In part two of the series I added some carpet on the floor, and by doing that I got rid of most of the echo in the room. Now it's time to take things to the next level and refine the sound treatment.
What You Need: Sound Sculpting Materials
I'll be using two types of panels: sound dampening foam panels (I just call these "panels" from now on) and bass traps.
I
have four bass traps, each measuring one meter in height and about 30 cm
width on each side. I also have three acoustical panels, each measuring
two meters in length by one meter in height. They are about 6 cm thick.
This is enough for the light application I'm preparing for—mostly spoken
word—but if you're going to regularly record musicians, for example,
you may need more (or a different configuration) for the size and shape
of your room.
Now, why two different types of materials? It's simple. The foam panels will do a very good job in absorbing mid- to high-frequency sounds. The bass traps are best at absorbing low-frequency sounds. By adding sound-absorbing objects of multiple densities to your room, you make sure to cover as much of the frequency range as possible.
A word on foam: go for quality.
We've had some cheap foam acoustic material release noxious gases. Look for
reputable brands and read reviews before buying.
Now, how should these be mounted without damaging the walls? Let's find out.
How to Put Up the Sound Panels
The panels and bass traps are up, but what's up with the placement of the three larger ones?
Panel Placement
The panels you put up should negate the sound reflection as much as possible. That's why two of them are put directly opposite each other on the side walls (Image 3).
The third panel is placed in front of me to stop the sounds reflected by that wall. Ideally, I would want a fourth panel placed on the wall behind me, but since that's the backdrop I cannot do that.
DIY Vocal Booth Part 1: The Key to a Good Vocal/Voice Recording
How to Analyse Room Reverb for Voice Recording
All in all, I'm really happy with the results from just using these three large panels. There is still a little bit of echo, but the lavalier microphone doesn't pick up too much of it.
There's a bit of a balancing act here: you want to use enough of these panels to get your voice and the room tone sounding better, but not so many that it kills all the bass and mutes the sound. You also don't want to put up so many treatments that the room is difficult to use as a video studio. So I'll leave the fourth panel off the back wall, where the backdrop will go, for now.
I purchased these panels so my task was easier, but what if you're on a tighter budget? Well, you can make these yourself:
Make Your Own Sound Sculpting Materials
With a little bit of time and effort, you can create some of these panels yourself and at a much lower cost.
The first, and in some ways easiest, way is to repeat the last tutorial. What works on the floor works just as well on the walls: hanging carpets makes for great noise shaping. And it can look cool! Just be careful that the colour of the carpet doesn't reflect too much in your lighting (we'll cover lighting later in this series).
Here are some great resources that will help you do just that and also help you learn more about room acoustics:
Next Steps
The acoustic treatment is now finished, so it's time to move on and create the backdrop. I'll do that in the next tutorial.
