Why should one bother trying to understand basic acoustics? The most simple (and correct) answer is that study of basic concepts enables one to sort through the truth, semi-truth, myths and flat-out errors that pervade the pro audio industry.
The fundamentals of acoustics (and physics) do not change, although some “experts” try to prove otherwise. New equipment, toys and theories come and go, but the basic building blocks of sound and its related concepts do not.
If university level training in audio or acoustics is not your calling, don’t despair. There are many excellent seminars sponsored by industry, manufacturer, trade, and commercial organizations that can further your knowledge.
And did I mention books? There are numerous excellent texts available that cover almost every topic imaginable in acoustics, sound and systems. Do some web surfing—you’re certain to come upon valuable and useful educational resources.
Further, on-line training courses are abundant, and some are quite good at covering the basics. Intensive educational seminars, such as those provided by SynAudCon, can be invaluable if you have a few days each year to devote to this worthwhile pursuit.
In the meantime, let’s start with a look at some of the bedrock concepts that can put you on the path to higher understanding.
Passage of Pressure
Sound is related to the sensation of hearing and the generation of vibrations that results in a physical disturbance evoking the sensation of hearing. Briefly, sound is the passage of pressure changes through an elastic medium via wave propagation caused by vibrational forces acting on that medium.
Acoustics is the study of sound transmission through fluid and solid media. Noise is unwanted sound. But as some have said, one person’s sound is another’s noise.
Sound can be described and quantified in a variety of ways based on wave motion, pressure, particle velocity, transmission medium density, wavelength, and frequency. A medium is necessary to transmit sound.
Sound can travel quite readily through solids, liquids, and gasses. The transmission medium has an affect on the propagation of sound, particularly its characteristic velocity.
Sound originates from a source (vibrating body), propagates through a medium (solid, liquid or gas), and is picked up by a receiver (listener or microphone). This is commonly called the source-path-receiver model for sound propagation.