As humans we apply subjective judgement to just about everything all day long. But I'll limit this particular discussion to sound quality.
"That radio has a good sound," for example, is something people often say about the C.Crane Radio Plus, that for several years served as the control point monitor for KDX Worldround Radio.
But at other times I have been displeased with the particular "EQ" or sound-curve and crossover between woofer and tweeter in this same radio. Does that mean that something has changed? Possibly yes.
Our own sense of hearing changes, to name one thing, based on a variety of biological, psychological and environmental factors.
A sound system that sounds fine while we're relaxed and well slept might not sound so good when under duress, fatigued or in a rush.
The radio itself might sound different in a different location or when various objects are placed nearby, all of which present reflections and standing-waves.
The problem is all the more compounded when trying to evaluate the sound of a microphone by using the voice as a test instrument monitored on the radio.
All of those considerations come into play here at Worldround Radio where I've been experimenting with self-built microphones since 1990.
At this stage I consider my own sonic judgement to be the weakest bit of test gear in the house, yet I'm the final judge.
While my subjective technical ability to listen critically hasn't improved much over the years, my storehouse of understanding the problem has become more detailed, as witnessed by this writing.
To put it another way, I'm full of excuses.