{"product_id":"6sn7gta-nos-sylvania-chrome-top-matched-quad-same-production-code-low-noise-microphonics-amplitrex-tested-1","title":"6SN7GTA NOS SYLVANIA Chrome Top Matched Quad - Same Production Code - Low Noise \u0026 Microphonics - AMPLITREX Tested","description":"\u003ch3 class=\"p1\"\u003e\u003cb\u003e6SN7GTA NOS SYLVANIA – \u003cmeta charset=\"utf-8\"\u003e \u003cspan\u003eShort \u003c\/span\u003e\u003cspan\u003eBase \u003c\/span\u003e\u003cspan\u003eChrome \u003c\/span\u003e\u003cspan\u003eTop\u003c\/span\u003e – Matched Quad – Same Data Codes – Made in USA 1955\u003c\/b\u003e\u003c\/h3\u003e\n\u003cp class=\"p1\"\u003e\u003cb\u003eAMPLITREX Tested – VERY STRONG – \u003cmeta charset=\"utf-8\"\u003e \u003cspan\u003eGreen Dot \u0026amp; Gray Dot \u003cmeta charset=\"utf-8\"\u003e– \u003c\/span\u003eLow Noise \u0026amp; Microphonics\u003c\/b\u003e\u003c\/p\u003e\n\u003ch3 data-start=\"3046\" data-end=\"3436\"\u003e\u003cstrong\u003eRisultati dei Test:\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eValvole testate su \u003cstrong\u003eAmplitrex AT-1000 Tube tester\u003c\/strong\u003e:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCondizioni di Test:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eVa = 250V, Vg = -8V\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eMedia 100% Gm = 2600 ; Ia = 9.0 mA\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRisultato del Test:\u003c\/strong\u003e MOLTO FORTE\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"p1\"\u003e\u003cb\u003eValvola #18\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli class=\"p1\"\u003eSezione 1: Gm = \u003cmeta charset=\"utf-8\"\u003e2600 ; Ia = 7.8 mA\u003c\/li\u003e\n\u003cli class=\"p1\"\u003eSezione 2: Gm = 2700 ; Ia = 8.2 mA\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"p1\"\u003e\u003cb\u003eValvola #26\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli class=\"p1\"\u003eSezione 1: Gm = 2600 ; Ia = 7.6 mA\u003c\/li\u003e\n\u003cli class=\"p1\"\u003eSezione 2: Gm = 2700 ; Ia = 8.6 mA\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"p1\"\u003e\u003cb\u003eValvola #14\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli class=\"p1\"\u003eSezione 1: Gm = 2600 ; Ia = 7.6 mA\u003c\/li\u003e\n\u003cli class=\"p1\"\u003eSezione 2: Gm = 2800 ; Ia = 8.6 mA\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"p1\"\u003e\u003cb\u003eValvola #33\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli class=\"p1\"\u003eSezione 1: Gm = 2700 ; Ia = 8.0 mA\u003c\/li\u003e\n\u003cli class=\"p1\"\u003eSezione 2: Gm = 2700 ; Ia = 8.2 mA\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 class=\"p1\"\u003e\u003cb\u003eTest addizionali:\u003c\/b\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli class=\"p1\"\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003eBurn-in \/ Stability Test:\u003c\/b\u003e 48h – OK\u003c\/span\u003e\u003c\/li\u003e\n\u003cli class=\"p1\"\u003e\n\u003cspan class=\"s1\"\u003e\u003cb\u003eMicrofonicità e rumore:\u003c\/b\u003e\u003c\/span\u003e Molto Bassi. Testate e conformi per l’impiego in apparecchiature hi-fi e amplificatori per chitarra, anche negli stadi audio più sensibili.\u003c\/li\u003e\n\u003cli class=\"p1\"\u003e\n\u003cspan class=\"s1\"\u003e\u003cb\u003eBilanciamento:\u003c\/b\u003e\u003c\/span\u003e Molto buono. Le sezioni risultano coerenti e ben allineate, rendendo la valvola idonea anche all’impiego come phase inverter in applicazioni hi-fi e strumentali.\u003c\/li\u003e\n\u003cli class=\"p1\"\u003e\n\u003cspan class=\"s1\"\u003e\u003cb\u003eEmissione:\u003c\/b\u003e\u003c\/span\u003e Eccellente – Emissione molto forte e stabile, senza fluttuazioni.\u003c\/li\u003e\n\u003cli class=\"p1\"\u003e\n\u003cb\u003eCortocircuiti \/ Gas:\u003c\/b\u003e\u003cspan class=\"s1\"\u003e assenti\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 class=\"p1\"\u003e\u003cb\u003eDescrizione\u003c\/b\u003e\u003c\/h3\u003e\n\u003cp data-pm-slice=\"1 1 []\"\u003e\u003cspan\u003ePregiato \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003equartetto NOS di 6SN7GTA Sylvania\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, prodotto negli Stati Uniti nel 1955 e accuratamente selezionato come \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eMatched Quad\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. Tutti e quattro gli esemplari condividono il medesimo codice di fabbricazione \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e288 \/ 513\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e e presentano la ricercata costruzione \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eShort Base con Chrome Top, placche nere e getter superiore\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, tipica della produzione americana Sylvania di questo periodo.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eLe misurazioni effettuate con \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eAmplitrex AT-1000\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e evidenziano prestazioni molto forti e un’eccellente uniformità elettrica del gruppo. Le otto sezioni misurate presentano valori di transconduttanza compresi tra \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eGm 2600 e 2800\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, con correnti anodiche comprese tra \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e7,6 e 8,6 mA\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e: risultati particolarmente coerenti per un quartetto NOS risalente allo stesso lotto produttivo.