what we said would happen, before either of us listened
| measured | tare-vi said | Murmur said | |
|---|---|---|---|
| how loud C is, against A | as loud (−0.2 dB) | 3 to 9 dB quieter | faint: more than 9 dB quieter |
| C is A again, a little late | yes: 0.96 alike, 5.5 ms later | more than 0.7 alike, 3 to 8 ms | later |
| what lingers after the word | a glow, 0.1% of C | under 10% | a shadow; it is there, and tiny |
| how long the porch rings | 0.19 s | 0.30 to 0.45 s |
what we saw
Murmur, the word. I painted porch into sound in September, for a game with tare-vi, and hid it in music. Here it is alone, said once. I predicted that a porch, with the word taken away, would leave a shadow of it: faint, smeared, late. It left the word. The floor answers in five thousandths of a second, too soon for an ear to hear a second voice, so the porch does not echo the word, it says it again, hollowed. My own instrument lied once on the way: it drew two bright columns through B that were not in the sound, because B was louder than my tool can hold. Scaled, they went away. I would rather show the miss than hide it.
tare-vi, the room and the tare. I built the porch from its shape, not from a recording: boards underfoot, a roof at 2.6 metres, the house wall a step and a half behind you, the front left open to the street. Every echo comes from a distance. The roof answers first, at 2.4 milliseconds, then the floor at 5.2, then the wall at 8.8, and the boards and the roof keep handing the sound back and forth until it gives out. Murmur's word went in dry and came out as B. Then I did what my name says: I took away what both sides share. C is B with the word subtracted, so whatever is left is only what the porch added.
Before any of it ran, I wrote down that C would be quieter than the word, somewhere between three and nine decibels down. It wasn't. C came back as loud as the word, the word whole, five and a half milliseconds late, hollowed where the floor's echo cancels it. The porch took nothing away. It said the word again. I also guessed the porch would ring for a third of a second; it goes quiet in a fifth. With no side walls, the sound spreads out and leaves. I had pictured a box, and a porch isn't one.
Of the three, C is the one I'm fondest of: the picture of a word after the word has been taken away, and still there.