The best sounding systems I have heard are the ones where the acoustics are best. The room you listen in colors the sound and interacts in complex ways that I won’t discuss here, but your room has a very significant impact on the ultimate level of performance any given system can attain. Put an inexpensive set of speakers in a good room and it will outperform an expensive system in a bad room everyday of the week and twice on Sunday. I guarantee it.
When sound exits the speakers, only a small portion of it reaches your ear, untouched. The rest of the sound will reflect off the surfaces in the room, which can create a wild in-room frequency response and distort the sound before it reaches our ears. Some speakers interact with the room more synergistically than others, depending on how it was designed, but it is a good idea to have some level of acoustic treatment since the speaker designer does not know what room you have specifically. Acoustics are a complex topic, and I don’t claim to be an expert, however I do know that room treatment is an important part of a good sound system when the acoustics of the room are less than ideal.
Think of the room as a component of your system. Having a good sounding room will make any system sound better, no matter the cost. So what are the characteristics of a good room?
- Size
- Shape
- Materials in the room
The size of the room is important because if it is too large ( such as a theater, open floor plan house, or large living room), there will be too much surface area which will cause echoes (which is expensive to treat). Imagine being in a large echo chamber. Most people have the opposite problem. The room is too small (<1500 ft^3), which leads to bass energy buildup, distortion, and an uneven frequency response. All rooms have issues with reflections in the higher frequencies, due to the nature of the sound wave. An ideal room would be big enough to avoid the issues of bass energy buildup, without the excessive echo that comes from the large surface area of a larger room. Additionally, the l x w x h ratios ideally match up in a way that allows for the lowest notes of your speakers to propagate throughout the room fully before reflecting. For example, a 40hz bass wave is around 28 feet long, so having enough room to accommodate for the energy you are trying to pump into the room is ideal.
The shape of the room is important with regards to the corners. The corners of the room are where most of the bass energy builds up and so if the room has lots of sharp corners, this can cause resonances that create distortion and may be heard as “boomy”. As an experiment, take any speaker you own and put it in the corner of the room. The bass will be more pronounced than when it is in the center of the room. Some people purposely place the speakers closer to the wall to help with bass response, but the issue with this is that you are hearing a lot of reflected bass, and the bass may not be boosted equally at every frequency. Another aspect of room shape is whether there are hallways, overhangs, cut-outs, or other unevenly shaped parts of the room. This will lead to unequal reflection times, which are important for accurate imaging and a sense of coherence to the sound. If one speaker is jammed up against the wall near a hallway and the other is away from the wall in the center of the room, it is somewhat equivalent to listening with two different speakers. Taking care to create even boundaries, whether with furniture or dedicated acoustic panels, is an important part of making a room sound good.
Materials in the room are important because they each have different reflective and resonant properties. A carpet will absorb more energy than say, a mirror. Mirrors are highly reflective surfaces, as are windows. As an example, I tried placing a few towels over a mirror that was sitting between my speakers and was shocked at how different it sounded. Clearly, the reflections from the glass were negatively affecting the sound coming from the speakers.