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eOgni valvola è stata sottoposta a \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e48 ore di burn-in e verifica della stabilità\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, oltre a controlli specifici di rumore e microfonicità. La selezione \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eGreen Dot e Gray Dot\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e identifica esemplari caratterizzati da \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003erumore e microfonicità molto bassi\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, idonei anche agli stadi audio più sensibili.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eGrazie all’abbinamento elettrico, alla provenienza dallo stesso lotto e all’elevata qualità della selezione, questo quartetto rappresenta una scelta ideale per \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003epreamplificatori, amplificatori per cuffie, circuiti bilanciati, stadi driver, buffer e phase inverter\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, nonché per apparecchiature hi-fi che richiedono quattro 6SN7 dalle caratteristiche coerenti.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eQueste 6SN7GTA conservano le qualità tradizionalmente associate alla migliore produzione Sylvania: una riproduzione \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eaperta, dinamica e naturale\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, con eccellente trasparenza, definizione e controllo.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eUn \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eraro Matched Quad NOS dello stesso lotto di produzione\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, risalente alla \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e13ª settimana del 1955\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, destinato agli appassionati più esigenti e ai collezionisti alla ricerca di autentiche valvole Sylvania americane, accuratamente testate e selezionate.\u003c\/span\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3 class=\"p1\"\u003e\u003cstrong\u003eCondizioni\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli class=\"p1\"\u003e\n\u003cspan class=\"s1\"\u003e\u003cb\u003eCondizioni:\u003c\/b\u003e\u003c\/span\u003e NOS - New Old Stock - Testata e funzionante - Fornite in nostra scatola personalizzata per una protezione ottimale.\u003c\/li\u003e\n\u003cli class=\"p1\"\u003e\n\u003cspan class=\"s1\"\u003e\u003cb\u003eFunzionalità:\u003c\/b\u003e\u003c\/span\u003e Perfettamente operativa\u003c\/li\u003e\n\u003cli class=\"p1\"\u003e\n\u003cspan class=\"s1\"\u003e\u003cb\u003eCondizioni estetiche:\u003c\/b\u003e\u003c\/span\u003e Eccellenti – Scritte ottimamente conservate, minimi segni del tempo. Vedi foto per i dettagli.\u003c\/li\u003e\n\u003cli class=\"p1\"\u003e\n\u003cmeta charset=\"utf-8\"\u003e \u003cstrong\u003eSelezione \u003c\/strong\u003e\u003cspan\u003e\u003cstrong\u003especiale:\u003c\/strong\u003e \u003c\/span\u003e\u003cstrong\u003e\u003cmeta charset=\"utf-8\"\u003e\u003c\/strong\u003e\u003cspan\u003eGreen \u003c\/span\u003e\u003cspan\u003eDot \u003c\/span\u003e\u003cspan\u003ee \u003c\/span\u003e\u003cspan\u003eGray \u003c\/span\u003e\u003cspan\u003eDot, \u003c\/span\u003e\u003cspan\u003econ \u003c\/span\u003e\u003cspan\u003ebasso \u003c\/span\u003e\u003cspan\u003erumore \u003c\/span\u003e\u003cspan\u003ee \u003c\/span\u003e\u003cspan\u003emicrofonicità \u003c\/span\u003e\u003cspan\u003everificati \u003c\/span\u003e\u003cspan\u003emediante \u003c\/span\u003e\u003cspan\u003eAmplitrex \u003c\/span\u003e\u003cspan\u003eAT-1000.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCodice di fabbricazione:\u003c\/strong\u003e Sylvania Electric Products Inc., USA – marcatura originale sulla base 288 \/ 513. 288 codice Sylvania Interno. 513 - 13ª settimana del 1955 (marzo 1955).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003e\u003ca rel=\"noopener\" title=\"Perché le nostre valvole sono diverse – il protocollo VTT che migliora suono, affidabilità e durata\" href=\"https:\/\/vacuumtubestreasures.com\/blogs\/notizie\/perche-le-nostre-valvole-sono-diverse\" target=\"_blank\"\u003e\u003cstrong\u003eScopra perché le nostre valvole sono diverse →\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"SYLVANIA","offers":[{"title":"Default Title","offer_id":59662474019164,"sku":"03902","price":359.8,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0616\/3775\/5127\/files\/1_6dff86d7-7033-41a7-960f-6c03b03941dc.jpg?v=1793124070","url":"https:\/\/vacuumtubestreasures.com\/it-si\/products\/6sn7gta-nos-sylvania-chrome-top-matched-quad-same-production-code-low-noise-microphonics-amplitrex-tested-1","provider":"Vacuum Tubes Treasures","version":"1.0","type":"link"}