By Jack Sharkey, August 27, 2014.
In a perfect world, my listening room would consist of a 2-channel monoblock system driving a pair of Blades, a $9000 turntable, a chair with a cupholder, and proper acoustic treatments all around. I would lock the door from the inside and emerge only for more beef jerky and occasional visits with my family.
I don't live in a perfect world.
I do however live in a world that can be quite aurally satisfying with just a few minor adjustments.
With the release of our new Reference Series speakers, our engineering department has put together a seriously detailed White Paper that covers not only design for The Reference, but in-depth discussions of general audio topics as well. Much of the information in this piece came from that document.
Things You Can't Control
Regardless of how hard you try, you will never be able to eliminate the effect your room has on your audio. However, with a little experimentation you may actually be able to use your room to your favor.
The positioning of your speakers relative to your listening position is probably the most important factor you need to take into account when setting up your listening room, so start with the physical set-up of your speakers and listening position before you worry about anything else. You just may be amazed at the differences in overall sound quality just a few inches can make.
In the figure below, the positions of two loudspeakers were changed by only 1 1/2 feet (.5m) relative to each other, but you can clearly see significant differences in how the speakers responded. The clearest example of this is in the frequency range right around (and above) 90 Hz.
This figure clearly illustrates the need to experiment with speaker placement within your room. Many times blame is laid on lack of amplification or bad loudspeaker performance when a simple movement of even a couple of inches in speaker placement can make a world of difference. While there are no one-size-fits-all suggestions because of all the variables (room size, decor, surfaces present, amplification, source, etc.), there are a few guidelines you can follow that will make your listening experience even better (with a little experimentation and patience).
Bear in mind, that the first guideline you should follow is what your ears tell you. At the end of the day, the only thing that really matters is that you like the sounds you are hearing. There's a lot of science involved in audio, but trust your ears to be the most precise listening instrument you will ever have access to!
General Loudspeaker Positioning Tips
The figure below will give you some basic tips on speaker positioning:
Ten Tips For Positioning Your Speakers
1. Your speakers should be between 6 and 12 feet apart, with a wall behind them, and the prime listening position should be the same distance from the speakers as the speakers are apart – forming an equilateral triangle. Of course, with KEF's Uni-Q technology, the "sweet-spot" for the best stereo image is broadened considerably, giving you a wide range of "sweet spots" in your listening room (Why So-Called 'Co-Axial' Speakers Aren't Uni-Q, KEF Blog, 7-30-14) but it's good to have a baseline to start from.
2. For best low-frequency response, experiment with the distance of your speakers from the front wall (the wall behind the speakers). The typical optimal distance is between 1 and 5 feet and the rear of both speakers should be the same distance from the front wall.
3. Try to have the listening position as far away from the rear- (or side-) walls as possible.
4. For optimal stereo imaging the left and right side-walls should be the same distance from the loudspeakers and the surface should be made of the same material.
5. The optimal distance to the side-walls from the speakers is around nine to ten feet (experiment!). Proximity to the side-walls can create an imbalance in the timbre of the speakers, but conversely, a complete lack of interaction with side-walls may result in a very small stereo image.
6. If you are going to acoustically treat your room, think diffusion instead of absorption. Absorption may quiet some reflections but it may do so at the cost of making your room sound dull and lifeless – a little reverberation or "liveness" is a good thing!
7. Toeing in the speakers may help with high-frequency response and the perception of the stereo image (make sure you toe both speakers in exactly the same). With KEF's Uni-Q, balance doesn't suffer as you move off-axis (off the equilateral triangle) so keeping the speakers flat (not toed-in) may actually be an excellent solution for rooms that are too lively. You may want to try it before you invest in acoustic treatments.
8. Make sure your distances are equal. Use a tape measure. Your brain is very sensitive to differing arrival times of sound to your ears.
9. Bass traps can help if they are done right. Bass traps can do wonders to increase low-frequency response in your room, but a bass trap that is not constructed correctly, or is not the right size, can actually do more harm than good. Remember that in a standard room there are twelve corners, not just four, that can affect your bass response. A bass trap that is effective on frequencies below 80Hz typically needs to have a volume of 15 cubic feet, so yeah, that could potentially take up a lot of room in your room. You may actually get away with more bass, cheaper, by adding a second subwoofer!
10. If you're still not happy, you may need to start with a different approach to your set-up. Change your room around. Listening position is just as important as speaker position, and the elements and surfaces in your room play a huge role in how your room sounds as well.
For more information, please check out our White Paper on our new line of Reference speakers.
The opinions expressed in this article are the author's own and do not necessarily reflect those of KEF or its employees.