{"product_id":"12ax7-ecc83-nos-heinz-kauffman-gray-plates-foil-dimpled-getter-made-in-usa-50s-amplitrex-tested-low-noise","title":"12AX7 \/ ECC83 NOS Heinz \u0026 Kauffman – Gray Plates Foil Dimpled Getter – Made in USA '50s – AMPLITREX Tested – Low Noise","description":"\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003e \u003cstrong\u003e12AX7 \/ ECC83 NOS Heinz \u0026amp; Kauffman – Gray Plates – Foil Dimpled Getter – Made in USA – AMPLITREX Tested\u003c\/strong\u003e\u003cbr\u003e\u003c\/p\u003e\n\n\u003ch3\u003e \u003cstrong\u003eDescription:\u003c\/strong\u003e\n\u003c\/h3\u003e\n\n\u003cp class=\"p1\"\u003e This \u003cspan class=\"s1\"\u003e\u003cb\u003eNOS 12AX7 \/ ECC83 marked Heinz \u0026amp; Kauffman\u003c\/b\u003e\u003c\/span\u003e , made in the \u003cspan class=\"s1\"\u003e\u003cb\u003eUSA in the 1950s\u003c\/b\u003e\u003c\/span\u003e , belongs to the tradition of American signal tubes made to very high construction standards.\u003c\/p\u003e\n\n\u003cp class=\"p1\"\u003e The \u003cspan class=\"s1\"\u003e\u003cb\u003eHeinz \u0026amp; Kauffman\u003c\/b\u003e\u003c\/span\u003e brand was used by a well-known American distributor who selected and rebranded valves produced by major American factories of the time. The available examples feature internal construction typical of 1950s American production, characterized by meticulous mechanical engineering and high-quality materials.\u003c\/p\u003e\n\n\u003cp class=\"p1\"\u003e The internal structure includes:\u003c\/p\u003e\n\n\u003cul\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003eGray Plates\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003eFoil Dimpled Getter\u003c\/b\u003e\n\u003c\/li\u003e\n\n \u003cli class=\"p1\"\u003erobust construction typical of American productions of the period\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\u003cp class=\"p1\"\u003e The valve is in \u003cspan class=\"s1\"\u003e\u003cb\u003eshowcase aesthetic condition\u003c\/b\u003e\u003c\/span\u003e , with well-preserved silkscreen prints and a perfectly intact internal structure.\u003c\/p\u003e\n\n\u003cp class=\"p1\"\u003e It has been \u003cspan class=\"s1\"\u003e\u003cb\u003eindividually tested in our laboratory with AMPLITREX AT-1000\u003c\/b\u003e\u003c\/span\u003e , checking emission, stability and operational behavior.\u003c\/p\u003e\n\n\u003cp data-end=\"1220\" data-start=\"915\"\u003e \u003cstrong data-end=\"943\" data-start=\"917\"\u003eSound Characteristics\u003c\/strong\u003e\u003cbr data-end=\"946\" data-start=\"943\"\u003e\u003c\/p\u003e\n\n\u003cp class=\"p1\"\u003e The \u003cspan class=\"s1\"\u003e\u003cb\u003eAmerican 12AX7s from the 1950s\u003c\/b\u003e\u003c\/span\u003e are known for a balanced, natural and very musical sound presentation.\u003c\/p\u003e\n\n\u003cp class=\"p3\"\u003e \u003cb\u003eBass:\u003c\/b\u003e Precise and well-controlled. The low range maintains good depth without losing definition.\u003c\/p\u003e\n\n\u003cp class=\"p3\"\u003e \u003cb\u003eMids:\u003c\/b\u003e Rich and natural. Vocals sound very believable, and instruments like piano, strings, and acoustic guitar emerge with excellent harmonic balance.\u003c\/p\u003e\n\n\u003cp class=\"p3\"\u003e \u003cb\u003eHighs:\u003c\/b\u003e Clean and well-extended. The high end maintains a fine grain that promotes smooth, natural listening.\u003c\/p\u003e\n\n \u003cp class=\"p3\"\u003e\u003cb\u003eDynamics:\u003c\/b\u003e Very responsive. The tube precisely follows the variations in the musical signal while maintaining good microdynamics.\u003c\/p\u003e\n\n\u003cp class=\"p3\"\u003e \u003cb\u003eSoundstage:\u003c\/b\u003e Stable and well-organized soundstage, with natural separation of instruments.\u003c\/p\u003e\n\n\u003cp class=\"p3\"\u003e \u003cspan class=\"s1\"\u003e🎧\u003c\/span\u003e \u003cb\u003eUse in Hi-Fi Stereo Amplifiers\u003c\/b\u003e\u003c\/p\u003e\n\n\u003cp class=\"p1\"\u003e The \u003cspan class=\"s1\"\u003e\u003cb\u003e12AX7 \/ ECC83\u003c\/b\u003e\u003c\/span\u003e is one of the most popular signal tubes in audio equipment design.\u003c\/p\u003e\n\n\u003cp class=\"p1\"\u003e It is used in:\u003c\/p\u003e\n\n\u003cul\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003etube preamplifiers\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003ephono stages\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003eamplifier drivers\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e integrated amplifiers and vintage equipment\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\u003cp class=\"p1\"\u003e Thanks to its \u003cspan class=\"s1\"\u003e\u003cb\u003elow microphonics and low noise\u003c\/b\u003e\u003c\/span\u003e , this specimen is also suitable for \u003cspan class=\"s1\"\u003e\u003cb\u003esensitive circuit positions\u003c\/b\u003e\u003c\/span\u003e , where stability and quietness are particularly important.\u003c\/p\u003e\n\n\u003cp class=\"p3\"\u003e \u003cspan class=\"s1\"\u003e🎸\u003c\/span\u003e \u003cb\u003eUse in Music Amplifiers\u003c\/b\u003e\u003c\/p\u003e\n\n\u003cp class=\"p1\"\u003e The \u003cspan class=\"s1\"\u003e\u003cb\u003eECC83\/12AX7\u003c\/b\u003e\u003c\/span\u003e is one of the most widely used tubes in musical instrument amplifiers.