sympathetic-strings carries DC, and its ring test passes on the offset #101

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opened 2026-09-24 12:49:58 +00:00 by bcox · 0 comments

bcox commented

2026-09-24 12:49:58 +00:00

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The burst pluck carries DC, an open-open line recirculates it at its loss gain, and a string driven from that output through kInput integrates it with a gain of hundreds. Measured on sympathetic-strings (C-E-G held 1 s, 2 to 4 s): the taraf's raw RMS is -30.3 dBFS and its mean-removed RMS -88.7, so Bank.TheSympatheticStringsRingAfterThePlayedStringIsDamped's taraf > -60 passes on the offset, not on the ring.

The passive-bridge branch adds WaveguidePatch::dc_block (format 1.11, a one-pole at the layer's output, corner f0/8, off by default) and the damper-pedal patch turns it on; sympathetic-strings was left unchanged on purpose, since turning it on changes a shipped sound. Two things to decide: whether the patch takes the block, and, either way, the ring test should read the mean-removed level so it measures what it names.

See docs/superpowers/ledgers/2026-09-23-passive-bridge-ledger.md, "The damper pedal" and Follow-ups.

The burst pluck carries DC, an open-open line recirculates it at its loss gain, and a string driven from that output through `kInput` integrates it with a gain of hundreds. Measured on `sympathetic-strings` (C-E-G held 1 s, 2 to 4 s): the taraf's raw RMS is -30.3 dBFS and its mean-removed RMS -88.7, so `Bank.TheSympatheticStringsRingAfterThePlayedStringIsDamped`'s `taraf > -60` passes on the offset, not on the ring. The passive-bridge branch adds `WaveguidePatch::dc_block` (format 1.11, a one-pole at the layer's output, corner f0/8, off by default) and the `damper-pedal` patch turns it on; `sympathetic-strings` was left unchanged on purpose, since turning it on changes a shipped sound. Two things to decide: whether the patch takes the block, and, either way, the ring test should read the mean-removed level so it measures what it names. See `docs/superpowers/ledgers/2026-09-23-passive-bridge-ledger.md`, "The damper pedal" and Follow-ups.