4 Duets for 2 Lutes: No. 2. —

Recording by Ingvar Karkoff.

Recording identifiers

ISRC
USB8U1038443
CopyrightID (CopyrightChains transaction hash)
0xafc01443fe502336f5c00e5be222f38aa1c860bca1af5af74bbfbb9f2d335cf7
Copyright registration time
2026-07-31T10:34:41+00:00

OpenTimestamps proof evidence

Bitcoin-attested timestamp
2026-07-31T12:24:41Z
Bitcoin block
960397
Canonical record hash
sha256:390430019999003a27545e3ca66a68df68db262b1bfdc6f7ade2ffaa72034c67

What this proof establishes

This recording belongs to ProofProfile's historical evidence base derived from the pre-2022 AcousticBrainz and MusicBrainz corpus. ISRC is the stable recording-level bridge from that source corpus to the authoritative cc-db-prod track record.

CopyrightChains and Bitcoin OpenTimestamps make the exact committed record independently verifiable today. The cryptographic proof does not by itself establish authorship or ownership of the underlying recording.

Read the complete pre-generative-AI provenance and verification method.