{"product_id":"12ax7-ecc83-rca-long-black-plates-square-tilt-getter-balanced-low-noise-mic-made-in-usa-58","title":"12AX7 \/ ECC83 RCA Long Black Plates Square Tilt getter - Balanced - Low Noise \u0026 Mic - Made in USA '58","description":"\u003cp\u003e\u003cstrong\u003e12AX7 \/ ECC83 RCA Long Black Plates Square Tilt getter Made in USA '58\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"p2\"\u003e\u003cb\u003eAMPLITREX Tested – Low Noise \u0026amp; Microphonics – Balanced Sections - Vintage American Black Plates\u003c\/b\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eDescription:\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp class=\"p1\"\u003eThis \u003cspan class=\"s1\"\u003e\u003cb\u003e12AX7 \/ ECC83 RCA\u003c\/b\u003e\u003c\/span\u003e, \u003cspan class=\"s1\"\u003e\u003cb\u003eMade in USA 1958\u003c\/b\u003e\u003c\/span\u003e production, represents one of the most fascinating and sought-after configurations from the golden age of American small signal tubes.\u003c\/p\u003e\n\u003cp class=\"p1\"\u003eThe construction with \u003cspan class=\"s1\"\u003e\u003cb\u003eLong Black Plates\u003c\/b\u003e\u003c\/span\u003e and the rare \u003cspan class=\"s1\"\u003e\u003cb\u003eSquare Tilt Getter\u003c\/b\u003e\u003c\/span\u003e identifies an RCA production from the late '50s particularly appreciated for its musicality, harmonic richness, and strong sonic personality. This type is historically much loved by both audiophiles and enthusiasts of vintage musical instrument amplifiers.\u003c\/p\u003e\n\u003cp class=\"p1\"\u003eThe tube is used, carefully tested, and selected in our laboratory using the \u003cspan class=\"s1\"\u003e\u003cb\u003eAMPLITREX AT-1000 Tube Tester\u003c\/b\u003e\u003c\/span\u003e, with particular attention to low noise, contained microphonics, and operational consistency.\u003c\/p\u003e\n\u003cp class=\"p1\"\u003eFrom an aesthetic point of view, the specimen is in good condition for its age: the RCA silkscreen is partially eroded but still legible, while the internal structure retains all the typical charm of authentic 1950s American black plates.\u003c\/p\u003e\n\u003cp class=\"p2\"\u003eThe value of this tube is strongly linked to the combination of:\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003eoriginal USA RCA brand;\u003c\/li\u003e\n\n\u003cli\u003evintage 1958 production;\u003c\/li\u003e\n\n\u003cli\u003eLong Black Plates structure;\u003c\/li\u003e\n\n\u003cli\u003eSquare Tilt Getter;\u003c\/li\u003e\n\n\u003cli\u003elow noise;\u003c\/li\u003e\n\n\u003cli\u003elow microphonics;\u003c\/li\u003e\n\n\u003cli\u003eauthentic vintage American charm.\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003eSonic Characteristics\u003c\/b\u003e\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp class=\"p1\"\u003eThe 1950s RCA long black plates are renowned for a broad, musical, and harmonically rich sound presentation, with a deeply American character: full-bodied, natural, and engaging.\u003c\/p\u003e\n\u003cp class=\"p1\"\u003eThis tube clearly retains that typical vintage RCA sonic signature, capable of combining musicality, fluidity, and an extremely pleasant harmonic texture.\u003c\/p\u003e\n\u003cp\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003eBass\u003c\/b\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"p1\"\u003eThe bass range is full, round, and natural, with a good sense of body and presence. The bass maintains musicality and control without being artificially emphasized.\u003c\/p\u003e\n\u003cp\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003eMids\u003c\/b\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"p1\"\u003eThe mids are probably the most alluring aspect of this RCA production. Vocals are material, dense, and believable, while acoustic instruments and harmonics retain a rich and very musical texture.\u003c\/p\u003e\n\u003cp class=\"p1\"\u003eThere is that typical vintage American softness that makes these RCAs particularly satisfying for long listening sessions.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan class=\"s1\"\u003eTreble\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"p1\"\u003eThe high range is fluid, refined, and never aggressive. Detail remains present but naturally integrated, contributing to a relaxed and elegant listening experience.\u003c\/p\u003e\n\u003cp\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003eDynamics\u003c\/b\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"p1\"\u003eThe dynamic response appears musical and progressive, with good ability to follow harmonic and dynamic variations without stiffness or harshness.\u003c\/p\u003e\n\u003cp\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003eSoundstage\u003c\/b\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"p4\"\u003eThe soundstage is stable, airy, and well-organized. The image maintains good depth and correct instrument separation, with a very credible and engaging presentation.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003e🎧 Use in Hi-Fi Amplifiers\u003c\/b\u003e\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp class=\"p2\"\u003eThis RCA ECC83 \/ 12AX7 is particularly suitable for:\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003ehi-fi preamplifiers;\u003c\/li\u003e\n\n\u003cli\u003eline stages;\u003c\/li\u003e\n\n\u003cli\u003ephono stages;\u003c\/li\u003e\n\n\u003cli\u003evintage and modern integrated amplifiers;\u003c\/li\u003e\n\n\u003cli\u003ecompatible driver stages.