Heading up this month’s “Why didn’t I think of this?” department a few readers sent in an excellent idea in response to our recent tip on subwoofer placement (see inSync 7/17).
This is so obvious once you think of it. Room modality has the biggest impact on the perceived frequency response of a sub. Here’s a way to use this phenomenon to your advantage. Place your sub at your preferred listening position and play back some “reference” music through it. Reference music is just music that you know well enough to make accurate qualitative assessments. You can also use a test CD that provides full bandwidth and band-limited pink noise. The band-limited noise can be useful for letting you hear only what is happening in the low end. Our Sweetwater Reference CD has this.
Walk around your room listening to how the response of the sub changes. Each time you find a spot that sounds “right” mark it. You probably won’t find more than two or three. Now you have a limited number of specific places in which you can try your sub. Return to your listening position and try the sub in each of the places you noted. You may have to make adjustments to the level balance between the sub and your main speakers during these tests, but you should quickly be able to tell if it’s “right.” Of course the results of your mixes will give you a lot more information about that. At least it’s a more concrete starting point. Subs, even when placed perfectly, can sometimes cause problems (for many of the reasons mentioned in the 7/17 tip) so you have to be very careful about their use. I usually try to use less level on the sub than what I would normally think I need. But then it’s always a good idea to turn the sub way up occasionally just to listen carefully to what is going on down there. None of this is an exact science. You have to use your best judgement and learn the characteristics of the system you have.