{"product_id":"ecc88-6dj8-sylvania-amplitrex-matched-pair-halo-getter-tubes-made-in-usa","title":"ECC88 \/ 6DJ8 SYLVANIA AMPLITREX Matched Pair Halo Getter Tubes Made in USA","description":"\u003ch3\u003e\u003cstrong\u003eECC88 \/ 6DJ8 SYLVANIA Halo Getter Tested Tubes Made in USA '60s\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eAMPLITREX Matched Pair – Low Noise \u0026amp; Microphonics – Vintage American SYLVANIA Production\u003c\/strong\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eTest Results\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eTested on \u003cstrong\u003eAMPLITREX AT-1000\u003c\/strong\u003e Tube Tester\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eVoltage Test:\u003cspan\u003e \u003c\/span\u003e\u003c\/strong\u003e Va = 90V ; Vg = -1.2V\u003cstrong\u003e\u003cbr\u003eAverage 100%:\u003c\/strong\u003e Gm = 12.5 ; Ia = 15.0 mA\u003cstrong\u003e\u003cbr\u003eTEST RESULT:\u003c\/strong\u003e VERY STRONG\u003c\/p\u003e\n\u003cp class=\"p1\"\u003e\u003cstrong\u003eTube #3:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003eSection 1: Gm = 11.70 ; Ia = 12.8 mA\u003c\/li\u003e\n\n\u003cli\u003eSection 2: Gm = 11.90 ; Ia = 14.3 mA\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp class=\"p1\"\u003e\u003cstrong\u003eTube #5:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003eSection 1: Gm = 11.64 ; Ia = 13.8 mA\u003c\/li\u003e\n\n\u003cli\u003eSection 2: Gm = 11.20 ; Ia = 13.2 mA\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cdiv\u003e\n\n\u003cstrong style=\"font-family: -apple-system, BlinkMacSystemFont, 'San Francisco', 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif; font-size: 0.875rem;\"\u003eAdditional Tests performed:\u003c\/strong\u003e\u003cstrong\u003e\u003c\/strong\u003e\n\n\u003c\/div\u003e\n\u003cdiv\u003e\n\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-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 Absent.\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\u003eAn interesting pair of \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eAmerican-made ECC88 \/ 6DJ8 Sylvania tubes\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, dating approximately to the 1960s and featuring the classic \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eHalo Getter\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e construction. Although they lack original silk-screening, the structural characteristics are consistent with Sylvania production of the era, appreciated for its solidity, reliability, and quality performance in high-sensitivity audio circuits.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe two tubes form a particularly homogeneous \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eAmplitrex Matched\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e pair. Tube #3 has an average transconductance of \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e11.80 mA\/V\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, while Tube #5 reaches \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e11.42 mA\/V\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, with a difference limited to around \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e3%\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. Even more significant is the correspondence of the average anode currents: \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e13.55 mA and 13.50 mA\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, values that are practically identical and confirm the excellent operational uniformity of the pair.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe internal balance is also \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003every good\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e: all sections show consistent and well-distributed values, with stable behavior verified through \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e48 hours of burn-in\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. No fluctuations, gas, or short circuits emerged during testing.\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, combined with good electrical uniformity, makes this pair particularly suitable for hi-fi preamplifiers, headphone amplifiers, buffers, line stages, drivers, and professional equipment compatible with ECC88 or 6DJ8. The careful selection allows their use even in the most sensitive audio stages and in applications where maintaining good consistency between the two channels is important.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eIn terms of sound, the American Sylvania ECC88s are appreciated for an \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eopen, dynamic, and natural\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e presentation, with a defined midrange, fast and controlled low frequencies, and an airy top end without excessive harshness. In hi-fi systems, they promote transparency, image precision, and well-articulated reproduction; in musical instrument amplifiers, they offer a snappy response, clarity, and good transient control.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eA very interesting offer for those seeking an \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eelectrically well-matched vintage American pair\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, with Halo Getter, low microphonics, exceptionally close anode currents, and stable parameters: two authentic Sylvania Made in USA tubes, individually tested and ready for use.\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 Vintage Tubes - Tested and perfectly 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\u003cspan\u003e Fair – Markings completely gone. 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 Indecipherable code. Production attributable approximately to the 1960s based on structural characteristics.\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003e\u003ca rel=\"noopener\" title=\"Why our tubes are different – the VTT protocol that improves sound, reliability, and lifespan\" 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\u003cmeta charset=\"utf-8\"\u003e\u003c\/p\u003e","brand":"SYLVANIA","offers":[{"title":"Default Title","offer_id":59339143643484,"sku":"03863L","price":148.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0616\/3775\/5127\/files\/8_4f51fb83-b7f7-4f85-b2f1-735e45724d8b.jpg?v=1790954623","url":"https:\/\/vacuumtubestreasures.com\/en-ca\/products\/ecc88-6dj8-sylvania-amplitrex-matched-pair-halo-getter-tubes-made-in-usa","provider":"Vacuum Tubes Treasures","version":"1.0","type":"link"}