{"product_id":"5963-12au7-rca-matched-quad-long-black-plates-foil-getter-amplitrex-tested","title":"5963 ( 12AU7 ) RCA Matched Quad Long Black Plates Foil Getter AMPLITREX Tested","description":"\u003cp\u003e\u003cstrong\u003e5963 (12AU7 \/ ECC82) RCA – Matched Quad – Black Plates – Foil Getter\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eAMPLITREX Tested – Made in USA – 1956\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDescription:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThis \u003cstrong\u003ematched quartet of 5963 (12AU7 \/ ECC82) RCAs, Made in USA 1956\u003c\/strong\u003e , belongs to one of the most fascinating and musical productions of RCA of the 1950s. The construction with \u003cstrong\u003eblack plates and foil getters\u003c\/strong\u003e is typical of the superior quality series, created for professional applications and today sought after for their warm, authoritative and incredibly refined sonic character.\u003c\/p\u003e\n\u003cp\u003eThe valves are \u003cstrong\u003eAMPLITREX Tested\u003c\/strong\u003e and carefully selected as \u003cstrong\u003eMatched Quad\u003c\/strong\u003e : the overall behavior is coherent, stable and silent, with a performance that immediately conveys the feeling of a “special”, uncommon component.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cstrong\u003eBass:\u003c\/strong\u003e Compact, controlled, and well-articulated. The low end is tidy and precise, with a dry feel that promotes clarity and rhythm.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eMids:\u003c\/strong\u003e Balanced and natural. Vocals are credible and well-focused, with a harmonic texture that's typical of RCA: solid, musical, and free from excessive coloration.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eHighs:\u003c\/strong\u003e Clean and well-integrated. The highs are smooth and controlled, without harshness, with consistent detail that never becomes fatiguing.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eDynamics:\u003c\/strong\u003e Smooth and fluid. The response is prompt but composed, with predictable and stable behavior, ideal for line stages and drivers.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eSoundstage:\u003c\/strong\u003e Stable and well-organized soundstage. Good separation of sound planes and correct imaging, with an orderly and realistic presentation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-start=\"1884\" data-end=\"1924\"\u003e🎧 \u003cstrong\u003eUse in Hi-Fi Stereo Amplifiers\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-end=\"1917\" data-start=\"1906\"\u003eIdeal for:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli data-end=\"1955\" data-start=\"1920\"\u003epreamplifiers and line stages in non-critical positions\u003c\/li\u003e\n\u003cli data-end=\"1994\" data-start=\"1958\"\u003edrivers and buffers\u003c\/li\u003e\n\u003cli data-end=\"2065\" data-start=\"1997\"\u003eVintage and modern hi-fi amplifiers compatible with 12AU7 \/ 5963\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-end=\"2232\" data-start=\"2067\"\u003eParticularly suitable for non-critical or moderate gain positions, where operational stability, low overall noise and timbral coherence are required.\u003c\/p\u003e\n\u003cp data-start=\"2243\" data-end=\"2293\"\u003e🎸 \u003cstrong\u003eUse in Musical Instrument Amplifiers\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-end=\"2287\" data-start=\"2276\"\u003eSuitable for:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli data-end=\"2345\" data-start=\"2290\"\u003eGuitar and bass amplifiers in driver, phase inverter or V2\/V3 positions\u003c\/li\u003e\n\u003cli data-end=\"2384\" data-start=\"2348\"\u003eapplications where operational stability, good control and low background noise are required\u003c\/li\u003e\n\u003cli data-end=\"2436\" data-start=\"2387\"\u003euse in studios or in professional settings where low overall noise is an important requirement\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-end=\"2672\" data-start=\"2438\"\u003eIt offers reliable, controlled operation, with low noise and predictable response.\u003cbr data-end=\"2534\" data-start=\"2531\"\u003eIt is recommended to avoid using them in the most sensitive or very high-gain positions; however, they are perfectly suited to less critical stages, where they can offer reliable and consistent operation.