thumb|right|Julius Patzak Julius Patzak (9 April 189826 January 1974) was an Austrian tenor distinguished in operatic and concert work. He was particularly noted in Mozart, Beethoven and in early 20t
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 0x7625bf4b07c35ab4a8a9c60f72ed4f7a7d65692b5262d308c66229dc2e70be1c. Chain 2 (Bitcoin): anchored in block 954065 (2026-06-17T08:10:43Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/456ab2ab-83eb-4b1b-ba36-c406f67e8969.json and https://artists.proofprofile.net/proofs/artist/456ab2ab-83eb-4b1b-ba36-c406f67e8969.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Beethoven: Symphony No. 9 in D Minor, Op. 125 "Choral"
Salome op. 52 starring Maria Cebotari live her only complete Recording
Mahler: Das Lied von der Erde & Rückert Lieder
Mahler: Das klagende Lied - Schubert: Die schöne Müllerin, Op. 25, D. 795
LP Pure, Vol. 28: Bruno Walter Conducts Mahler (Recorded 1952)
Mahler: Das Lied Von Der Erde (The Song of the Earth)
Waltershausen: Oberst Chabert (Recorded 1956)
Mozart: Don Giovanni, K. 527 (Sung in German) [Recorded 1936]
Mahler: Das Lied von der Erde, Three Rückert-Lieder Songs [1952]
Lebendige Vergangenheit - Julius Patzak (Vol.2)
Reisebuch aus den österreichischen Alpen
Beethoven: Missa solemnis in D Major, Op. 123 (Live)
Lieder von Franz Schubert und Richard Strauss
Julius Patzak - The Early Operatic Recordings
Mahler: Kindertotenlieder / Brahms: Liebeslieder-Walzer
Mozart: Sérénade No. 7, K. 250 "Haffner" (Mono Version)
Mozart, Süssmayr: Requiem (Mono Version)
Mahler: Das Lied von der Erde; 3 Rückert Lieder
Das Lied von der Erde: 1. Das Trinklied vom Jammer der Erde
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd80804f6adaf4f8b9585e72f189fb85bc61cdf32a5a17d38e71cc61ea991018d. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBF075200011.
Das Lied von der Erde: 2. Der Einsame im Herbst
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd2c0891341ca1be400e113f2b7152049fd82013265d0f2ef8900a1a4e721539e. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBF075200012.
Das Lied von der Erde: 3. Von der Jugend
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x83804876a552bad04eb4a0d828654fa8c7aa448712e924dd690bc0d6a49ab195. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBF075200013.
Rückert-Lieder: Ich bin der Welt abhanden gekommen
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x551df6b381c153bd19c672a298a0e25ffdf9b62a3d65ffa3ff2fa799104d172e. Chain 2 (Bitcoin): anchored in block 957075 (2026-07-07T18:50:38Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBF075210051.
Rückert-Lieder: Ich atmet' einen linden Duft
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9289970ecd8718ebb8e144ccb3c74346501c748ecc565ef5dc8cc365f86c5ee5. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBF075210052.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb6d6dd79f77aa13597580375b2de94c7290c32ddd8f7ccd562e46f63e6e27731. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBF075210053.
Das Lied von der Erde: 5. Der Trunkene im Frühling
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5c9d93e781a6e7ada143f5cf61cd1201cf7256bbbe3d5d80c9f4afff900131ce. Chain 2 (Bitcoin): anchored in block 960455 (2026-07-31T19:53:13Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBF075200015.
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
J. Strauss II: Die Fledermaus (Mono Version)
Haydn: La Création, extraits (Mono Version)
Nicolai: Horch, die Lerche singt im Hain
Mozart: Don Giovanni, K. 527, Folget der Heißgeliebten (Sung in German)
Brahms: Liebeslieder-Walzer; Neue Liebeslieder-Walzer