{"product_id":"6sn7gta-nos-sylvania-chrome-top-matched-sextet-same-production-code-low-noise-microphonics-amplitrex-tested","title":"6SN7GTA NOS SYLVANIA Chrome Top Matched Sextet - Same Production Code - Low Noise \u0026 Microphonics - AMPLITREX Tested","description":"\u003ch3 data-pm-slice=\"1 3 []\"\u003e\u003cstrong\u003e\u003cspan\u003e6SN7GTA NOS SYLVANIA – Short Base Chrome Top – Black Plates – Matched Sextet – Made in USA 1955\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eAMPLITREX Tested – VERY STRONG – Matched Sextet – Low Noise \u0026amp; Microphonics\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003e\u003cspan\u003eRisultati dei Test:\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cspan\u003eValvole testate su \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eAmplitrex AT-1000 Tube Tester\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e:\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eCondizioni di Test:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Va = 250V; Vg = -8V\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eMedia 100%:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 9.0 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eRisultato del Test:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e MOLTO FORTE\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eRange del sestetto sulle medie delle valvole:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600–2600; Ia = 7.6–7.8 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eMatched Score:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e 2.60 – Abbinamento eccellente\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eValvola #6\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 1:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 7.6 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 2:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 7.6 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eValvola #37\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 1:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 7.8 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 2:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 7.4 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eValvola #35\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 1:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 7.6 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 2:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 7.8 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eValvola #4\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 1:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2500; Ia = 7.4 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 2:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2700; Ia = 8.0 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eValvola #7\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 1:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 7.6 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 2:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 8.0 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eValvola #8\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 1:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 7.6 mA\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eSezione 2:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Gm = 2600; Ia = 8.0 mA\u003c\/span\u003e\n\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.\u003cbr\u003e\n\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\u003eEccezionale \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003esestetto NOS di 6SN7GTA Sylvania\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, prodotto negli Stati Uniti nel \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e1955\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e e accuratamente selezionato come \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eMatched Sextet\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. Tutti e sei gli esemplari condividono l'identico codice di fabbricazione \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e288 \/ 513\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, riconducibile alla 13ª settimana del 1955, e presentano la caratteristica costruzione \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eShort Base Chrome Top con Black Plates\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. Un insieme particolarmente interessante per la sua omogeneità costruttiva e l'appartenenza alla medesima produzione americana Sylvania degli anni ’50.\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 rivelano un abbinamento di notevole precisione. Tutte e sei le valvole presentano una transconduttanza media identica di \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e2600 µmhos\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, corrispondente al riferimento nominale, mentre le correnti anodiche medie sono concentrate nell'intervallo estremamente ristretto di \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e7,6–7,8 mA\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. Considerando le singole sezioni, la transconduttanza varia da 2500 a 2700 µmhos e la corrente anodica da 7,4 a 8,0 mA. Il \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eMatched Score di 2,60\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e conferma l'eccellente uniformità complessiva, una caratteristica particolarmente significativa per un gruppo di sei valvole vintage.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eOgni esemplare ha superato \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e48 ore di burn-in e verifica della stabilità\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, dimostrando un'emissione molto forte e costante, senza fluttuazioni, cortocircuiti o presenza di gas. I controlli hanno inoltre confermato livelli di rumore e microfonicità molto bassi, con selezione speciale \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eGreen Dot e Gray Dot\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. Un insieme di verifiche che valorizza ulteriormente il sestetto, offrendo caratteristiche documentate anche per applicazioni audio particolarmente sensibili.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eLe \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e6SN7GTA Sylvania\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e trovano impiego in preamplificatori hi-fi, amplificatori per cuffie, stadi driver, buffer e circuiti phase inverter compatibili. L'eccezionale uniformità del gruppo lo rende particolarmente interessante per apparecchiature che richiedono più valvole con caratteristiche elettriche coerenti. La produzione Sylvania di questo periodo è inoltre tradizionalmente apprezzata dagli audiofili per una presentazione musicale generalmente descritta come \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eaperta, dinamica e naturale\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, con buona trasparenza e definizione.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eRiunire \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003esei esemplari NOS della medesima settimana di produzione del marzo 1955\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, con marcature originali ottimamente conservate, condizioni estetiche eccellenti e medie di transconduttanza identiche, costituisce un'opportunità di particolare interesse. Un \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eMatched Sextet Sylvania originale degli anni ’50\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e che unisce autenticità storica, accuratezza dell'abbinamento e stabilità verificata: una scelta ricercata per chi desidera equipaggiare il proprio sistema audio con un insieme vintage coerente e accuratamente selezionato.\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":59659409916252,"sku":"03901","price":2339.0,"currency_code":"PLN","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0616\/3775\/5127\/files\/1_0bf4a4cf-7267-49de-b155-9205d7f7b762.jpg?v=1793112520","url":"https:\/\/vacuumtubestreasures.com\/it-pl\/products\/6sn7gta-nos-sylvania-chrome-top-matched-sextet-same-production-code-low-noise-microphonics-amplitrex-tested","provider":"Vacuum Tubes Treasures","version":"1.0","type":"link"}