\u003cbr\u003e\u003c\/p\u003e\n\u003cp data-start=\"2566\" data-end=\"2601\"\u003e🎯 \u003cstrong\u003eNote for audiophiles and technicians\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003eA solid and coherent quartet, designed for those seeking reliability, musicality and the classic RCA character of the 50s, without compromising on operational stability.\u003cbr\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003cp\u003e\u003cstrong\u003eTest Results:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eValve tested on \u003cstrong\u003eAMPLITREX AT-1000\u003c\/strong\u003e Tube Tester:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cstrong\u003eTest Conditions:\u003c\/strong\u003e Va = 250V ; Vg = -8.5V\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eAverage 100%:\u003c\/strong\u003e Gm = 2200 ; Ia = 10.5 mA\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eTest Result:\u003c\/strong\u003e VERY STRONG\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv\u003e\u003cstrong\u003eValve #23:\u003c\/strong\u003e\u003c\/div\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003eSection 1: Gm = 2100 ; Ia = 9.6 mA\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eSection 2: Gm = 1900 ; Ia = 8.2 mA\u003c\/span\u003e\u003cspan\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv\u003e\u003cstrong\u003eValve #27:\u003c\/strong\u003e\u003c\/div\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003eSection 1: Gm = 2100 ; Ia = 9.6 mA\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eSection 2: Gm = 1900 ; Ia = 9.0 mA\u003c\/span\u003e\u003cspan\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv\u003e\u003cstrong\u003eValve #31:\u003c\/strong\u003e\u003c\/div\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003eSection 1: Gm = 2160 ; Ia = 10.4 mA\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eSection 2: Gm = 1860 ; Ia = 9.0 mA\u003c\/span\u003e\u003cspan\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv\u003e\u003cstrong\u003eValve #34:\u003c\/strong\u003e\u003c\/div\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003eSection 1: Gm = 2000 ; Ia = 9.4 mA\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eSection 2: Gm = 2050 ; Ia = 10.2 mA\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv\u003e\u003cstrong\u003eAdditional Tests Performed:\u003c\/strong\u003e\u003c\/div\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cstrong\u003eMicrophonics:\u003c\/strong\u003e Standard. Tested and approved for use in hi-fi and guitar amplifiers. Recommended for use in V2, V3, V4, as a driver, or in less critical stages. Not recommended in V1 or in very high-gain positions that are particularly sensitive to microphonics.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eBalance:\u003c\/strong\u003e The sections present a coherent overall balance, fully compatible with use in hi-fi and musical amplifiers, in all applications where absolute symmetry between the sections is not required.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eOutput Quality:\u003c\/strong\u003e Excellent – Very strong and stable output, no fluctuations.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eShort circuits and GAS:\u003c\/strong\u003e Absent.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003cp\u003e\u003cstrong\u003eConditions:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cstrong\u003eCondition:\u003c\/strong\u003e Vintage - Tested and working - Comes in our custom box for optimal protection.\u003cbr\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eFunctionality:\u003c\/strong\u003e Fully functional.\u003cbr\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eCosmetic condition:\u003c\/strong\u003e Good – Lettering partially eroded, but still legible. Valve body in good condition. See photos for details.\u003cbr\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eManufacturing Code:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e56-30 → RMA\/EIA Open Date Code → manufactured week 30 of 1956\u003cbr\u003e56-52 → RMA\/EIA Open Date Code → manufactured week 52 of 1956\u003c\/li\u003e\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 durability\" rel=\"noopener\" target=\"_blank\"\u003eFind out why our valves are different →\u003c\/a\u003e\u003c\/p\u003e","brand":"RCA","offers":[{"title":"Default Title","offer_id":56409787990364,"sku":"03342","price":164.9,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0616\/3775\/5127\/files\/2_1164d1c5-f0bf-4ae8-9e97-9e9bfbd24c04.jpg?v=1767868081","url":"https:\/\/vacuumtubestreasures.com\/en-hr\/products\/5963-12au7-rca-matched-quad-long-black-plates-foil-getter-amplitrex-tested","provider":"Vacuum Tubes Treasures","version":"1.0","type":"link"}