Final answer:
The concept of Sound Symbols Association is not explicitly defined by the options in the question, as they relate to various elements of music such as timbre and pitch. Timbre refers to the quality that allows instruments to be distinguished by sound even when the same note is played, while loudness perceives the intensity of sound, and pitch is the perception of sound frequency.
Step-by-step explanation:
Sound Symbols Association refers to the concept of understanding and identifying properties of sound and how they are represented symbolically, particularly in the context of music education. The original question pertains to which aspects of sound are taught to mastery in two directions, and the options given are related to various elements of sound in music. However, let's clarify some misconceptions presented in the question: pitch and rhythm, timbre and volume, harmony and melody, and dynamics and tempo are all critical components of music, but they are not the aspects specifically referred to as 'Sound Symbols Association'. Instead, Sound Symbols Association generally involves the relationship between the auditory qualities of sound, such as pitch and timbre, and the symbols used to represent them, such as musical notes and notation.
The perception of sound involves several properties. Timbre is the characteristic that allows us to distinguish different sounds when the same note is played on different instruments, as in the example of a violin and a piano playing middle C. Timbre is associated with the complex interplay of frequency, amplitude, and timing of sound waves and is a more subjective aspect of sound perception, often described with words such as dull, brilliant, warm, cold, pure, and rich. Meanwhile, the perception of intensity is known as loudness, which is influenced by intensity but also by frequency, as the ear's sensitivity varies across the frequency spectrum.
Furthermore, the perception of frequency is termed pitch. People generally have excellent relative pitch and can differentiate between frequencies that differ by 0.3% or more. This ability is directly related to the frequency of the sound waves and underlies our capacity to recognize musical notes and their combinations as music. Some individuals possess perfect pitch, enabling them to identify musical notes without any reference tones.