How to test for acoustic problems in your room
TESTING FOR ACOUSTIC PROBLEMS
In previous blogs I have talked about the most common acoustic problems affecting rooms and how to take corrective measures. The only question left, is how you go about testing your room for these common acoustic problems? In this article we will cover some ways of testing for these problems.
The Hand Clap Test
If you have a good set of ears and some patience, there is a test you can employ that won’t cost you a penny, just some time. This test can help identify problematic sound reflections in your room.
The hand clap test: so named for obvious reasons. You will need to stand or sit as close the middle of your room as possible and clap your hands once, listening carefully to how the sound is affected. Do you hear a slow, even decay? Do you hear a single hard reflection? Or do you hear a multiple of closely spaced repeats? These faster echoes are known as flutter echoes and are created when sound bounces back and forth between two parallel walls or a parallel ceiling and floor. Flutter echo is something that you will definitely want to take measures to correct. One of the cheapest way to address the very serious problem is the use of diffusing methods. (this subject will be be covered in two weeks)
USING A SPL METER IN CONJUNCTION WITH A TEST-TONE CD
If you have a little money to spend, a very cost effective tool that you will want to pick up is a SPL meter. SPL meters are devices used to get an exact reading of your rooms sound levels. For most people the easiest way to effectively use this tool is to purchase a test-tone CD. To test your room, take your SPL meter and get as close to the middle of the room as you can, now start the test-tone CD, you will need to write down each number displayed by the meter. It will take around an hour or so to complete the room test. This test will give you a complete picture of your rooms acoustic responses. Now you know what problems your room has (if any) and what corrections to your room’s acoustics you will what to undertake.
If you have a big enough budget there are many high end testing devices and software on the market, just remember to do your research to find the best deal for your budget and needs.
In testing, one important point of information for all of you would be testers, is that each frequency has a different size wave length. How do you go about finding the size of the wave of a frequency? Here is a easy mathematically formula you can use to find the size of the wave of any given frequency: simply divide 1130 (sound travels at the speed of 1130 feet per second through air) by the frequency. As an example, a 100 Hz would be 11.3 feet and a 1000 Hz would be 1.13 feet. The rule of thumb: the higher the frequency the shorter the wave and the lower the frequency the longer the wave.
Next week’s blog: Room speaker placement. In order to deliver the best sound quality to the listener’s ear proper speaker placement is key. This is a no cost measure that even the non-do-it-yourself types can undertake to improve the listening quality of their room.