{"product_id":"12ax7-ecc83-nos-sylvania-gray-plates-halo-getter-amplitrex-tested-tube-usa","title":"12AX7 \/ ECC83 NOS SYLVANIA Gray Plates Halo Getter Amplitrex Tested Tube USA","description":"\u003cp\u003e\u003cstrong\u003e12AX7 \/ ECC83 NOS SYLVANIA Gray Plates Halo Getter Made in USA '66\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eLow Noise \u0026amp; Microphonics –\u003cspan\u003e VERY STRONG - Balanced Sections - Vintage American \u003cmeta charset=\"utf-8\"\u003eSYLVANIA Production\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eTest Results:\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eTube tested on \u003cstrong\u003eAMPLITREX AT-1000 \u003c\/strong\u003eTube Tester:\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eTest Conditions:\u003c\/strong\u003e\u003cspan\u003e Va = 250V ; Vg = -3V\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eAverage 100%:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eGm = 1200 ; Ia = 1.0 mA\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eTest Result:\u003c\/strong\u003e VERY STRONG\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eTube :\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eSection 1:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eGm = 1700 ; Ia = 1.2 mA\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eSection 2:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eGm = 1700 ; Ia = 1.1 mA\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cdiv\u003e\n\n\u003cmeta charset=\"utf-8\"\u003e\n\n\u003cdiv\u003e\u003cstrong\u003eAdditional Tests performed:\u003c\/strong\u003e\u003c\/div\u003e\n\n\u003cul\u003e\n\n\u003cli\u003e\u003cspan\u003e\u003cstrong\u003eBurn-in \/ Stability Test: \u003c\/strong\u003e48h – OK\u003c\/span\u003e\u003c\/li\u003e\n\n\u003cli\u003e\u003cspan\u003e\u003cstrong\u003eMicrophonics:\u003c\/strong\u003e Low. Tested and compliant for use in hi-fi equipment and guitar amplifiers, including in the most sensitive audio stages.\u003c\/span\u003e\u003c\/li\u003e\n\n\u003cli\u003e\u003cspan\u003e\u003cstrong\u003eBalance:\u003c\/strong\u003e Very good. The sections are consistent and well-aligned, making the tube also suitable for use as a phase inverter in hi-fi and instrumental applications.\u003c\/span\u003e\u003c\/li\u003e\n\n\u003cli\u003e\u003cspan\u003e\u003cstrong\u003eEmission Quality:\u003c\/strong\u003e Excellent – Very strong and stable emission, without fluctuations.\u003c\/span\u003e\u003c\/li\u003e\n\n\u003cli\u003e\u003cspan\u003e\u003cstrong\u003eShort Circuits and GAS:\u003c\/strong\u003e None.\u003c\/span\u003e\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\n\u003c\/div\u003e\n\u003ch3\u003e\u003cstrong\u003eDescription:\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp data-pm-slice=\"1 1 []\"\u003e\u003cspan\u003eThis \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e12AX7 \/ ECC83 NOS Sylvania\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e is an excellent example of American vacuum tube production from the 1960s. Manufactured at the Sylvania plant in Emporium, Pennsylvania, it features the characteristic construction with \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003egray plates and a halo getter\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, accompanied by a robust and precise internal assembly.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe code \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e643\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e identifies \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eSylvania Electric Products Inc.\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e and dates the manufacturing to the \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e43rd week of 1966\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. The tube is in excellent cosmetic condition, with markings well-preserved and only minimal signs due to the long storage period.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eTested with an \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eAmplitrex AT-1000\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e after a 48-hour burn-in cycle, it recorded \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eGm 1700 in both sections\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, with anode currents of \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e1.2 and 1.1 mA\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, respectively. The results highlight \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003every strong, stable emission, free of fluctuations\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, accompanied by extremely uniform electrical behavior.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eexcellent balance\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e is one of the main strengths of this specimen. The perfect match in transconductance and minimal difference in anode current make the tube particularly suitable as a \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003ephase inverter\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, as well as a driver or in stages where precision and symmetry between sections are required.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003elow noise and microphonics\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e selection allows it to be used even in the most sensitive audio stages of hi-fi equipment and guitar amplifiers. Sonically, this Sylvania production is appreciated for an \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eopen, dynamic, and natural\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e presentation, with good definition, controlled response, and a convincing balance across the entire audio range.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eA particularly valuable \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e12AX7 \/ ECC83 NOS Made in USA\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e for its state of preservation, emission, and balance: 1966 Sylvania production, gray plates, halo getter, and almost perfectly matched sections. Tested, perfectly operational, and free of short circuits or gas, it represents a quality choice for hi-fi systems and compatible tube amplifiers.\u003c\/span\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cstrong\u003eConditions:\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eCondition:\u003c\/strong\u003e NOS - New Old Stock - Tested and functional - Supplied in our custom box for optimal protection. \u003cstrong\u003e\u003cbr\u003e\u003c\/strong\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eFunctionality: \u003c\/strong\u003ePerfectly operational.\u003cstrong\u003e\u003cbr\u003e\u003c\/strong\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eCosmetic Condition:\u003c\/strong\u003e Excellent – Markings well-preserved, minimal signs of aging. See photos for details.\u003cstrong\u003e\u003cbr\u003e\u003c\/strong\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eManufacturing Code:\u003c\/strong\u003e 643 → Sylvania Electric Products Inc., Emporium, Pa. - \u003cmeta charset=\"utf-8\"\u003e643 → 6 (of three digits) → 1966 - 43 → 43rd week of the year\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003e\u003ca href=\"https:\/\/vacuumtubestreasures.com\/blogs\/notizie\/perche-le-nostre-valvole-sono-diverse\" title=\"Perché le nostre valvole sono diverse – il protocollo VTT che migliora suono, affidabilità e durata\" rel=\"noopener\" target=\"_blank\"\u003e\u003cstrong\u003eDiscover why our tubes are different →\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"SYLVANIA","offers":[{"title":"Default Title","offer_id":59596672729436,"sku":"03885","price":81.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0616\/3775\/5127\/files\/2_b8fc66ec-8701-4f48-a346-a9f4dd446a92.jpg?v=1792488365","url":"https:\/\/vacuumtubestreasures.com\/en-us\/products\/12ax7-ecc83-nos-sylvania-gray-plates-halo-getter-amplitrex-tested-tube-usa","provider":"Vacuum Tubes Treasures","version":"1.0","type":"link"}