\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp class=\"p4\"\u003eThe \u003cspan class=\"s1\"\u003e\u003cb\u003eLow Noise \u0026amp; Microphonics\u003c\/b\u003e\u003c\/span\u003e selection makes it very interesting also for sensitive applications and systems oriented towards musicality and tonal naturalness.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003e🎸 Use in Musical Applications\u003c\/b\u003e\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp class=\"p1\"\u003eIn the world of guitar amplifiers, 1950s RCA long black plates are considered by many enthusiasts to be among the most musical and fascinating American ECC83s ever produced.\u003c\/p\u003e\n\u003cp class=\"p2\"\u003eThis tube offers:\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003eexcellent harmonic response;\u003c\/li\u003e\n\n\u003cli\u003erich and three-dimensional mids;\u003c\/li\u003e\n\n\u003cli\u003egreat musicality;\u003c\/li\u003e\n\n\u003cli\u003enatural dynamic behavior;\u003c\/li\u003e\n\n\u003cli\u003econtained noise and low microphonics.\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp class=\"p4\"\u003eCharacteristics that make it very interesting also for use in vintage, boutique amplifiers, and studio applications.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003e🎯 Note for audiophiles and technicians\u003c\/b\u003e\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp class=\"p2\"\u003eThis tube represents a vintage American selection of strong historical and aesthetic charm, designed for those who desire an authentic 1950s USA RCA black plate with:\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003eLong Black Plates construction;\u003c\/li\u003e\n\n\u003cli\u003eSquare Tilt Getter;\u003c\/li\u003e\n\n\u003cli\u003ebalanced sections;\u003c\/li\u003e\n\n\u003cli\u003ehigh quietness;\u003c\/li\u003e\n\n\u003cli\u003elow microphonics;\u003c\/li\u003e\n\n\u003cli\u003etypical vintage RCA musicality.\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp class=\"p1\"\u003eAlthough this is a used vintage tube, its overall value remains very high due to its build quality, the rarity of its internal configuration, and the sonic character typical of the best American productions of the era.\u003c\/p\u003e\n\u003cp class=\"p4\"\u003eA 1958 RCA black plate with strong vintage American charm, selected for musicality, quietness, and sonic authenticity, according to the Vacuum Tubes Treasures philosophy.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003eTest Results\u003c\/b\u003e\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp class=\"p5\"\u003e\u003cb\u003eTested on AMPLITREX AT-1000 Tube Tester\u003c\/b\u003e\u003c\/p\u003e\n\u003cp class=\"p5\"\u003e\u003cb\u003eVoltage Test:\u003c\/b\u003e Va = 250V, Vg = -2V\u003c\/p\u003e\n\u003cp class=\"p1\"\u003e\u003cb\u003eAverage 100%:\u003c\/b\u003e Gm = 1600 ; Ia = 1.2 mA\u003c\/p\u003e\n\u003cp class=\"p5\"\u003e\u003cb\u003eTEST RESULT: GOOD\u003c\/b\u003e\u003c\/p\u003e\n\u003cp class=\"p5\"\u003e\u003cb\u003eTube:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cstrong\u003eSection 1:\u003c\/strong\u003e Gm = 1100 ; Ia = 0.8 mA\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cstrong\u003eSection 2:\u003c\/strong\u003e Gm = 1100 ; Ia = 0.8 mA\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003eAdditional Tests Performed\u003c\/b\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cb\u003eMicrophonics:\u003c\/b\u003e Low Noise \u0026amp; Microphonics – Tested and compliant for use in hi-fi systems and guitar amplifiers.\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cb\u003eBalance:\u003c\/b\u003e The sections are consistent and well-aligned, making the tube suitable for use as a phase inverter in hi-fi and instrumental applications.\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cb\u003eNoise:\u003c\/b\u003e Low and well-controlled. Silent operation in hi-fi and musical amplifiers in the intended positions.\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cb\u003eEmission Quality:\u003c\/b\u003e Strong – Strong and regular emission, suitable for any application.\u003c\/li\u003e\n\n\u003cli class=\"p3\"\u003e\n\n\u003cb\u003eShorts and GAS:\u003c\/b\u003e\u003cspan class=\"s2\"\u003e Absent.\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cspan class=\"s1\"\u003e\u003cb\u003eCondition\u003c\/b\u003e\u003c\/span\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cb\u003eCondition:\u003c\/b\u003e Vintage Tube – Tested and fully functional. Supplied in our custom box for optimal protection.\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cb\u003eFunctionality:\u003c\/b\u003e Perfectly operational.\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cb\u003eCosmetic condition:\u003c\/b\u003e Good – Lettering partially eroded but still legible. Tube body in good condition. See photos for details.\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp class=\"p5\"\u003e\u003cb\u003eManufacturing Code: \u003c\/b\u003e58-09 → RMA\/EIA Open Date Code → manufactured in the 9th week of 1958 → Radio Corporation of America, Camden, N. J.\u003c\/p\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\u003eDiscover why our tubes are different →\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"RCA","offers":[{"title":"Default Title","offer_id":57759834505564,"sku":"03615","price":9800.0,"currency_code":"ALL","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0616\/3775\/5127\/files\/2_814e7968-c209-46f9-8acf-e6381de71637.jpg?v=1780044076","url":"https:\/\/vacuumtubestreasures.com\/en-al\/products\/12ax7-ecc83-rca-long-black-plates-square-tilt-getter-balanced-low-noise-mic-made-in-usa-58","provider":"Vacuum Tubes Treasures","version":"1.0","type":"link"}