Skip to main content

I get a lot of room forms sent in, I get a lot of phone calls and I get a lot of e-mails and people are what I call gear-proud. They’re proud of their gear. They’ve saved and they’ve researched and analyzed and they really get kind of emotionally attached to their gear and one of the particular things that they get attached to are speakers. And I understand that because the speaker is really the closest thing to the source of music that you’ll ever have, it’s the visual representation of the sound source.

But we have to be careful here. W e have to be careful with getting too close emotionally to our components and treating them like they’re the most important thing in the chain. And they’re not. They’re just another component. And if you really understood how they’re made and how they produce energy you wouldn’t elevate them to such a high point of concern and care, believe me, because they’re really imperfect devices. And there are so many variables as we all know from my past videos that contribute to sound quality but they’re just another piece of equipment in the chain, just like your amplifier, just like your cables, just like the room. All are components to producing good sound quality.

So let’s don’t get too close to our sources so to speak. So let’s be a little bit careful and step back a little bit and realize that the speaker is really just a sound generating device within our rooms. Now, that speaker must be compatible with the room size, volume and usage. So a lot of people buy big speakers because they think bigger is better and then they put them in small rooms which negates everything the designer intended when he designed the speaker. You have to be a little bit careful here with hero-worship so to speak and getting too attached to these things. You’ll have more enjoyment out of your system if everything is balanced and matched together, the speaker is not too large for the room, the amplifier is not too large for the speaker. There’s all kinds of balancing acts and ratios that we have to go by.

So speakers are just another sound source, just like my voice is to you in this video. It’s just another source governed by the laws of physics. Now, it’s a source that’s reinforced with electronic amplification but nonetheless it’s still a source and we can control the amount of energy we put in the room.

What are the big components of a speaker that we need to be considering? Low frequency driver size and diameter. That’s the whole key and the number. So the number of low frequency drivers we have in our speakers and their diameter. Because we know from past videos that the difference between a 10-inch low frequency driver and a 12-inch low frequency driver is plus 2 dB of energy.

So we like large speakers, a lot of us do, I hear it every day and I cringe every time I hear it because I know that just a 2 inch difference between a 10-inch and a 12-inch low frequency subwoofer so to speak creates 2 dB more energy. Now, most rooms have low frequency problems. So the larger the low frequency driver we have the more problems we have in the room. Not that only at the low frequency, middle and high frequencies also. Because we get too much energy that we have to manage.

So how can we control some of that? Well, we can simply tell the speaker electronically to not play a certain amount of energy at a certain frequency or below or above. And that’s one way to do it. I don’t like that way because I don’t like limiting the music source that the artist and engineer have put together because they have put together a full range presentation and if we’re going to go and cut off some of that electronically through a crossover I don’t think we’re doing our music justice. I would rather design the room, have the room compatible with full range music and go from there.

So realize that the speaker is full range and the most important part is the number of low frequency drivers you have. Middle and high frequency drivers are small by definition and most rooms we can handle that energy, the reflections through diffusion and absorption. But when you get oversized low frequency components in your speaker system just a 2-inch difference can make a 2 dB difference in energy that causes problems for all frequencies in your room.

So we have to be really careful and marry the size of the speaker to the room and the usage. So I know you like your monitors and your speakers and a lot of you are proud of the fact that you finally saved the money to buy these but be very careful. Make sure that the speaker works in the room that you’re going to use it in.

This is an unedited transcript from our video series from Acoustic Fields. There will be some errors in grammar and sentence structure that occur during this translation process.

For complete understanding and comprehension, please view the video which is included in this text. For any additional information regarding this topic or others relating to room acoustics, please contact us directly at:

P: 520 – 392 – 9486

Dennis Foley

I am an acoustic engineer with over 30 years’ experience in the business. My technology has been used in Electric Lady Land Studios, Sony Music of New York, Cello Music and Films founded by Mark Levinson, and Saltmines Studios in Mesa, Arizona, along with hundreds of others.


  • Peter says:


    I’d like to fill out the form so you can review my room, however, I’m not sure which dimensions to use. I am in the garage. Left & right walls are cinder blocks. It’s 39’ long, 10’6” Wide, and 8’ high. The ceiling is dry wal. I cut the room by putting up a 6” thick wall of absorption. 3” is 705 rigid fiber glas, and 3” is Rockwool Safe n Sound. So, the part that is the control room is 18 long, 10’.6” wide, with an 8’ ceiling. I appreciate the fact that when playing music, the low end barrels through the 6” made wall like a hot knife going through butter. When the sound goes to the other side, the garage portion, the sound then deflects and diffuses off all the stuff in the garage like lawn mower, shelves, and everything else in there… my question is, when measuring my room, do I use and send you the original size of the garage, or the control room size?

    Please advise



    • Dennis Foley says:

      P, Use the largest footprint (space) you have available for the project. If you are willing to demo out the space to make it larger, use the larger dimension.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.