Concert A

As explained in Learn Haskell by Example

Concert A is the musical reference pitch conventionally assigned a frequency of 440 Hz.

Concert A is the reference pitch assigned to 440 Hz. Measuring semitone distances from it provides a convenient basis for calculating other frequencies in 12-tone equal temperament. section 10.4.1

Frequency checks

Treating concert A as semitone distance 0 gives 440 Hz; moving 12 semitones upward gives 880 Hz, while moving 12 downward gives 220 Hz. The chromatic note A4 therefore maps to 440 Hz. section 10.4.1

Figure 10.8 Formula to compute the frequency (f) from a given semitone distance to concert A (s) in 12-tone equal temperament

Use the frequency formula to convert a semitone distance from concert A into a pitch frequency. section 10.4.1

How Learn Haskell by Example covers it

How deep it goes

Defines the 440 Hz convention and applies it through a frequency formula, without developing tuning theory beyond 12-tone equal temperament.

Examples

Uses A4, semitone offsets, octave checks, chromatic note conversions, and a generated melody.

What you can do after

Evaluate pitch frequencies from semitone distances or chromatic note names using concert A as the reference.

How it connects

Connects frequency with semitones, musical notes, chromatic notes, pitch, and octave relationships.

liveBookmanning.com

Read Learn Haskell by Example on liveBook Get the book at manning.com

This explainer was generated by Manning's knowledge graph from the text of Learn Haskell by Example. The section links point to the parts of the book it draws on.