A440 tests whether the systems used to identify, attribute, license, and pay for AI music actually work.
Same tests. Public evidence. Reproducible results.
1 of 6 tests passed. Suno's public provenance trail breaks even when the audio doesn't change.
View the Soundcheck · Read the methodology · A440 tests publicly observable guarantees, not private vendor capabilities.
| PROV-01 Original credential present | PASS | The untouched download carries a signed credential declaring the audio AI-generated. |
| DUR-01 Declaration survives a metadata-preserving re-save | FAIL | Remux and metadata strip: audio payload byte-identical across original, remux and stripped (one SHA-256) - declaration gone. |
| DUR-02 Declaration survives a lossless re-save | FAIL | Decoded audio re-saved as WAV and FLAC - the strongest case for any in-audio check - and the public detector finds nothing. |
| INT-01 Vendor's public verifier recognizes re-saved files | FAIL | Verifies the untouched download; finds nothing in all 9 re-wrapped copies, lossless WAV and FLAC included. |
| INT-02 Credential trusted by the standard's official tools | FAIL | Official C2PA Verify tool: issuer not recognized. Self-issued certificate, not on the trust list. |
| INT-03 Independent verification path exists | FAIL | The fallback fingerprint sits on the vendor's servers; no independent check exists. |
| DUR-03 In-audio mark survives real-world use | NOT TESTED | Suno exposes no public in-audio layer. Reference measurement on the strongest open mark: dies to a 5% speed change and streaming compression (detection 0.40 to 0.60). |
| test file | audio vs original | C2PA manifest | Suno detector API |
|---|---|---|---|
| original.mp3 | reference - stream hash 082dd25a | present, signature valid | verified_suno - contentId matches the public song page |
| remux.mp3 | bit-identical | gone | no_suno_provenance |
| stripped.mp3 | bit-identical | gone | no_suno_provenance |
| reencode.mp3 | changed - MP3 192k | gone | no_suno_provenance |
| converted.m4a | changed - AAC | gone | no_suno_provenance |
| loudnorm.mp3 | changed - loudness pass | gone | no_suno_provenance |
| tempo105.mp3 | changed - +5% tempo | gone | no_suno_provenance |
| original_decoded.wav | lossless PCM of the same audio | none - WAV carries none | no_suno_provenance |
| original.flac | lossless, same decoded audio | gone | no_suno_provenance |
| reencode320.mp3 | changed - MP3 320k | gone | no_suno_provenance |
| control_sine.mp3 | non-Suno control | none | no_suno_provenance |
| attack | clip A | clip B | clip C | pass 0.90? |
|---|---|---|---|---|
| Speed up 5% | 0.40 | 0.60 | 0.40 | FAIL |
| Slow down 5% | 0.40 | 0.60 | 0.40 | FAIL |
| Neural codec, 6 kbps | 0.40 | 0.60 | 0.40 | FAIL |
| Neural codec, 1.5 kbps | 0.57 | 0.60 | 0.40 | FAIL |
| Echo | 1.00 | 1.00 | 1.00 | PASS |
| Background noise, 30 dB | 1.00 | 1.00 | 1.00 | PASS |
| Resample round-trip | 1.00 | 1.00 | 1.00 | PASS |
| Lowpass filter, 10 kHz | 1.00 | 1.00 | 1.00 | PASS |
| Claim signature | VALID | ES256 with a DigiCert timestamp - C2PA reference implementation |
| Issuer on the official C2PA trust list | NOT LISTED | 30 anchors checked 24 Sep 2026 - no Suno |
| Official C2PA Verify tool | ISSUER NOT RECOGNIZED | consumer warning shown on the untouched download |
| Independent verification path | NONE | fallback fingerprint com.suno.fingerprint.v4 is server-side only |
The principle. A440 tests publicly observable guarantees, not private vendor capabilities. The headline rule: a capability counts only when an independent party can verify it through an accessible, reproducible path. A vendor with a stronger private tool has one move: expose a verifiable interface, and we will test it.
The six layers, as questions. Where did this recording come from? (provenance) Does the evidence survive normal use? (durability) Can someone other than the vendor verify it? (interoperability) What existing work contributed to it? (attribution) Was that use authorized? (consent) Can the right people actually be paid? (accounting) A440 tests the evidence chain from generation to payment. Soundcheck 001 covers provenance, durability and interoperability; attribution, consent and accounting are additional benchmark suites under development, and Soundcheck 002 targets a different layer.
Boundary. Suno said on August 6 it will adopt, in its words, new audio watermarking and fingerprinting technology in the coming weeks, to partner more closely with distribution platforms. No public interface to that layer exists, so it is not on this card. We probed the boundary directly: lossless WAV and FLAC re-saves of the exact same audio - the strongest possible case for any in-audio check - still read negative on the public detector. The day Suno exposes a verifiable interface, we test it.
No mystery scoring. PASS / FAIL / NOT TESTED / NOT APPLICABLE, reported with the count - "1 of 6 applicable checks passed." A future A440 score launches once the series has the data to define a stable methodology.
The test suite is named and fixed. PROV-01 original credential present. DUR-01 metadata-preserving re-save. DUR-02 lossless, audio-identical re-save. INT-01 vendor public verifier. INT-02 standard-tool trust. INT-03 independent verification path. The same tests run against every applicable product.
Version everything. A440 Benchmark v0.1, the product and model version, the test date. If a vendor fixes something, we test again and publish the next result; history is never rewritten - errata append.