Stop treating the Second Tone like a theological mystery. One of the most annoying hurdles for Byzantine Polyphony composers and arrangers is the Second Tone’s tendency to snap between the chromatic Byzantine Mode and the Diatonic Mixolydian. This phenomenon is most common in the double Katavasiae when both are in the Second Tone (e.g., on Epiphany), where the plain hymn is chromatic and the Iambic hymn is diatonic.
Traditionalists call this allilodaneismos (“interborrowing”) and will lecture you about the “attraction of the voices” until you fall asleep. Ignore them. For the modern polyphonist, this is simply a Common-Tone Modulation. Here is how you execute it without losing your mind.
The Mechanics: The “D” Pivot
Second Tone is the environment. Inside that framework, it swaps modes.
- State A (Chromatic): You are in D Byzantine Mode.
- Notes: D, E♭, F♯, G, A, B♭, C♯, D
- Tonic: D
- State B (Diatonic): You are in F Mixolydian.
- Notes: F, G, A, B♭, C, D, E♭, F.
- Tonic: F. This is the anomaly. Naturally, we’d expect G Mixolydian.
The connection here is the note D, and it’s not very obvious.
In the Chromatic mode, D is your Root (1st).
In the Diatonic mode, D becomes the Submediant (6th).
The modulation relies entirely on recontextualizing the note D. Instead of traveling to a new key, you are standing on the same note and changing the floorboards underneath it. This may surprise those who’d expect G to be the tonal center. Nope, it’s D.
How to Compose the Switch
When the Byzantine hymn ends, the next hymn will be in the Mixolydian mode positioned one whole step lower than the relative Mixolydian of the previous hymn.
The “Phrygian Signature” Mnemonic:
To find the correct key for the Diatonic section, take the Root of your previous Byzantine piece and apply a Phrygian Key Signature. Then, write your Mixolydian piece using that signature.
Example 1 (D Root):
- Previous Piece: D Byzantine.
- Use the key signature of D Phrygian (2 flats: B♭, E♭). That signature produces F Mixolydian.
Example 2 (F Root):
- Previous Piece: F Byzantine (using G♭, B♭, D♭).
- Use the key signature of F Phrygian (5 flats: B♭, E♭, A♭, D♭, G♭). That signature produces A♭ Mixolydian.
If modulating within the same hymn:
Modulating within the same hymn (or after a sticheron verse) is also common. Assuming D Byzantine:
- Establish the Chromatic: Your melody and harmony are circling D with those heavy F-sharps and E-flats.
- Hold the D: The melody hits a unison D.
- Drop the Floor: While holding that D, shift the harmony from D Major (or D5) to B♭ Major or F Major. Why? Because D is the 3rd of B♭ and the 6th of F.
- The New Reality: You are now in F Mixolydian. The F♯ sinks to F-natural; the C♯ sinks to C-natural. The melody feels brighter, less tense.
How to Get Back
This is where most arrangements fail. You are in F Mixolydian, but you need to return to the D Chromatic scale for the next verse. If you resolve strongly to F Major (the tonic of the diatonic section), the return to D Byzantine will sound jarring and amateur, like a bad DJ crossfade.
The Trick:
You must treat the Diatonic section as if it is in a permanent state of Deceptive Cadence. In Modal Harmony terms, write a Phrygian cadence but avoid using C at all; instead use only one A (open 5th) or only one G (preparation) in the inner voices.
- Write your F Mixolydian lines.
- Do not cadence on F.
- Force the melody to end the phrase on D.
- Harmonize this final D as a unison, an open fifth (D-A), or an open fourth (D-G) to taste.
By ending the diatonic section on its 6th degree (D), you have essentially created a Phrygian-style half-cadence. The ear is left hanging on D. This allows you to immediately re-introduce the E♭ and F♯ of the Byzantine scale for the next verse without anyone blinking.
Summary for the Composer
- Going Out: Pivot on D. It transforms from root to 6th.
- Coming Back: Land on D. It transforms from 6th back to Root.
Practicality is the name of the game here. The finalis of one piece just becomes the root for the next through a modulation. And thus, we don’t need to use fancy terminology and mystical theory rules.