Should You Flush Mount “Soffit Mount” Your Monitor Speakers?

If you walk into any professional studio you will see large studio monitors built into the front wall. This is known as flush mounting and incorrectly termed "soffit mounting" as well. In this article I will go over the pros and some cons to flush mounting your speakers so you can decide what is best for your situation. 

1) The Pros To Flush Mounting Your Speakers

There are numerous benefits to flush mounting your speakers into the front wall. Here is a list of what we will go over in more detail. 

- Eliminate Diffraction At Speakers Edges

- Eliminate SBIR on Front Wall

- Increased Low Frequency Efficiency 

- Improved Stereo Imaging 

A) Eliminate Diffraction At Speakers Edge

The acoustical term diffraction refers to how sound interacts with edges of furniture, partitions and in this context the edges of your loudspeakers. The mid to high frequencies coming from your loudspeaker spreads out the front in 180 degrees. When those waves meet the edges of your loudspeakers they immediately propagate outward in a new direction. As Philip Newell states in his book Recording Studio Design, " 'diffraction' is particularly problematic at the sharp edges of small loudspeaker boxes, where the edges can act like independent sound sources." (Philip Richard Newell, 118)

The term independent sound source is very important because you can almost imagine diffraction as having new little speakers on all of your speaker edges pointing towards your front, and side walls. This leads to more phase issues if not absorbed properly. 

The picture below from coastalwiki.org is a great example of diffraction in water. Sound and water behave very similarly, so this is a good way to visualize the sound waves bending around your speakers. 

Photo Credit: Google Earth and coastalwiki.org.

This is all to say that if you flush mount your speakers in a rigid and dense wall then diffraction will no longer be an issue in your room. 

B) Eliminate SBIR off the Front Wall

SBIR or Speaker Boundary Interference Response is an acoustical term that refers to the soundwaves hitting a surface in a room and reflecting back to the listener. The reflective sound waves arrive after the direct sound waves creating phase problems in the room. 

The biggest issue with SBIR with loudspeakers is the low frequency radiation off the front wall and back to the listening spot. This causes dips and peaks in the frequency response of the loudspeaker which can lead to hearing too much or too little bass in your mixes. This then leads to over or under compensating in the mix or master leading to bass heavy or bass light mixes. All of this is undesirable in a control room.

Flush mounting your speakers in a heavy dense front wall means the bass frequencies are only radiated forward into the room. This means you will hear the direct sound of the bass without reflections (assuming the rest of your room is heavily absorbent at low frequencies) and make accurate decisions when recording, mixing and mastering in your room. This then leads to mixes that translate everywhere and speeds up every part of the production process. 

C) Increased Low Frequency Efficiency 

When you flush mount your speakers you are essentially extending the front baffle of the speakers from the left to the right wall. This leads to an increased efficiency in the monitor system leading to as Newell points out, "greater low-frequency efficiency of between 3 and 6dB compared to the same loudspeakers free-standing." (Philip Richard Newell, 381)

This means that the less electrical power is needed, which leads to less heat in the voice coils, "which tends to both reduce power-compression and distortion, and improves the transient response of the system at high SPLs. (Philip Richard Newell, 381)

Although, this is a very technical benefit, it nonetheless is important to mention since better efficiency of the system leads directly to a more accurate monitoring environment. 

D) Improved Stereo Imaging

Newell finally states that flush mounting your speakers in very heavy rigid boxes inside a heavy rigid wall will reduce any speaker movement due to high SPLs of low frequencies. I will be honest, I can't imagine this happens on smaller home studio monitors, but I could be wrong. Nonetheless, it is another benefit to flush mounting your speakers. 

2) The Cons To Flush Mounting Monitor Speakers

Not everyone should jump right into flush mounting your speakers. Below is a list of reasons not to flush mount your speakers. 

- You have low quality near field monitors

- You have not addressed low frequency absorption in your room

- You don't know how to properly flush mount your speakers

- You plan to move soon and want to take your studio with you

A) You Have Low Quality Near Field Monitors

Not all monitor speakers are built the same and many entry level monitors in the 300-1,000 dollar range probably should not be flush mounted. First, near field or close field monitors are built to be placed on a desk or speaker stands close to your listening position. They are not designed to be flush mounted in a wall. Second, because these speakers are entry level they do not have the fidelity and accuracy that higher quality monitors have. This means they are great for getting started, but are not worth keeping once you are ready to upgrade. If you are thinking of flush mounting your speakers you should also be producing, mixing and mastering at a high level or at least have the budget for high level speakers and room acoustics. 

I would recommend using mid field or far field monitors for flush mounting and making sure they are the best you can afford. Three way speakers that go down to 20-40 Hz are a must and they should have little distortion and a flat frequency response. You should also love your monitors because once they are in a wall you cannot easily swap them out. 

B) You Have Not Addressed Low Frequency Absorption in Your Room 

Before you flush mount your speakers you must also have a plan for properly treating the rest of the room. You need to have absorptive walls and ceilings that goes down as low as possible. This means building custom diaphragmatic acoustic walls or using thick insulation panels with big air spaces behind them. It also means treating all surfaces of the room especially corners. 

If you are still working on getting your room acoustics right then flush mounting should wait too. 

C) You Do Not Know How To Properly Flush Mount Your Monitors

If you search "flush mounting monitors" on the internet you will get a lot of answers. I have read almost all of Philip Newell's books, but he does not give his secret away on how to flush mount speakers. This means there is an element of DIY when it comes to wall mounted speakers. Be prepared to do research and design a plan before you jump into flush mounting. You can always hire a studio designer as well. 

D) You Plan To Move Your Studio Soon 

The beauty of home studio design is that much if not all of the room acoustics can be moved from room to room. Acoustic panels, free standing speakers and free standing bass traps all mean you can load them up when you move. If you flush mount speakers you will leave a big gaping hole in your wall when you leave. The next owner will have to have your same speakers or tear down the wall. This might be the biggest reason not to flush mount your speakers. So many of us want pro results, but we are in home environments. We can get great results with basic home acoustic principles and a lot of times that is where you should stay. 

Conclusion

I will be honest, I am really interested in flush mounting my speakers and building a Philip Newell style control room. In fact, my next home studio will be just that. However, like many of you I am stuck in where my knowledge was when I built my first studio. I could try flush mounting my speakers, but I wonder is it worth the cost, how long will I own this house and what would the resale value be. On a deeper level I think all of us are constantly torn between wanting better results in our home studios and reality of home studio limits. 

If you are building a professional studio that needs to compete with the best studios in the world, yes definitely flush mount your speakers. If you have great monitors and a great room and want to take it to the next level, yes flush mount your speakers. If you are curious and just want to see what happens, yes flush mount. 

But, if you see the cons as outweighing the pros then maybe wait and keep working on tweaking your listening position, tweaking your room acoustics and saving up for better monitors that you will never have to sell. 

 Works Cited

“File:WaveDiffraction.jpg - Coastal Wiki.” Www.coastalwiki.org, www.coastalwiki.org/wiki/File:WaveDiffraction.jpg. Accessed 15 Mar. 2024.

Philip Richard Newell. Recording Studio Design. New York ; London, Routledge, Taylor & Francis Group, 2017.