The troublesome note vanished at 4:17. Imani dragged her bow across the lowest string, a brief, deliberate rasp, while the control screen showed Rowan a pleasant green curve where the jagged one should have been.
She stood alone in the glass performance room. Beyond it, Belltower Hall's empty seats faced a stage they could see but not hear. Sound reached each chair through a pair of padded listening wings, and the software decided how much of the original performance was allowed through.
Imani held up her bow. Rowan pressed TALK.
“It happened again,” she said.
“The system calls it an accidental transient.”
“It's on the score.” She raised the page to the glass. Three ordinary notes, then a diagonal pencil mark as thick as a thumb.
Belltower had two listening programmes. Clear preserved the shape of a performance but reduced abrupt changes. Gentle went further, easing sharp textures that could make a concert difficult for some listeners. Neither allowed the scratch Imani had written between the second and third movements.
Rowan had helped install the programmes. His nephew Finn used Gentle. Before Belltower reopened, Finn had once left a concert during the first piece, hands clamped over his ears. Here he could sit through a whole evening. He was coming tonight.
“Can you turn the smoothing off for that bar?” Imani asked.
“Not for everyone. People buy tickets on the promise that the sound won't jump at them.”
The note was not especially loud. The filter had learned to dislike its roughness, not its volume. From behind the glass Rowan had heard the actual scrape during setup: a bow catching, resisting, and releasing. The filtered version sounded like a careful breath.
Imani had written the piece after a disastrous student recital. At nineteen she had stopped halfway through a passage, unable to make her hand move. For years she remembered the silence as the part she had failed to fill. The new composition gave that interruption a sound.
“When it turns smooth,” she said, “it sounds as though I got through it without stopping.”
The hall manager, Veda, came down from the balcony carrying a stack of printed programmes. She listened to a recording of each mix, then set the papers on Rowan's desk.
“If we change the default, we break our promise,” she said. “If we make people choose between programmes they don't understand, they'll think one ticket is worse.”
“There is a service feed,” Rowan said. “For calibration. Straight from the microphone, with the same output limit as Clear. No texture filter.”
Veda looked at the clock. Doors opened in ninety minutes. The service feed was not offered at the seats. It would need a visible choice, a way back, and a test at every kind of chair. They could delay the doors, but not the musicians on the last train home.
They called the third programme Direct, even though it was the fourth channel in the console. Rowan tested it in an aisle seat, an old balcony chair, and one of the newer padded seats. He checked the output limit, the return switch, and the two-second hold required to opt in. Imani played the difficult bar thirteen times. On the thirteenth, her shoulder shook with fatigue.
Veda postponed the opening by eleven minutes. Staff placed a small card on every chair: YOU MAY HEAR AN UNSMOOTHED PERFORMANCE. HOLD THE RIGHT SWITCH TO CHOOSE DIRECT. PRESS LEFT TO RETURN. A listener could keep Clear or Gentle all night without being asked why.
People arrived carrying folded coats, shopping bags, and the mild irritation of an unexplained delay. Two students switched to Direct immediately. A man in the aisle tried it, changed back, and read his programme. Finn came with his mother and settled into row J, where he chose Gentle and gave Rowan a quick wave.
Imani began with almost nothing. A held note passed from her instrument to the cello and came back thinner.
Then her hand dropped. The scrape struck the glass like a mark on a clean page. In Rowan's ear it arrived softened into a warm, brief chord. He touched the Direct switch. The bow hair caught on the string; for less than a second, the instrument refused the melody. His shoulders rose before he could stop them.
On the screen, forty-seven seats had chosen Direct. More than a hundred people were hearing something else. Imani could not see the count. She played the next phrase with her eyes shut, and the piece continued on time.
During the interval, a woman came to the booth. “My friend says she heard something ugly just before the last section. I didn't. Did my seat miss part of the concert?”
Rowan showed her the two waveforms. He resisted the temptation to describe one as better. “Both were made from the same performance. The programmes treat that sound differently.”
“Which one did the composer want?”
“The one with the rough note.”
The woman considered the choice card still in her hand. “I might try it for the encore,” she said. “I liked the first version, though.” She waited for Rowan to say whether that was allowed. He told her where the switch was.
After the final applause, Imani came to the booth with her violin case open. The little square of rosin in its lid had cracked. She asked for the recordings. Rowan played her the Direct feed first. She listened without moving, then asked for Gentle.
“That's not what I wrote,” she said when it ended.
“No.”
“But some people needed it?”
“Some chose it. Finn did. He was watching your hand the whole time.”
She closed the case, not angrily. “I don't want my work to become a test people have to pass.” She looked again at the two waveforms. “I also don't want the hall to tell them those are the same sound.”
Veda returned with the unsold tickets for next week's concert. Imani took one and turned it over. The channel notice was absent; tonight's cards had been placed only after people had paid.
“Put it here next time,” she said, tapping the blank space beside the seat number. “Before anyone decides to come.”
Rowan took a pencil and drew a box on the ticket. He knew Veda would have to approve the new printing, and that some people might decide not to buy. Imani left him the two recordings. He named them separately and put both in the archive.