Just intonation, or JI, differs from all other tuning systems, such as ET, well temperament and meantone, in that it is not fixed, and is entirely contextual in its application. It involves tuning intervals purely (perfectly) wherever one travels, such that no notes have fixed pitches, but their pitch is instead entirely dependent on the surrounding harmony, or ‘context’. For this reason, it is perhaps the most desirable tuning method that exists, only it requires excellent microtonal hearing, sound judgement and immense musicality on part of the performer, and is therefore the most difficult to achieve. In live performance, JI is something which is only possible on non-fixed-pitched instruments (that is, instruments that can alter their tuning incrementally during performance, such as strings and voice). The piano, guitar and harp are examples of fixed-pitched instruments and are thus incapable of just intonation.
Examples of JI issues.
1. Professional a capella (unaccompanied) choirs that routinely rehearse with a piano or keyboard instrument differ immensely in their tuning from true a capella choirs (with no fixed pitch instruments in rehearsal or performance). The first choir is forced to conform their tuning to the strictures of the piano and its tuning system (which will probably be ET). Thus, although the choir may be, from a technical perspective, perfectly capable of producing pure intervals, the great likelihood in performance is that they will not. The true a capella choir (assuming they have rehearsed together sufficiently) will, if they have good ears and sing intervals rather than pitches, produce (hopefully) pure intervals.
2. Violinists (and all string players for that matter) must alter their tuning depending on which instruments they are playing with. In a string quartet, for example, JI can and should be employed. However, when playing with a ET piano, they must in most cases play either in ET or close to it, as JI would make them fundamentally out of tune with their only accompanying instrument!
I said before that strings and voice are non-fixed pitch instruments. To be specific, strings are not fully free in their pitch modifications – they still have open strings which remain at a fixed pitch. Therefore, some compromises in the pursuit of JI need to be made.
3. If a piece for string orchestra is to begin in D major, work its way through a harmonic labyrinth and eventually find its way back to D, the final D will have to be identical to the initial one, as the open strings on all of violin, viola, cello and double bass would necessitate it. This is not so with voice, the truly free instrument with respect to pitch.
4. Some of the world’s best a capella choirs employ JI and can end up quarter tones sharp or flat of their starting point, due to the microtonal adjustments resulting from JI. Fundamentally, this is not a concern or a deficiency, unless the pitch is rising or dropping markedly due to bad vocal technique or poor listening by members of the ensemble.
Given the above information about the world’s most beautiful tuning method, and the limited contexts in which it is possible, it should not come as a surprise that the average joe may go an entire lifetime without ever hearing JI. What a shame!
Return to the Tuning and Temperaments homepage to find out about the historical temperament solutions that have been devised for fixed pitched instruments.