Or, ‘Why your guitar doesn’t always sound like it’s in tune even though it is.’
This page gives an explanation of ‘tempered’ versus ‘just’ tuning. We’ll look at the flaws that are built into tempered tuning, and how it effects the guitar.
Equal Distance Every note on the guitar or piano is an equal distance from the next note. Each note represents a set musical distance. But it didn’t used to be that way. People used to divide the spaces within an octave a little differently than the way we do today.
Just-Tuning Early classical instruments were ‘just-tuned.’ This means that they were designed to play in tune in only a few keys. Believe it or not, D# and Eb used to be different notes, with different keys on the keyboard. Which note you used depended on the key you were in. No kidding.
You can find music that is recorded in just-tuning. The intervals sound different, better in some ways because close intervals play perfectly in tune.
Limitations Of Just-Tuning Just-tuned instruments have some serious limitations. They only sound good in certain keys, and you can’t play notes too far apart, or else octaves and higher intervals start to sound flat. To get around these restrictions, musicians developed tempered tuning.
All modern music is played in tempered tuning. Virtually all western music written since about 1700 has been in tempered tuning. Today, just-tuning is a curiosity for musicologists and students of period-music.
Alternate tunings are showing up in pop music, especially modern urban styles like hip-hop and rap. There are synthesizer add-ons that will detune certain scale notes by a quarter-tone. This makes your ‘regular’ major scale sound distinctly Arabic.
Problems With Tempered Tuning But tempered tuning has a built-in imprecision. It has several minor dissonances, and you become aware of this fact the first time you try to tune a guitar by ear. Part of the reason for this imprecision resides in the ear itself. I’ll explain that later.
Early Classical Music Music during the period before tempered tuning (before about 1650) almost never used notes outside of the key, but these notes were included as smaller, recessed keys. These are the black keys on modern keyboards.
All Possible Keys Tempered tuning revolutionized music during the period of J.S. Bach. Bach was one of the first to write music for a ‘well-tempered clavier.’ Now it was possible to play chords and scales in any of 12 keys. Today, the key of ‘Gb’ plays in tune just as well as in ‘C’ or any other key. For the first time, it was possible to change keys in the middle of a piece, and to expand harmony to include all of the notes that were excluded before. This is when European keyboard and orchestral music first began to use many of the musical forms we recognize today.
Sometimes when you’re recording a guitar part where a 3rd or a 6th is prominent, it’s good to just-tune that interval to decrease the enharmonicity. This usually means lowering the 3rd or 6th relative to the tonic (‘one-note’).
Built-In Dissonance Tempered tuning contains built-in dissonance, also known as ‘enharmonicity.’ This is the reason you can’t tune with third or sixth invervals. Thirds and sixths which sounded so pure in just-tuning were ‘sacrificed’ so that octaves, fourths and fifths are always in tune in any of the 12 possible keys, and in all octaves simultaneously.
Tune With Consonant Intervals ‘Consonant’ intervals are unisons, 4ths, 5ths and octaves. Tuning with these intervals is the only way to tune a guitar by ear.
An Evolving Concept Tempered tuning isn’t an exact science. There is disagreement to this day between piano tuners as to the exact number of cents given to each pitch to create the best sound overall. It’s one of those topics for debate with musicologist, like whether we should all use A440 or C256. (We are A440.) In other words, it doesn’t matter much to everyday people like us. But it’s kind of interesting. A tuned piano today may sound slightly different than a tuned piano 100 years from now. But $5 says you wont be able to tell the difference. Call me in a hundred years …
The Well-Tempered Guitar
Copyright 2001 by Greg Varhaug. All Rights Reserved.