Sounds Like? An Audio Glossary Sidebars: 1-4
Although frequency-response anomalies (from flat) are readily measurable when they exist, other things which are not directly related to frequency response can affect apparent frequency response.
Harmonic distortion can sound like elevated treble response when, in fact, no such rise is measurable, and phase shift can cause an apparent thinning or dulling of the sound. Some subjective terms which are used to describe frequency response describe the sound's apparent response rather than its measured response.
Sidebar 2: About Height Information
Although our ears can locate the height of sound sources in front of us, stereo microphones and reproducing systems are not usually configured to handle height information. (Only a full Ambisonic system is inherently capable of it.)
Imaging of vertical information is unpredictable and anomalous, but all good stereo systems will produce enough vertical spread so as not to seem unnaturally flattened. Certain notes (and instruments) will often seem to detach from the generally horizontal soundstage, appearing to come from above or below the other instruments. Cymbals, for instance, are often heard as "arching over the orchestra."
Since vertical information is not (usually) recorded, the listener should try to ignore any apparent height cues. Tall tower-type loudspeakers, with their tweeters at the top and woofers at the bottom, often produce a vertically inflated soundstage and pronounced vertical wander which is hard to ignore.
Sidebar 3: Holt's Laws
1) The better the recording, the worse the performance, and vice versa.
2) The shriller the advertisement, the worse the product.
3) Every component is imperfect, and every imperfection is audible.
Sidebar 4: About Qualifiers
Because the process is so subjective, choosing the appropriate qualifier for an observation is one of the most slippery aspects of subjective reporting.
Whether an observation is judged to be "subtle" or "conspicuous" will depend on the reproducing system, the choice of program material, and the listener's mood, temperament, and acquired listening skills. What is "subtle" to one listener may be "moderate" to another.
A magazine reviewer unsure of his or her reputation for acuity will often inflate the audibility of something in order to demonstrate how extraordinarily perceptive he or she is. This misleads the reader.
The qualifier should be carefully chosen, and any misgivings about that choice should be explained, such as "Through my system, this was moderately audible." The system should, of course, have been previously described in the review, and perhaps characterized as "especially revealing" or otherwise.