Groven Piano Project
- the un-tempered clavier -
*** Hear recordings from the Premiere in Norway and
Gilmore Keyboard Festival ***
The following soundfiles provide a direct comparison between 12-tone equal temperament, (the standard tuning used with pianos today) and a variety of other tunings available on the Groven Piano. They are best heard using earphones or high-quality speakers. The first example is a D major chord played five times side-by-side. The first, third, and fifth times are tuned in just intonation, with acoustically pure thirds and fifths. The second and fourth times are in equal temperament. An organ timbre is used instead of piano to provide a longer sustained sound.
D Major chord Just - Equal - Just - Equal - Just
The next excerpt is a simple chord progression ( I - V7 - I ) played on the piano. The first and last times are in extended just intonation (with a 'blue' minor seventh), and the middle version is in equal temperament.
I - V7 - I progression Just - Equal - Just
Below are three versions of Edvard Grieg's piano arrangement of the folk tune Gjendines Bånlåt as performed live at the Groven Piano premiere in Oslo, Norway. It is a lullaby which Grieg learned from the folk singer Gjendine Slålien, heard in this archive recording. The piano version labeled 'Folk Music Scale' uses a fixed tuning with a noticeably lowered seventh scale degree similar to Slålien's tuning as it is still traditionally sung by folk singers. The final version utilizes the adaptive tuning feature of the Groven Piano, in which the tuning changes in real-time to optimally tune each chord in just intonation.
Edvard Grieg - Gjendines Bånlåt:
temperament - Folk
music scale - Adaptive just intonation
Next is the opening of the Prelude No.4 in C# minor from J.S. Bach's Well-tempered Clavier, Book II. You will hear a brief passage using adaptive just intonation, followed by a slightly longer version in equal temperament, and then again in just intonation.
J.S. Bach - Prelude in C# minor Just - Equal - Just
To demonstrate a somewhat different style, here is a Booogie-woogie piece by Ben Heneghan & Ian Lawson. The first soundfile contains excerpts in just intonation and equal temperament side-by-side. The entire piece can be heard in both tunings as well.
Harry's Boogie Just - Equal - Just -Equal - Just
Entire piece in Adpative just - Equal temperament
The adaptive tuning system used by the Groven Piano is also capable of handling more complex harmonies involving non-tertian chords and more remote key relations. This excerpt from Paul Hindemith's "Un Cygne" (from Six Chansons, 1939) includes a mixture of quartal and tertian chords. In comparison with the equal tempered version, the adapative tuning creates rich, colorful texture with both purer sounding consonances and more acute dissonances.
Paul Hindemith - Un Cygne
Equal temperament - Adaptive just
Many other instruments do not normally play in equal temperament and must make adjustments when playing together with piano. Here is late 19th-century composition for viola and piano by Alexander Glazunov in two tunings.
Alexander Glazunov - Elegie, Op. 44
Adaptive just -
Similarly, you can compare these two versions of George Gershwin's "It Ain't Necessarily So" from Porgy and Bess arranged for harmonica and piano.
George Gershwin - It Ain't Necessarily So
Equal temperament - Adaptive just
Frequently Asked Questions
Dr. David Loberg Code
Associate Professor of Music
School of Music
Western Michigan University
Kalamazoo, MI 49008