Phrygian Gates is a broad monolithic arch roughly 24 minutes long which is built upon a plan that resembles the classic “tour” of the twelve keys. This particular voyage, however, takes a somewhat different route due to the exclusively modal nature of the writing. All the music is sounded in either the Lydian or the Phrygian mode, and the tonal scheme is such that each of the seven different pitches functions first as Lydian, then as Phrygian root. The sequence of roots travels by perfect 5ths half the distance of the full circle: A-E-B-F#-C#-Ab-Eb. Since each of these seven roots has both a Lydian and a Phrygian embodiment, there are a total of 14 sections with the modal oscillation among them providing the structural framework for the music.
The two modes, of course, have strongly opposed affects, and this duality or union of opposites is largely responsible for the music’s expressive content. The Lydian mode with its light, sensual, resonant personality is played off against the more volatile, unstable but often heroic qualities of the Phrygian.
Given the key scheme and the idea of alternating modes, the challenge in composing was to shape a meaningful arch out of the many smaller parts. Each of the 14 smaller sections would have its own special qualities: a different figuration, a new register, a quickening or relaxing of the pulse, a change of amplitude, etc. in some cases, as with Shaker Loops, one section would differ from its predecessor by the manner in which the performer physically produced the sound (cf. the Chopin Preludes). The “gates” of the title would be the moments of change, when some or even all of these elements were subject to transformation.
The obvious danger in an approach of this sort is that the result might strike the listener more as a patchwork construct than as a truly unified statement. Wanting to avoid this disparity, I worked on the piece always with the larger form in mind, one in which the really important change throughout the piece was indeed very gradual. In this sense the music falls into a simple four movement plan that has as its subject the life history of the softly repeated E’s which open the piece. As the music moves through the gates the quietly undulating quavers of the opening are gradually displaced by the stronger, more aggressive 16ths. The energy of these smaller values increases until, somewhere in the tenth minute, it peaks on a grand crescendo of rapidly resounding chords.
This climactic point is followed by a second part which, at a pulse one third faster, eases the high energy of the preceding passage down into the slow third part: a dark calm in C# Phrygian (subtitled “A System of Weights and Measures”) in which the pulsation of the earlier music is now transformed into a quiet, solemn tolling.
This slow tolling is ended abruptly by the appearance of the last section, itself an arc which ascends at high speed (mm.=180) from the rumbling lower depths of the piano up to the “soft peak” some five and half octaves above and then down again in a final “ride out” which, although rapidly alternating modes, maintains its uninterrupted forward motion to the end.
Phrygian Gates was commissioned by Mack McCray and generously funded by a group of members of the board of Trustees of the San Francisco Conservatory of Music (including the late Betty Dinner). It was first performed by McCray on March 17, 1978 at Hellman Hall in San Francisco.