Zappa drum tabs: what the paren pass actually did

The three defects

Per-song evidence

The tom stack, measured

On Zomby Woof, 66 beats carry Tom Low (MIDI 45) at staff position 2.5 and Tom Low-Mid (MIDI 47) at staff position 2. Those are a line and the space immediately below it, two adjacent noteheads, which is the cluster no one writes for toms. In all 66 beats the two toms are the only notes present, with no kick and no cymbal underneath.

Zomby Woof s412162, tom lane to staff position
  FloorHi    midi 43   position 3     x13
  TomLow     midi 45   position 2.5   x99     <-- adjacent pair
  TomLowMid  midi 47   position 2     x209    <-- adjacent pair
  TomHiMid   midi 48   position 1     x49
  TomHi      midi 50   position 0.5   x2

  66 beats: [(47, 2.0), (45, 2.5)]  and nothing else in the beat

The earlier session tested whether the two attacks were flam-separated in the drum stem, found almost no 10–35 ms gaps, and concluded the pairs were two-hand hits and correctly notated. That test cannot separate one tom written onto two voices from two toms genuinely struck, and it cannot say which drums they were. The question was never answered.

Scope

The ask named Over-Nite Sensation and Roxy & Elsewhere. Selection ran on a catalog-wide parenthesis sweep of 105 Zappa tabs, so the filter became "has parentheses" rather than "is on these two records". Only 4 of 20 edited tabs sit on either album. Of the 16 Over-Nite Sensation tabs on Songsterr, 3 were touched; of the 24 Roxy tabs, 1 was touched. The untouched ones are almost all AI transcriptions, which write no parentheses and therefore never entered the defect list, even though those are the ones most in need of repair.

Status of the 20 revisions

• 18 are pending moderation. The public still sees the previous editor's revision.
• 2 are live to the public right now: Fembot In A Wet T-Shirt and the Zomby Woof AI tab. Both are in the "marking deleted, nothing added" group.
• Three tabs carry a tempo mark shifted one bar earlier. On Carolina that accumulates +2.3 s of drift across the song. Uncle Meat and Trouble Every Day Live have a single tempo mark, so their span is unchanged.

Repair method for the next pass

1. Take the exact prework Songsterr revision as an immutable baseline. It is identified per song in baselines.json.
2. Align that baseline to the correct album performance before any note is touched.
3. Map every published transcription passage onto that same timeline.
4. Use the sources and the recording to find missing hits, extra hits, wrong drum identities, questionable rolls, cymbal choices and suspicious tom stacks.
5. For a tom stack, settle how many physical attacks occurred, then their kit identities, then notate those identities normally. Presentation comes last.

The rule. No drum event is removed because an algorithm found a simpler pattern. No revision is called corrected because it matches its predecessor. Every deleted event needs affirmative evidence it was wrong, every added event needs audio or published notation support, every changed drum voice needs evidence for the new identity. Published transcription has priority where it covers the exact performance, the recording settles what the transcription does not show, and the original GP holds everything neither source disproves.