{"product_id":"matched-balanced-philco-6sn7gtb-tubes-black-angle-plates-57-52-56-13-6sn7gt","title":"Matched \u0026 Balanced Philco 6SN7GTB Tubes Black Angle Plates 57-52 56-13 6SN7GT","description":"\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003eTested \u003cb\u003eMatched and Balanced\u003c\/b\u003e Pair of Philco 6SN7GTB Tubes.\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003eDate Codes 57-52 and 56-13.\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003eThe 312 EIA codes indicates that these tubes were made by \u003ci\u003eSylvania\u003c\/i\u003e for Philco.\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003eTubes are matched for Gm testing (see below) and internal structure - they are identical.\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cspan\u003e\u003cb\u003ePerfectly \u003c\/b\u003e\u003c\/span\u003e\u003cspan\u003e\u003cb\u003ematched and balanced\u003c\/b\u003e\u003c\/span\u003e\u003cspan\u003e set with black angled T plates and clear mica spacers.\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cspan\u003eTested on a calibrated Hickok TV-10 military tube tester\u003c\/span\u003e\u003cb\u003e\u003c\/b\u003e\u003cspan\u003e with \u003c\/span\u003e\u003cb\u003eno shorts\u003c\/b\u003e\u003cspan\u003e and \u003c\/span\u003e\u003cb\u003eno leaks\u003c\/b\u003e\u003cspan\u003e with the following results:\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\n\u003cdiv\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003eGm Test = 2625-2625 and 2625-2625 micromhos\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cspan\u003eMinimum pass\/good = \u003c\/span\u003e\u003cspan\u003e1650-1650\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cspan\u003eFurther tested under real operating conditions on a Class A amplifier and exhibiting \u003c\/span\u003e\u003cb\u003eno microphonics\u003c\/b\u003e\u003cspan\u003e.\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cb\u003e~ Please view all 5 photos ~\u003c\/b\u003e\u003c\/div\u003e","brand":"Classic Currents","offers":[{"title":"Default Title","offer_id":47742390698239,"sku":null,"price":74.95,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0788\/5999\/3343\/files\/s-l1600-16_4ad5d1e1-8912-4f82-9f9c-e98acdb4745f.webp?v=1765433304","url":"https:\/\/classiccurrents.com\/products\/matched-balanced-philco-6sn7gtb-tubes-black-angle-plates-57-52-56-13-6sn7gt","provider":"Classic Currents","version":"1.0","type":"link"}