It all depends upon who you ask, you might say. Rock concerts are notoriously very loud and the audiences like it that way.
However, in a small public park like the Franklin Powell Sr. Park in Cruz Bay, where we hold the St. John Arts Festival Food and Craft Fair each year, “too loud” can mean that the visitors to the fairs cannot communicate with the vendors and vice-versa when the bands in the bandstand are giving daily concerts.
It was Lord Kelvin, the British scientist, who said something like: “To resolve any physical parameter issues it is important to measure whatever you are arguing the toss about.”
For example, I say “That is one foot long,” and someone else will insist that it is eleven inches. So, for sound, I purchased a sound level meter and looked up acceptable sound levels established by such agencies as the EPA, OSHA, ANSI and NIOSH, also a paper published by the House Ear Institute which addressed the subject of Noise Induced Hearing Loss (NIHL).
To cut to the chase, it seems that hearing damage usually affects the mid-frequency range of the ear, causing what is termed a “noise notch” which affects the consonants of speech such that a person finds it hard to understand what someone is saying.
Different regulating agencies have established different decibel levels for specific time periods of exposure to sounds levels which would be safe for the human ear. The EPA is conservative in providing a bigger safety margin than say OSHA. For instance, prolonged exposure to sound levels above 85 decibels can apparently cause permanent hearing loss. NIOSH says 85 decibels for up to eight hours maximum is okay. The EPA says 85 decibels for up to 45 minutes maximum is okay.
With these guidelines in mind, sound levels were measured at the food and craft fair booths nearest the bands. Peaking at 85 decibels was found to be satisfactory for all concerned. Average levels were in the 75 to 79 decibel range.