When designing or selecting a room for dedicated listening, the first and most crucial factor to consider is its physical dimensions. This single aspect can influence sound quality more than any other adjustment you might make. I’ve learned this lesson the hard way—more than once.

In my shop, the listening room I initially created had no engineering basis at all. From the start, I knew it would be acoustically suboptimal. My thinking was that it would be more insightful to evaluate our amplifiers in a less-than-ideal environment—closer to what most people experience—rather than in a perfect room, which few have access to.

As expected, the room was far from ideal, but it served its purpose well for about two years. However, the poor acoustics eventually became intolerable. After revisiting my Master Handbook on Acoustics, I was inspired to remodel the room, especially when I realized that I could adjust its dimensions to match one of the optimal formulas listed below:

Optimal Dimensions for a Listening Room:

Design Option A Design Option B Design Option C
Room Width 1.14 x Height 1.28 x Height 1.60 x Height
Room Length 1.39 x Height 1.54 x Height 2.33 x Height

The key element in my room was the drop ceiling. Above it, I had nearly an additional 12 inches to work with, allowing me to aim for a 9-foot ceiling height. This change, along with modifying two walls, was all that was needed.

I ultimately opted for Design Option B. I raised the ceiling height from 8 feet to 8.83 feet (106 inches)—as close to 9 feet as I could manage. The width was then adjusted from 12 feet to 11.3 feet (8.83 x 1.28), and the length from 22 feet to 13.6 feet (8.83 x 1.54).

Fig. 1 shows the original 12 x 22 listening room. Fig. 2 is a picture of the same room standing in the same spot. It has a 6-foot opening at one end, with the remainder of the original listening room just on the other side. Flanking the opening with a pair of speakers gives the soundstage almost infinite depth.

As you can see, the room was actually made smaller, yet the difference in sound is amazing. The two rooms can’t even be compared because the differences are so vast.

The results of this nearly perfect room were easily measurable, and it has elevated the sound of my stereo far beyond what it was before. In the original room, changes to speakers, amps, sources, cables, power conditioners, and tweaks didn’t make enough of a difference to be worthwhile when compared to the impact this new room made using the exact same combination of gear. To emphasize this point: imagine a man upgrades to a $4,500 source and experiences a 15% improvement in the overall sound of his system. Now, if we take him back in time and have him keep his original source but change his room to something like this, he would hear a 40% improvement in the overall sound of his system. Then, if we add the $4,500 source in the new room, he realizes it makes more like a 25% improvement—not just 15%. The end result gives him a 65% improvement in the overall sound of his system. The remodeled room cost around $1,000, including treatments. After spending many weeks with his new room and system, the man hears deeper into everything and discovers that certain cables he thought he liked he actually doesn't anymore, and so on. If you’re accurately going to judge a beauty contest, it helps to have 20/20 vision.

So study the formulas. See if adjusting a wall or ceiling a few inches or feet can put you into an ideal room dimension. Don’t worry about the room getting smaller or larger than it is now; it really won’t matter. As long as the room fits one of the three formulas, it will sound better than good.