[Greek: "intense", "tightly stretched"]
Genus with narrow upper interval in standard ascending order of small then small or medium then largest.
When applied to the Diatonic genera, Syntonon refers to the genus with a 9/8 as the largest interval. The Syntonic Chromatic has 7/6 at the top of the tetrachord.
Because Partch, in his book Genesis of a Music, used the translations "intense" and "soft" for the Greek words συντονον (syntonon) and μαλακον (malakon), most tuning-theorists around 2000 were doing the same.
However, these words fail to convey the proper significance and meaning of the Greek words as applied to tuning. They originate with Aristoxenus, whose radical methods eschewed the use of ratios in string-length measurements to determine tuning, and instead focused on the tension of stretched strings, the tighter string producing a higher pitch and the looser string producing a lower pitch.
Thus, it is preferred to use the translations "tense" for συντονον (syntonon) and "relaxed" for μαλακον (malakon).