This is the second in a series of blogs about why audiologists are terrified of musicians. Actually, we are not terrified of musicians- merely working with musicians!
This is a continuation of last week’s blog about using different jargon. Let’s turn our attention to intensity and loudness. Actually, for those purists out there, I am misusing “intensity”. Technically we audiologists should be using “sound level”. Intensity is a strange beast that has different units than sound level and is a vector quantity implying direction. But that’s another issue. Since the vast majority of my colleagues use “intensity” to mean “sound level”, we will use the two terms interchangeably here…
A musician reports that during practice the music is played at a mezzo forte level but that it can range from pianissimo (pp) to forte (f) and even louder (fff). Audiologists really only like to deal with intensity and not loudness, while musicians only care about loudness.
This may not seem like an important issue, but depending on the instrument there may be a loudness/intensity mismatch, especially for the bass instruments. This may lead to some counseling issues. Bass instruments such as the tympani, bass, and cello can have very low-frequency fundamental energy. Because the bass and the cello are half-wavelength resonators, the first (and sometimes second) harmonics are within the same critical bandwidth such that an increase in bandwidth does not necessarily correspond to an increase in the perception of loudness.
Audiologists love to talk about dBA weighted sound levels (or intensities), and while as a rule of thumb an increase in intensity implies an increase in loudness, the two phenomena are not the same animal. This is further complicated by the fact that some musical instruments have a formant (or inherent frequency range that is near resonance regardless of the fingering or note played). A flute has this “fat part” around A(880 Hz)- one simply cannot play this note (just above the treble clef) softly, yet if the music calls for it to be played piano (p or pp), then arguments can ensue.
This is a relatively minor area, but one that may rear its ugly head when you are counseling musicians.
We of course want to educate musicians about sound levels in dBA, since this has a high correlation with permanent hearing loss. Yet it’s amazing how quiet 85 dBA sounds. It’s a dial tone on a telephone or the sound level of flushing the toilet with your head in the toilet bowl. No musician in the world would consider 85 dBA (or even 90 dBA) to be all that loud. Symphonies frequently in exceed 100 dBA and rock concerts can come in around 110-115 dBA. So, there is an inherent mismatch between the audiologist and the musician about what constitutes “loud”.
Much of what audiologists do with musicians is counsel and provide information. Fear of not having the same playing fields is one of many reasons why an audiologist may be afraid or at least will think twice about working with musicians.