Wherever you choose to place your high-performance home audio system, it’s going to sound very different there than in any other room. Even with a perfect setup, each room’s sonic signature is unique. That’s one reason why the same equipment never quite sounds the same in two different rooms.
You have two main options:
- Accept your room as it is and work with the space (perhaps compromising performance).
- Work with the room and try to mitigate some of its problems, turning liabilities into benefits.
If time permits, I prefer the second approach – using whatever tools I have to help get the best possible sound.
The best way to think about the room and your system is to treat them as a single entity, a pair of elements working together in tandem, rather than as antagonists constantly fighting against each other. If you think of them not as battling factions but as unwitting partners, you’ll have a much easier time bringing the magic of a high-end stereo system to life.
By analogy, think about a car and its motor. An automobile’s motor is a feat of engineering magnificence. Its sole purpose is to produce as much power as efficiently as possible – a thing of beauty when placed on the test bench. But saddle that motor with a few thousand pounds of dead weight from the automobile’s cabin, and it struggles and strains to do its work. To make a great automobile, engineers must work with coach and motor alike to fashion a single perfect unit. The same is true for an audio system and the room it is playing in.
Now that we have an idea of what we’re up against, let’s take a look at some of the more specific problems presented by the room/stereo interface.
Corners
Perhaps the worst place for sound in any room is the corners. The meeting of two walls forms a kind of horn that amplifies some frequencies but not others.
For example, stand in the middle of your room and start speaking, noting the tonal quality of your voice. Continue to speak as you approach the corner. Notice how the tonal balance changes: lower frequencies become exaggerated relative to higher ones. This sounds very unnatural – the exact opposite of what we want to achieve.
Because of this horn-like quality, you don’t want to place most modern loudspeakers in the corner (though some older speakers were specifically designed for it). Perhaps the most famous example is the folded corner-horn loudspeaker, the Klipschorn. All through the 1950s, dozens of US manufacturers licensed Klipsch patents, and hobbyist publications were filled with ads for “Klipsch patent horn” enclosures and kits.
But today’s modern speakers are not designed for corner placement. Unless you own one of those classics, stay out of the corners. Just remember: your stereo is your baby, and nobody puts baby in the corner.
The most obvious room corners are the points where two walls meet, but they aren’t the only corners you should worry about. Because rooms are usually longer and wider than they are tall, the longest corner surfaces are where floors, ceilings, and walls meet. These long junctions create a different problem: not an acoustic horn, but a reverberant slap-echo chamber.
To test this, walk the room and clap your hands near the boundaries. What you want to hear is a clean clap without lingering reverberant echoes. If you’re starting with an empty room, you’ll likely hear sharp, sometimes repeating echoes as you approach wall junctions. This is called slap echo, and it’s something you want to eliminate.
Often, adding a floor covering and furniture will mitigate slap echo, but some rooms need more. Floor-to-wall junctions are easy to work with – carpet, bookshelves, tables, and lamps will break up the echoes. Wall-to-ceiling junctions are trickier. A simple and effective solution is adding crown molding. This decorative angled trim reduces the sharp 90-degree meeting of wall and ceiling, cutting down unwanted slap echo – and often eliminating it altogether.
The PS Audio Listening Lab.
Furniture
The easiest of all room treatment methods is the use of furniture. The objects we loosely refer to as furniture can be divided into two main categories: absorptive and reflective.
- Absorptive furniture (couches, stuffed chairs, heavy drapes) reduces sound by converting audio waves into heat.
- Quick physics note: Sound is the ordered movement of air molecules in wave patterns. Heat is the disordered, random movement of atoms and molecules. Soft, porous materials – cloth, wool, fiberglass, foam – disrupt the order of sound waves. The waves get scrambled, rubbing against surfaces and creating friction, which turns sound energy into tiny amounts of heat.
- Reflective furniture (tables, wooden chairs, framed pictures, televisions) scatters sound without reducing its loudness.
Every great-sounding room is a careful balance of both absorptive and reflective surfaces. Too much absorption and the music will sound dead. Too much reflection and it will sound overly live and bright. Like most things, balance is the key.
Practical tips:
- In an overly dampened room with too much absorption, add reflective surfaces like pictures, wooden bookshelves, tables, or large vases.
- In a room that’s too reflective, tame it with absorption: pillows, cloth chairs, beanbags, folded blankets, or throw rugs.
These are just a few of the techniques you can employ to bring your room and speakers into harmony. I’ll cover more advanced room-tuning methods later.
