Bass Traps vs Acoustic Panels: What’s the Difference

There is no easy way to settle the bass trap vs acoustic panel comparison! It is best to understand what each of these acoustic treatments regales to and how they enhance the sound in a room. 

The difference between bass traps and acoustic panels is in the sound frequency ranges that they treat. Acoustic panels keep mid to high frequencies in check whereas bass traps treat low-frequency sounds. A properly treated room always incorporates both acoustic panels and bass traps for a balanced, clear, and distortion-free environment!  

Both of these treatment options have very different uses and applications. This is why their placement and usage need a better, more detailed explanation. 

Acoustic Panels – What Do They Do? 

Acoustic panels are rectangular panels made to hang/stand at reflection points of a room to absorb all high-frequency sounds. Reflection points are the angles on a hard surface where sound from the source emitters, e.g., speakers and/or monitors, hits directly and bounces back into the room. Such “bounced off” (reflected) waves interact with other sound waves on their way and create noise before they’ve reached the listener.  

This is when you need acoustical absorbers! They sip in such waves at these reflection points and eliminate echoes and reverberations. Their main purpose is to decay the reflected waves at a much quicker rate so the listener only receives the original sound/direct sound. Highly absorptive materials such as fiberglass, foam, or mineral wool are used to compose acoustic panels. 

They only work if laid in a strategic manner around the room to catch all the high or mid frequencies coming their way. You can counter sound issues such as flutter echoes, comb filtering, standing waves, and room modes with their absorptive properties.

The best part about acoustic panels? They won’t make your room ugly with heavy, foamy fronts. Instead, acoustic panels are covered in permeable fabric that not only allows the passage of sound waves to their cores but also adds sophistication and beauty to the room. You can paint the fabric or keep it at its minimal to match the room’s aesthetics.  

Bass Traps – What Are They? 

Bass traps are physically the same as an acoustic panel but thicker, denser, and relatively less pleasing to the eye. In a room without bass traps, everything you hear below 300 Hz is heavily distorted. This is due to multiple levels of acoustical chaos caused by slow-decaying sound waves.  

High frequencies have shorter wavelengths and require only a 2″ to 4″ thick panel to completely decay. Lower mid or low-frequency ranges have a different story!  

Low-end frequencies have very long (around 17 meters) and strong wavelengths. This means that you will need more layers and denser material to absorb these wavelengths.

Now, what are bass traps? How do they work? And how do they balance these long wavelengths?  

To simplify the physics here, when you turn on the sound source emitter you fill the room with motion energy. What happens is that such low frequencies build up along every hard boundary such as walls, doors, tables, or ceiling. But they tend to intensify where two hard surfaces come together and meet, i.e., the corners! 

When you place bass traps in corners, they interact with the kinetic (motion) energy of air (carrying sound waves) and slows it down via friction. The friction then produces thermal energy/heat to conserve the total amount of energy brought in by the air.  

This transition reduces the strength and intensity of waves. These dampened waves resultantly mitigate or eliminate that muddy or punchy feel from the sound.  

Hence, bass traps have the right properties, like gas flow resistivity, to bring peaks down and valleys up just by inducing the loss of amplitude of interfering waves. They can dramatically change the one-note, warbled, or booming noise into a clear sound without losing any of its bassy impacts.  

Difference Between Bass Traps and Acoustic Panels 

It is almost unfair to conquest bass traps vs acoustic panels without completely understanding how they differ from one another.  

Almost every room requires a combination of both bass traps acoustic panels to repurpose and absorb a range of frequencies in the room. The size and shape of the room also affect the kind of treatment that’s more suitable. For instance, a small room would deal more with low-end frequency issues compared to mid or high-frequency misbalances.  

However, there are three major differences between acoustic panels and bass traps. 

Purpose  

Keeping this one short (as already discussed briefly before), the main purpose of acoustic panels is to reduce noise. They also reduce slap echo, reverberations, control comb filters, and eliminate residual sound. These panels attend to late/residual and first reflections to ensure the listener hears direct sounds only.

Mostly, music studios, home theatres, restaurants, clubhouses, and every place where there are speech intelligibility issues use acoustic panels. You can install them in any space to achieve sonic clarity and stability. 

On the other hand, bass traps have a similar purpose. They work on the principle of sound absorption as well, but their main motive is to flatten the low-frequency response. They can absorb below 80-100 Hz and are effective to as low as 30-40 Hz.  

