| Isn't it amazing how much sound we're bombarded | | | | retreat to a place of soundproof solitude are the low |
| with everyday? We love to find a quiet moment | | | | frequencies below 125Hz. This is the realm of the |
| where we are not acoustically assaulted by people, | | | | worst sound of all. |
| equipment, traffic, stereos, neighbors, cell phones, | | | | There would seem to be a need to set standards |
| and on and on. It's hard to find that quiet moment, | | | | for healthy living that describe how to insulate |
| and perhaps even harder to find that soundproof | | | | yourself from such noise. In fact, there is a standard |
| place. Sound levels are so intense that many walls | | | | that measures a structure's ability to hold back sound. |
| and building materials just don't stop the sound | | | | It is called STC, which stands for Sound Transmission |
| satisfactorily. | | | | Coefficient, and is the most recognized and discussed |
| Think of it. How often are you bothered by noise | | | | sound isolation term in North America. |
| from the person in the room next door, even though | | | | Building codes will dictate what STC level a building |
| the door's shut? Have a music student in the house? | | | | needs to have. A new condo, town home or |
| Dad like to watch movies late at night? How about | | | | apartment will have to comply to these building codes |
| the neighbors having yet another party? | | | | and build walls, ceilings and floors that meet these |
| How in the world do we cope? It's no wonder that | | | | STC requirements. If this is so, how come I can hear |
| Ben Affleck slept in a soundproof sensory deprivation | | | | my neighbor? Why is my new condo so noisy? After |
| chamber in the movie Davedevil. But of all the noise | | | | all, the structure is built to code. |
| that we retreat from there's one that's the worst of | | | | The reason that new structures are still noisy is |
| all. Bass. It's the worst because it's the hardest to | | | | because of the STC standard itself. STC does not |
| stop. In the acoustics industry, "bass" is known as | | | | measure any of the worst sound of all. It stops |
| low frequency sound. It's the boom-boom music | | | | measuring at 125Hz... exactly where the worst sound |
| sound you hear coming up behind you while driving. | | | | starts. So you have a high STC wall that meets |
| You hear it long before you see the car that's | | | | code, but sounds terrible. Great. |
| creating it. Low frequencies are the jets flying | | | | There is a need to change this STC standard to |
| overhead if you're near a major airport. | | | | include these low frequencies. They do this already in |
| This is the worst sound of all because it assaults | | | | Europe and Australia. In the meantime, what can you |
| from long distance. It penetrates normal building walls | | | | do? |
| and ceilings. Low frequencies are the largest and | | | | Look for building techniques that have been tested |
| generally the most powerful sound waves we come | | | | below 125 Hz. Good performance below 125Hz. will |
| up against daily. They are hard to escape. | | | | help you a lot. Be aware of products like resilient |
| Paradoxically, the low frequency "bass" is what is | | | | channel, "sound" boards, foams, tapes, clips and |
| being sought more and more in home theaters, | | | | especially mass loaded vinyl (MLV). These products |
| bands, and music systems. So our dilemma is only | | | | won't help you in these critical low frequencies. |
| going to get worse. | | | | Consider materials that "damp" the sound vibration. |
| The "volume" level of sound is measured in Decibels | | | | These types of products are generally known as |
| (dB). The frequency of sound (bass, midrange, treble, | | | | visco-elastics and are most effective with the worst |
| low notes, high notes, etc) is measured in Hertz (Hz). | | | | sound of all. |
| The sounds that are most problematic when we | | | | |