{"product_id":"12ax7-ecc83-sylvania-long-gray-plates-square-getter-tested-tube-made-in-usa","title":"12AX7 \/ ECC83 SYLVANIA Long Gray plates Square Getter Tested Tube Made in USA","description":"\u003ch3\u003e\n\n\u003cmeta charset=\"utf-8\"\u003e \u003cstrong\u003e12AX7 \/ ECC83 Baldwin by SYLVANIA Long Gray plates Square Getter Tested Tube \u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003eMade in USA\u003c\/strong\u003e\n\n\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eAMPLITREX Tested – STRONG – Vintage American Sylvania Production\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 = -2V\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003e100% Average:\u003c\/strong\u003e\u003cspan\u003e Gm = 1600 ; Ia = 1.2 mA\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eTest Result:\u003c\/strong\u003e 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 Gm = 1400 ; Ia = 0.9 mA\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eSection 2:\u003c\/strong\u003e\u003cspan\u003e Gm = 1500 ; Ia = \u003cmeta charset=\"utf-8\"\u003e0.9 mA\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cdiv\u003e\u003cstrong\u003eAdditional tests performed:\u003c\/strong\u003e\u003c\/div\u003e\n\u003cul\u003e\n\n\u003cli\u003e\u003cspan\u003e\u003cstrong\u003eBurn-in \/ Stability Test:\u003c\/strong\u003e 48h – 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, even 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-matched, making the tube suitable even 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 Strong – Strong and steady emission, suitable for any application.\u003c\/span\u003e\u003c\/li\u003e\n\n\u003cli\u003e\u003cspan\u003e\u003cstrong\u003eShorts and GAS:\u003c\/strong\u003e None.\u003c\/span\u003e\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eDescription\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp data-pm-slice=\"1 1 []\"\u003e\u003cspan\u003eA unique and rare \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e12AX7 \/ ECC83 Baldwin produced by Sylvania\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, characterized by its sought-after \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eLong Gray Plates and Square Getter\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e construction. This configuration is typical of early American production and decidedly less common than the later versions with short plates and halo getters; it is interesting both for audio use and for vintage tube collectors.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp data-pm-slice=\"1 1 []\"\u003e\u003cspan\u003eThe code \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e312 952\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e identifies \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eSylvania Electric Products Inc., Emporium, Pennsylvania\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, and places the manufacture in the \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e52nd week of 1959\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. The Baldwin branding indicates the OEM destination for the well-known American manufacturer's equipment, while the internal features clearly point to original Sylvania production.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eAfter a \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e48-hour burn-in\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e cycle, the tube was tested with an \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eAmplitrex AT-1000\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, recording \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eGm 1400 with Ia 0.9 mA\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e for the first section and \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eGm 1500 with Ia 0.9 mA\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e for the second. The emission is \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003estrong, steady, and stable\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, with transconductance values close to the nominal reference.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003every good balance\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e is one of the specimen's main strengths. The plate currents are perfectly matched and the difference in Gm is minimal, making the tube suitable even 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 consistency and good symmetry between sections are required.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003elow microphonics\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e selection allows for its use even in the most sensitive audio stages of hi-fi equipment and guitar amplifiers. From a sonic perspective, 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 \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003evintage Made in USA 12AX7 \/ ECC83\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e that is particularly interesting for its origin and construction: 1959 Sylvania production, Baldwin branding, Long Gray Plates, Square Getter, and well-matched sections. Tested, fully functional, and free of shorts or gas, it is ready to return to service in compatible equipment.\u003c\/span\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cstrong\u003eCondition:\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eCondition:\u003c\/strong\u003e\u003cspan\u003e Vintage Tubes - Tested and fully functional. Supplied in our custom box for optimal protection.\u003c\/span\u003e\u003cstrong\u003e\u003cbr\u003e\u003c\/strong\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eFunctionality: \u003c\/strong\u003eFully 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\u003cspan\u003e Good – Markings are clearly legible with slight signs of aging. See photos for details.\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eManufacturing Code:\u003c\/strong\u003e 312 952 → 312 indicates the manufacturer, Sylvania Electric Products Inc., Emporium, Pa. - 952 → 9 (of three digits) → 1959 - 52 → 52nd 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=\"Why our tubes are different – the VTT protocol that improves sound, reliability, and lifespan\" 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":59596906070364,"sku":"03886","price":459.0,"currency_code":"CNY","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0616\/3775\/5127\/files\/2_765427c8-5bc8-4545-b8bc-4e5ca9af9fa6.jpg?v=1792490849","url":"https:\/\/vacuumtubestreasures.com\/en-cn\/products\/12ax7-ecc83-sylvania-long-gray-plates-square-getter-tested-tube-made-in-usa","provider":"Vacuum Tubes Treasures","version":"1.0","type":"link"}