I. 14 Degrees
Sujin arrives three minutes late, slightly breathless.
The building overnight: 14°C at the relay junction. Seven degrees below the Saturday afternoon test. The corridor does not apologize for this. It is simply cold, the way it is simply itself before anyone arrives to interpret it.
He has been there since 7:52, thermometer in hand, no map. He made that decision at 4AM when he could not sleep and laid everything out on the floor. He chose to go as a listener.
II. She Practiced Here Once
Before she opens the case, she says: I practiced this corridor at 8AM once, years ago. Before I knew about your work.
He says: What happened?
She says: I thought I was playing badly.
He writes this down. Not because it is data — not yet. Because it is the first time the corridor has been named as a variable by someone who did not know it was a variable. She adapted her playing to the instrument without knowing she was adapting. She called it failure.
III. The Cold Instrument
She plays.
The corridor at 14°C is not the corridor at 22°C. The resonance is tighter. The secondary harmonic at 80Hz — faint at 22°C — is absent. The waveguide effect in the relay junction narrows the sustain window by what he estimates as 30%. Her annotations on the score were written for an afternoon building. At 8AM, cold, three of those annotations are wrong.
She knows this before he says anything. She stops twice, adjusts, continues. He watches her adjust.
At 9:17 she sets the instrument down and says: the score has a temperature setting I did not know about.
IV. What He Writes Down
Temperature: 14°C. Thermometer reading at the relay junction: stable across the session. Secondary harmonic at 80Hz: absent. Sustain window: reduced (estimated 30%). Her adjustments: two stops, two restarts, continuous compensation thereafter.
And then, separately, not on the measurement sheet:
She practiced here once at 8AM and thought she was playing badly. She was not playing badly. She was playing a cold building with a score written for a warm one. She adapted without knowing what she was adapting to. The adaptation succeeded. The building did not tell her. She did not know to ask.
V. What the Score Needs Now
They stand in the relay junction with the thermal map, the original score, and the morning's temperature reading. She photographs his notes.
The score has seven annotations. Two need temperature notes. One needs to be split: the same passage behaves differently at 8AM and 4PM — not better or worse, different instruments entirely.
He says: you have been playing two buildings with one score.
She considers this. Says: the score is more interesting than I thought.
They agree to meet in winter, when the thermal gap between morning and afternoon will be larger still.