Soundproofing Vs. Sound Absorption: What's the Difference?

Soundproofing Vs. Sound Absorption

Do you want to play the drums, but your neighbors are complaining– or any instrument at that?

Soundproofing and sound absorption is often something that many people tend to get confused about. Is there even a difference?

Today we’re talking about that with ways to keep our neighbors from banging angrily on our doors.

First thing’s first. Let’s define the differences between soundproofing and sound absorption.

When it comes to soundproofing, this actually involves the way your room, house, apartment, etc… is constructed. When it comes to soundproofing a room for example, there’s actually another set of walls built within the original walls of that room.

A room inside a room, y’know, Inception kind of stuff.

The reason why it’s structured this way is so there’s an air gap between the original wall and the soundproofed wall barrier. This design helps trap those really low frequencies that can travel through the normal, original walls. In essence, you’re blocking the sound from entering or exiting the room.

Think about it. When we record low frequencies like a bass, tuba, or any other bass instrument, the waves that get recorded are very big and wide, compared to a higher frequency instrument like a flute or oboe.

You can probably test this out by recording yourself on your instrument and playing your lowest note vs. your highest note on your instrument. The lowest note will produce larger, wider waves than your highest note, which will produce smaller, tighter waveforms.

Another way you can think of is the way it feels when you’re standing outside of a club. You’ll hear more of the bass frequencies than you do the higher frequencies. This is because, again, those lower frequencies have more energy than the higher frequencies, allowing them to pass through more things.

With that extra gap of air, when it comes to a soundproofed room, it’s wide enough to make it harder for the bass frequencies to travel outside the room, compared to a room without soundproof walls.

While having a soundproofed room is the ideal for recording situations, it isn’t always ideal when it comes to time and our budgets.

So what is that at-home musician to do??

Most people are likely going to want to go with sound absorption, or sound dampening techniques. This is different from soundproofing because we aren’t building a room inside another room. With this, what we’re doing is gathering soft materials that will help reduce the amount of reverb reflections in your room.

Sound absorption won’t entirely fix frequencies from escaping your room or home, but it can make it a lot more tolerable for your neighbors to handle, and it’s better than nothing at all.

Sound absorption comes in a variety of ways such as acoustical foam, acoustic panels, and even curtains.

For those of you looking for cheaper solutions, you can build your own DIY absorption panels, or hang thick blankets up on your walls. Anything that will help “soften your walls” enough so that you can reduce those reflections from happening. This will help contain them to a degree and reduce the amount of reflections that will bounce out to your neighbors.

If you think about the way a church has the tendency to echo a lot, this is because church walls often don’t have softer materials on their walls to stop that echo. The sound just bounces around on the hard surface.

If this helps you better to visualize it, think

about a rubber bounce ball. It’s easy to bounce the ball off a wall or a floor–hard surfaces. However, if you try to bounce the ball off of a softer material like a heavy blanket, it becomes a lot harder for it to bounce. It doesn’t necessarily stop the ball from bouncing, but the energy of the bounce is greatly reduced.

The same principle can be said about sound as well when it comes to sound absorption.

Now, sound absorption is really great, especially for walls, ceilings, and takes care of those mid to high frequencies, but let’s talk about the bass and wall corners real quick.

Remember how we were talking about how bass frequencies have a lot of energy?

Since they have a lot of energy, it’s not uncommon for bass frequencies to build up in the corners of your room. To help reduce this build up, there is a sound absorption solution to this.

Bass traps.

Bass traps are a lot thicker for sound absorption, often looking like wedges for the corners of your room. This is again, due to low frequencies needing more of an air gap in order to reduce that energy. So if bass build up is a concern, consider getting a few of these or try DIY’ing them if that’s your thing.

Now, having said that, would I personally go all out and completely cover my entire room with nothing but acoustical foam? Ehh, probably not if I’m being honest. Sometimes it is nice to have a little bit of reverb in your room. Also, that would end up being something entirely out of my budget at that point. However, having some form of sound absorption will still help reduce those overbearing frequencies that would drive your neighbors up the wall. So I say yes, go for the amount of sound absorption that is right for you and your situation.

Now, I do have one last bonus tip for you all.

Keep in mind that sound has the ability to easily escape through the gaps underneath doors and through windows. With that being said, there are sound absorbing solutions to that.

For example, to sound dampen a door, you can place a door sweep to help reduce the amount of sound that gets passed underneath. You can also place a blanket on the door as well in order to reduce that sound from escaping. For windows, you can try using curtains as well as acoustic sealants in order to provide some form of sound absorption.

Just be sure to get any permissions needed before you make these changes if you’re renting, and that they’re up to the fire codes and regulations.

So! With that said, I’m sure there’s a lot more information out there on soundproofing vs. sound absorption, but hopefully this has helped you with some of the basics and differences between the two.

So for today’s question of the day:

Have you tried to sound dampen your room? If so, how did you do it?