The Sofia Philharmonic (Bulgarian: Софийска филхармония) was founded in 1893. The current music director is Nayden Todorov. The Sofia Philharmonic includes the National Philharmonic Orchestra, Natio
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 0x91a2d9c22365fef48dae0251b4278057105ad8a59089a0a3c774785bc8a74384. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/205ec81c-340a-4a0d-8c7d-660373901e4f.json and https://artists.proofprofile.net/proofs/artist/205ec81c-340a-4a0d-8c7d-660373901e4f.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Emil Tabakov: Complete Symphonies, Vol. 7 (Live)
Tchaikovsky: Complete Works for Violin and Orchestra
Classical Chamber Music: Mozart Piano Sonatas
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 0xf63d95f961bf9f829159aacae861103f24ab6175ecf8ff1feb93915e07714c1d. 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/DEAD61605001.
La traviata, Act I: Libiamo ne lieti calici
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La traviata, Act I: Dell'invito trascorsa è già l'ora
Svetoslav Obretenov National Philharmonic Choir
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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
La traviata, Act I: Follie! Delirio vano è questo! - Sempre libera
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Turandot & Madamn Butterfly - Opera Highlights
Teresa Procaccini: Musica per orchestra IV
Peter Hristoskov - Violinist and Composer, Pt. 2
Dukas: L'Apprenti Sorcier, Saint-Saens: Danse Macabre, Le Carnaval des Animeaux & Ravel: Ma Mere L'Oye
Brahms: Tragic Overture - Symphony No. 4
Brahms: Symphony No. 3 - Haydn Variations
Brahms: Academic Festival Overture - Symphony No. 1
Stravinsky: Pulcinella Suite - Jeu de Cartes - Symphony for Wind Instruments
Piano Concerto, No. 3 in C Minor, Op. 37 (Remastered 2024)
Ernst Toch: Zweites Klavierkonzert, Op. 61 & Musik für Orchester und eine Baritonstimme
Piano Works: Beethoven, Chopin and Debussy
Rabaud: Symphony No. 2 - La procession nocturne - Eglogue
Antonín Dvořák: Symphony No. 9 in E Minor, "From the New World", Op. 95, B. 178
Sergei Rachmaninoff: Symphony No. 2 in E Minor, Op. 27
Beethoven: Concert for Piano and Orchestra No. 3 in C Minor, Op. 37
Beethoven: Concert for Piano and Orchestra No. 5 in E-Flat Major, Op. 73
Johann Sebastian Bach - Antonio Vivaldi - Wolfgang Amadeus Mozart: Concerts for Violin and Orchestra
Gustav Mahler: Symphony No 8 in Es-Major, "Symphonie der Tausend"
Gustav Mahler: Symphony No 7 in E moll, "Lied der Nacht"
Gustav Mahler: Symphony No 6 in A moll, "Tragische"
Gustav Mahler: Symphony No 5 in Cis moll
Franz Joseph Haydn: Concerts for Piano and Orchestra
Bulgarian National Svetoslav Obretenov Choir
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La Traviata, Act I: Brindisi - "Libiamo ne' lieti calici" (Instrumental Version)
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Fidelio, Op. 72: Act I: Finale: O welche Lust, in freier Luft den Atem leicht zu heben!, "Prison Chorus"
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Klavierkonzert Nr. 5 Es-Dur, Op. 73: I. Allegro
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La Traviata, Act I: Brindisi (Instrumental Version)
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Tosca, Act II: Vissi d'arte (Instrumental Version)
Classical Music for Learning: Great Masterpieces to Improve Studying and Mental Focus
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Tosca, Act III: "E lucevan le stelle" (Instrumental Version)
Classical Stress Relief: 99 Must-Have Classical Meditation & Relaxation
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Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8f523e1da93771a7a07b6cce0be5bce0d28d37bdb079e3b3634e79cb7037b2f1. 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/US5541301582.
Klavierkonzert Nr. 5 Es-Dur, Op. 73: II. Adagio un poco mosso
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Klavierkonzert Nr. 5 Es-Dur, Op. 73: III. Rondo: Allegro
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La Traviata, Act II: Germont's Aria - "Di provenza il mar, il sol" (Instrumental Version)
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La Traviata, Act II: Gypsy Chorus (Instrumental Version)
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Nabucco, Act III: Va pensiero (Chorus of the Hebrew Slaves)
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Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe9719e6b531ac1be95bfc24d133d68993aa771e0b1d0b9fa26a2eceb13345f79. Chain 2 (Bitcoin): anchored in block 960448 (2026-07-31T18:48:12Z), 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/US2TL0924016.