likely notice the volume of that test tone getting louder and softer as you move around the room.
How bass traps control low frequency sound
This volume change is caused by low frequency sound in the room interfering w itself, causing focal areas of uneven sound energy called a “room mode”. If you produce music in a room with uncontrolled room modes, you will get uneven bass balance in your finished recordings. That’s because the bass you’re hearing out of your speakers is not an accurate reflection of what your music actually sounds like, and this will cause you to make inconsistent decisions during the recording and mixing process.
Bass energy collects at boundary points between flat surfaces, especially in the corners of a room where all surfaces meet. So, bass traps can be placed in these locations to absorb low frequency sound energy, and help control room modes. This will make your room’s bass response much more tight and even, and the music being made in it much more consistent sounding across a variety of playback systems.
Bass trap design
Bass traps are often triangular-prism-shaped wood frames filled with acoustic absorption, designed to fit in the corner spaces of a room. Here’s one example from GIK Acoustics:
But, there are many ways to design a bass trap.
The big thing to keep in mind is that bass acoustic control requires lots of absorption volume to be effective, up to several feet thick of acoustic absorption ideally. We talk more about the physics of why this is important in our related article Bass Traps and Air Gaps.
Commercially, there’s all kinds of tricks you can use if you’re building a space from scratch, but for a typical DIY home studio the corner style bass traps work quite well. Fill in as many corners of your room as you can with bass traps, all of them if possible!
Why bass traps matter
Bass traps and acoustics are not always the sexiest of investments, but they have huge bang for the buck.
You will notice a massive increase in quality of work between recording/mixing in a room with proper acoustic treatment vs. an uncontrolled room. That’s because you need to hear what you’re doing as accurately as possible if you want to get to the highest quality end result. Making music in a room without bass traps is akin to trying to paint while wearing dark sunglasses-possible to do, but very difficult to come up with a high quality product consistently. If you want your music to sound its best, the bass balance needs to be correct. Flobby, uneven bass can often make your recordings sound lower in quality.
I recommend investing in this area early on in your studio development. Bass traps in your control room and/or recording space is one of the first things you should get set up in your studio!
