The Coull Quartet is an English string quartet that was founded at the Royal Academy of Music, London in 1974 under the guidance of renowned quartet leader, Sidney Griller. They were appointed Quartet
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x54559a46f38bdfb6c762a24360039f284f7b2df757618dc3786a23b29774a1e2. Chain 2 (Bitcoin): anchored in block 954667 (2026-06-21T07:29:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d008a209-cddc-4fe7-9ac1-58d0a6d488a4.json and https://artists.proofprofile.net/proofs/artist/d008a209-cddc-4fe7-9ac1-58d0a6d488a4.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Elgar: String Quartet – Bridge: Idylls – Walton: String Quartet
Songs from A E Housman's: A Shropshire Lad
Maw: String Quartet No. 3 - Britten: String Quartet No. 3