The terms TUNING, TEMPERAMENT, PITCH, and FREQUENCY BASIS are used quite commonly on forums and in marketing data put out by harmonica companies. The standard diatonic harmonica has a series of notes that are commonly referred to as RICHTER TUNING. Although the name is not technically correct, common usage has taken over and it has become synonymous with the tuning layout that comes on almost all stock production harmonicas. When we refer to ALTERNATE TUNING, we are referring to deviations in this layout where specific reeds are tuned to a completely different PITCH or note. Examples of different tunings are Paddy Richter, Country Tuning, and Melody Maker Tuning. In each of these cases, specific notes are changed to a completely different pitch. PITCH refers to the specific note that a reed is tuned to (ie A, Bb, C, etc).
Temperament refers to the way a harmonica is tuned to itself. In other words, temperament refers to how each note is tuned relative to other notes on the harmonica. The tuning of harmonicas and other instruments is part science and part art. In many cases, mathematical perfection is not necessarily desired. Notes that are played simultaneously do not always sound as pleasant when each note is tuned perfectly. Hence, harmonica companies frequently tune some notes sharp and some notes flat so that chords have a more desirable sound. Most players do not notice these deviations but as players progress and play more complex styles of music, the playing of chords becomes less important giving way to perfect pitch. When harmonicas are tuned to the exact mathematically calculated pitch on every reed, we call that Equal Temperament. Lee Oskar harmonicas and Golden Melodies are tuned to ET from the factory. Almost all other harmonicas are tuned to what is called COMPROMISE TUNING. There is no exact formula for CT but rather slight differences based on several factors. It is generally assumed that most players perform in 2nd position and hence, CT places the deviations in pitch (Usually just a few cent) in places that will allow the draw and blow 1-4 hole chords to sound good while at the same time keeping the notes consistent across the harp so the tongue blocked octaves are in unison.
FREQUENCY BASIS refers to the baseline frequency a harmonica is tuned to. This is most commonly set at A=442. Although many instruments are actually tuned to A=440, harmonica companies tune slightly sharp to allow for certain factors that cause a harmonica to go slightly flat. Recording industry personnel frequently expect session players to play instruments tuned to 441 or 440 as sometimes free reed instruments can sound shrill. This is generally not noticed in a live setting unless the player is performing strictly acoustic and with a lot of string instruments.
This discussion is not scientific and volumes have been written about each topic. It does provide a basis of understanding so that a player can communicate effectively with harmonica technicians and other players.
My specialty at 16:23 Custom Harmonicas is providing technical assistance to players and recording musicians who need special temperaments, temperaments, and frequency basis tunings on their harmonicas.
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