v2.0.0 — measured 65.875 kbps acoustic goodput

v2.0.0 — measured 65.875 kbps acoustic goodput

Cyrinx 2.0 substantially raises measured MacBook Pro-to-Pixel 7a near-field
goodput while retaining explicit accounting and resilience boundaries.

Measured results

• The schedule-comparable flagship measured 65.875 kbps mean strict ordered
  byte-verified goodput, recovering 4,215/4,280 blocks (98.481%). It is 1.801x
  the accepted 36.571 kbps benchmark and 49.0% above its prospective paired
  44.199 kbps control.
• The candidate won all eight order-balanced pairs (p = 1/256) but failed its
  predeclared baseline-equivalent reliability gate: the paired control
  recovered 2,999/3,000 blocks (99.967%).
• A separately classified zero-gap profile measured 69.652 kbps and recovered
  6,129/6,760 blocks (90.666%). It is not schedule-equivalent to the flagship
  and also failed its reliability gate.
• Replaying identical flagship captures through frozen receivers isolated a
  +347-block gain from frequency-local known-pilot reliability: 4,215 versus
  3,868 recovered blocks, with all eight runs improving.

Engineering changes

• Canonical portable-C 64-QAM rate-2/3 profiles with CP96 and route-qualified
  pilot schedules.
• Frequency-local known-pilot LLR reliability with deterministic edge and
  nonfinite-input behavior.
• Payload-independent held-out-pilot selection between the primary microphone
  and two-microphone maximal-ratio combining.
• Fixed receiver-contract validation and thin Swift bindings for the new
  profiles and diversity diagnostics.
• Evidence-bound campaign accounting, provenance, retained-failure semantics,
  and paired statistical gates.
• A separate 11-page Cyrinx 2.0 follow-on paper documenting improvements,
  rationale, rejected branches, limitations, and future 3 ft work.

Scope and limitations

These are host-decoded measurements for one near-field route, one MacBook Pro,
one Pixel 7a, and one pose. The flagship improves throughput but does not match
the conservative control's block recovery. Android JNI/live decoding, a
reliability-qualified 3 ft profile, an integrated ultrasonic mode, and a
pleasant-audible mode remain future work.

Tracked ledgers and content hashes are included in the source archives. Full
raw captures, execution manifests, frozen binaries, and detailed replay reports
remain local ignored artifacts and are not part of this release.

Release artifacts

• cyrinx-2-goodput.pdf — focused Cyrinx 2.0 follow-on paper
• cyrinx-acoustic-link.pdf — revised Cyrinx 1.0 system paper and historical
  measurement record