Placement  

Ideally, acoustic panels are supposed to go on your flat surfaces, reflection points, ceilings, or wherever the frequencies will be bouncing around in the room. 

Moreover, you’d want to cover all the problem areas completely in perfect symmetry. Target covering almost 20% of your wall’s surface area with standard 2ft by 4ft panels. Acoustic panels should be hung at your eye level for the best results.

This means different spaces will have different placement requirements. For example, in an office where people are mostly sitting, acoustic panels will work efficiently if placed lower, around 4-5ft off the ground.  

Similarly, center the panels at 5-7ft high to do their best in places where people usually stand, e.g., bars. With the right placement, they will capture the loudest, most direct waves that’d otherwise bounce around. 

Where to place bass traps? They deal with low-end frequencies that interact with hard surfaces just like waves of water that tend to build up and fill corners. You need to place bass traps in every corner of the room at a 45-degree angle. Try to minimize every 90-degree angle in your room to get all the excess bass clogging up your space. 

For back wall panels, it is advised to leave an air gap between the wall and the panel for better absorption. You can place them at a tri-corner (where a wall meets the floor or the ceiling), wall/wall corner, or the ceiling. 

Design 

When it comes to design, both bass traps and acoustic panels have unique models. Acoustic panels are backed with wood that helps to catch all the high/short frequencies. You can get fabric-covered, art acoustic panels, minimalistic contemporary ones, foam, or perforated wood ones. Acoustic panels take the lead with more options here!

They are usually 1,2, or 3” thick where a 1” panel would provide better absorption for high-frequency ranges and so on. The ultimate game-changer in this case still remains the placement of these panels. 

Bass traps are rather “backless”, which is why it’s best to leave an air gap between the bass trap and the wall for better absorption. The gap will attenuate built-up frequencies and provide an additional low-frequency absorption coefficient to the panel. Ideally, the gap between bass traps and the wall should be 16″. 

The design also includes thickness, a 3” absorption material loses its efficacy at around 250 Hz, whereas most of the low-end problems start occurring below 150 Hz. This is why you need a combination of airspaces, membranes, and extra thickness, 6” or more, to extend absorption properties.  

Bass traps are made from a dense, more porous material. They can be as thick as 18-24” (starting from 4” minimum) to take long wavelengths of sound in completely. They typically use industry-standard 6-pounds per cubic foot compressed all the way down to make a dense core. 

Corners of a room may sometimes get 6 dB louder than the rest of the room if left untreated. This is why you need thicker material there to avoid standing waves there. 

How Do I Know What My Room Needs? Comparing Acoustic Panels vs Bass Traps

Once you reckon what each of these treatments does, you’ll be able to decide whether you need bass traps or acoustic panels in your room. The main purpose, both acoustic panels and bass traps serve is noise reduction. They both reduce, correct, and balance noise in a closed space.   

Generally, if you want to treat sound resonance, flutter echo, and reverberations in a room, or simply just want a peaceful atmosphere, you need acoustic panels. Places that require the utmost concentration and comfort of their occupants are the most suited users of such treatments. This includes libraries, churches, restaurants, studios, etc.  

What if you’re recording a song or mixing sounds, would such a room need acoustic panels or bass traps?  

If you need to attenuate low frequencies, control room modes, or other acoustic interferences, you need corner bass traps. Auditoriums, theatres, listening rooms, and recording studios specifically require bass traps to balance extra bass. 

What’s Better? Bass Traps or Acoustic Panels? 

Rather than pitching acoustic panels vs bass traps, a more practical approach is to figure out and target problem areas of your room. 

When acoustically treating a room, both acoustic panels and bass traps should be used in a combination! Thin acoustic panels work best when coupled with dense, foamy bass traps in the corners to get a superior sonic experience. 

Summarizing it, a few things to keep in mind for best utilization of both; 

  • Define purpose, why do you need to acoustically treat your room? 
  • To control mid to high-end frequency ranges, use acoustic panels! To accentuate low-end frequency issues, use bass traps! 
  • Placement strategy! Bass traps or acoustic panels neither will do you any good if you don’t place them the right way. 
  • Proper thickness of the panels, air gaps, spacing, symmetry, and the appropriate number should be considered.