\u003c\/p\u003e\n\n \u003cp class=\"p1\"\u003eVintage American valves generally offer:\u003c\/p\u003e\n\n\u003cul\u003e\n\n\u003cli class=\"p1\"\u003e excellent midrange definition\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e good dynamic response\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e great touch sensitivity\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\u003cp class=\"p1\"\u003e Qualities that allow for an articulate and musical sound in guitar circuits.\u003c\/p\u003e\n\n\u003cp class=\"p3\"\u003e \u003cspan class=\"s1\"\u003e🎯\u003c\/span\u003e \u003cb\u003eNote for audiophiles and technicians\u003c\/b\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003eHeinz \u0026amp; Kauffman – USA production 1950s\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003e12AX7 \/ ECC83 NOS\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003eGray Plates – Foil Dimpled Getter\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003eShowcase aesthetic conditions\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003eAMPLITREX AT-1000 Tested\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003eLow Noise \u0026amp; Microphonics\u003c\/b\u003e\n\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e \u003cb\u003eRating: VERY STRONG\u003c\/b\u003e\n\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\u003cp class=\"p3\"\u003e A \u003cspan class=\"s2\"\u003e\u003cb\u003evintage American signal tube\u003c\/b\u003e\u003c\/span\u003e , built to the quality standards of 1950s production, capable of offering \u003cspan class=\"s2\"\u003e\u003cb\u003eoperational stability, silence and a natural and balanced sound presentation\u003c\/b\u003e\u003c\/span\u003e , qualities that continue to make it highly appreciated by \u003cspan class=\"s2\"\u003e\u003cb\u003eaudiophiles, technicians and musicians\u003c\/b\u003e\u003c\/span\u003e .\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch3\u003e \u003cstrong\u003eTest Results:\u003c\/strong\u003e\n\u003c\/h3\u003e\n\n \u003cp\u003eValve tested on\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eAMPLITREX AT-1000\u003cspan\u003e \u003c\/span\u003e\u003c\/strong\u003eTube Tester:\u003c\/p\u003e\n\n\u003cul\u003e\n\n\u003cli\u003e\n\n \u003cstrong\u003eTest Conditions:\u003c\/strong\u003e \u003cspan\u003eVa = 250V ; Vg = -2V\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 = 1600 ; Ia = 1.2 mA\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\n\u003cp\u003e \u003cstrong\u003eValve:\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n\n\u003cli\u003e\n\n \u003cstrong\u003eSection 1:\u003c\/strong\u003e \u003cspan\u003eGm = 1600 ; Ia = 1.3 mA\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n \u003cstrong\u003eSection 2:\u003c\/strong\u003e \u003cspan\u003eGm = 1500 ; Ia = 1.1 mA\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\u003cdiv\u003e \u003cstrong\u003eAdditional Tests Performed:\u003c\/strong\u003e\n\u003c\/div\u003e\n\n\u003cul\u003e\n\n\u003cli\u003e \u003cspan\u003e\u003cstrong\u003eMicrophonics:\u003c\/strong\u003e Low. Tested and approved for use in hi-fi, phono stages, and guitar amplifiers, including V1.\u003c\/span\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e \u003cspan\u003e\u003cstrong\u003eBalance:\u003c\/strong\u003e The two sections show coherent and well-aligned values, making the valve also ideal as a phase inverter in hi-fi and instrumental applications.\u003c\/span\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e \u003cspan\u003e\u003cstrong\u003eOutput Quality:\u003c\/strong\u003e Excellent – ​​Very strong and stable output, no fluctuations.\u003c\/span\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e \u003cspan\u003e\u003cstrong\u003eShort circuits and GAS:\u003c\/strong\u003e Absent.\u003c\/span\u003e\n\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n \u003ch3\u003e\u003cstrong\u003eConditions:\u003c\/strong\u003e\u003c\/h3\u003e\n\n\u003cul\u003e\n\n\u003cli\u003e\n\n \u003cstrong\u003eCondition:\u003c\/strong\u003e NOS - New Old Stock - Tested and working - 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\u003e Fully functional.\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\u003eExcellent – ​​Excellently preserved lettering, minimal signs of wear. See photos for details.\u003c\/span\u003e\u003cstrong\u003e\u003cbr\u003e\u003c\/strong\u003e\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n \u003cstrong\u003eManufacturing Code:\u003c\/strong\u003e \u003cspan\u003eUnreadable – Made in the USA, identifiable by construction features. 1950s\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\u003cp\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 durability\" rel=\"noopener\" target=\"_blank\"\u003e\u003cstrong\u003eFind out why our valves are different →\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"HEINTZ \u0026 KAUFMAN","offers":[{"title":"Default Title","offer_id":56991546605916,"sku":"03467","price":1377.0,"currency_code":"HKD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0616\/3775\/5127\/files\/2_14a0b374-63be-4e98-92df-5eb57cb894ce.jpg?v=1773408933","url":"https:\/\/vacuumtubestreasures.com\/en-hk\/products\/12ax7-ecc83-nos-heinz-kauffman-gray-plates-foil-dimpled-getter-made-in-usa-50s-amplitrex-tested-low-noise","provider":"Vacuum Tubes Treasures","version":"1.0","type":"link"}