Key vs. Tonality

Attribute	Key	Tonality
Definition	A specific set of pitches that form the basis of a piece of music	The overall sound or feel of a piece of music based on the relationships between notes
Major/Minor	Can be major or minor	Can be major or minor
Scale	Based on a specific scale	Based on a specific scale
Key signature	Indicated by key signature	Indicated by key signature
Modulation	Can modulate to different keys	Can modulate to different tonalities

Definition

Key and tonality are two fundamental concepts in music theory that are often used interchangeably, but they have distinct attributes. Key refers to the central note or chord around which a piece of music revolves, providing a sense of stability and resolution. Tonality, on the other hand, refers to the overall system of relationships between notes in a piece of music, including the key but also encompassing other harmonic and melodic elements.

Function

Key serves as a reference point for the listener, helping to establish a sense of tonal center and providing a framework for understanding the harmonic and melodic content of a piece. Tonality, on the other hand, is a broader concept that encompasses the relationships between different notes and chords within a piece, creating a sense of tension and release that shapes the overall emotional impact of the music.

Characteristics

Key is typically defined by the specific notes and chords that are used in a piece of music, with the tonic chord serving as the primary point of resolution. Tonality, on the other hand, is more fluid and can be established through a variety of harmonic and melodic devices, including modulation, chromaticism, and non-diatonic chords.

Development

The concept of key has been a central element of Western music theory for centuries, with composers such as Bach and Mozart using key signatures to organize their compositions and create a sense of unity and coherence. Tonality, on the other hand, has evolved over time to encompass a wider range of harmonic and melodic possibilities, allowing composers to experiment with new sounds and textures.

Analysis

Key analysis focuses on identifying the central key of a piece of music and understanding how it influences the overall structure and emotional impact of the music. Tonality analysis, on the other hand, involves examining the relationships between different notes and chords within a piece, as well as the ways in which these relationships create tension and resolution.

Impact

Key and tonality both play a crucial role in shaping the listener's experience of a piece of music, providing a sense of structure and coherence while also creating emotional depth and complexity. By understanding the differences between key and tonality, musicians and listeners can gain a deeper appreciation for the rich tapestry of sounds and textures that make up the world of music.