The sound of silence

I still vividly remember the day a decade ago when my then 10-year-old daughter Michelle asked me if there was such thing as a sound we could not hear.

Her curiosity could have been aroused by Simon & Garfunkel’s hit song Sound of Silence, which I was intently listening to when she invited herself to my music room to goof around.

My answer was met with a wide-eyed gasp. She couldn’t believe when she heard me say that, yes, there are sounds that are beyond a human’s auditory limit, but that we can see them! I told her that the oscilloscopes and real-time analysers (RTA), both electronic devices that measure sound wave, could do the trick. We could view on their respective LCD screens the sounds that are otherwise aurally silent via the sine waves representing each frequency of the music we’re hearing.

The literal meaning of the sound of silence may lack the prose and beauty of the song, but it is nevertheless essential to us audiophiles. Humans can only hear sound waves between 20 Hz and 20 kHz. Anything below and above that, we leave to our more hearing-sensitive canine friends. There are also sound waves that cancel each other out. This is the reason we cannot hear two sound waves of the same pitch and decibel.

The two sound measuring devices are also the key to how my good friend, audio engineer John Alegre, and I tune sound systems. System-tuning is just one of the services (aside from designing speakers) that our company, JV Audio Concept, offers.

The sound system you buy at your favorite dealer will, more often than not, sound differently when it is finally set up either in your living room or in your dedicated music room.

At JV Audio Concept, the sound you hear is dictated upon by the acoustic design of the room where your system is going to be placed. Hostile sound acoustic (such as when the room is surrounded by glass, or it has an asymmetrical physical design) can be tamed. Oscilloscopes and RTAs can measure the extent by which your room should be treated.

Sometimes, the solutions are simple. Just placing your speakers at the spot where sound comes out exceptionally well from your listening position solves the problem. Based on our experience with several clients, however, the solutions are oftentimes radical and require the intervention of acoustic treatment modules.

We have partnered with acoustic expert Tony Rodriguez for the use of customized natural wood acoustical wall panel and suspended acoustical ceiling systems which can complement the architectural design of your home. Aside from their aesthetic appeal, these treatment modules house potent acoustic tools that can lessen reverberation time, eliminate flutter echo, limit unwanted sound reflection and provide noise control in a wide variety of spaces.

The easiest way to control wayward sounds is to use an equalizer. If you’re not too squeamish about using one (purists loathe the use of the device), you must at least know which part of your room is causing the problem. Unfortunately, doing this is not plain guesswork. It requires precision which can be achieved through the correct use of oscilloscopes and RTAs. Equalizers can either clip or add on frequency level, thus giving you the freedom to get the right amount of sound that your room needs.

There are two ways, albeit unconnected, by which aspects of acoustic treatment can be used. One is sound isolation. With this, we try to minimize the seepage between rooms, and between the inside and outside of a room. The other, which this column is all about, is treating the room itself to lessen reflections that give life to reverb, echoes and standing waves which can make even the most brilliant music frustratingly murky.

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For comments or questions, please e-mail me at audioglow@yahoo.com. You can also visit www.wiredstate.com for quick answers to your audio concerns.