{"id":155544,"date":"2023-02-21T23:20:10","date_gmt":"2023-02-21T23:20:10","guid":{"rendered":"https:\/\/www.techweekmag.com\/?p=155544"},"modified":"2023-10-18T06:10:55","modified_gmt":"2023-10-18T05:10:55","slug":"western-electric-91e-integrated-stereo-amplifier-on-modern-triodes-300v","status":"publish","type":"post","link":"https:\/\/www.stereoindex.com\/tech\/hi-fi\/western-electric-91e-integrated-stereo-amplifier-on-modern-triodes-300v\/","title":{"rendered":"Western Electric 91E: Integrated stereo amplifier on modern triodes 300V"},"content":{"rendered":"<p>Western Electric is taking orders for the 91E single-ended (SE) integrated amplifier, inspired by the iconic 91A.<\/p>\n<p>In the distant past, the 91A was used in early Hollywood films.\u00a0After resuming production of 300B triode tubes at its state-of-the-art Rossville Works, Western Electric is now launching a new SE delivering over 20W per channel &#8211; a first for a 300B in a 21st century design.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-155545\" src=\"https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/Pasted-37.jpg\" alt=\"\" width=\"800\" height=\"445\" srcset=\"https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/Pasted-37.jpg 800w, https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/Pasted-37-770x428.jpg 770w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><\/p>\n<p>Western Electric Type 91E is built with a patented circuit that more than doubles the power of the 300B compared to conventional 7-8W.\u00a0The amplifier received a replaceable transformer block &#8211; the standard 8 ohm transformer block can be replaced with an optional 4 ohm version.\u00a0A matched pair of 300Bs, included with each amplifier, are front and center mounted.\u00a0The microprocessors automatically adjust the bias current of the 300V pair each time the amplifier is turned on.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-9475\" src=\"https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/191_techweek.jpg\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" srcset=\"https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/191_techweek.jpg 1024w, https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/193_techweek.jpg 390w, https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/194_techweek.jpg 768w\" alt=\"\" width=\"1024\" height=\"445\" \/><\/p>\n<p>The 91E uses a parallel power topology that sends half the AC current to the 300B plate (anode), modulating the quiescent current.\u00a0As a result, half of the power dissipated occurs in the lamp, resulting in more power output.\u00a0A stepped logarithmic attenuator is used to simulate the response of human hearing.\u00a0It is assembled from discrete resistors in a ladder configuration, providing logarithmic output attenuation.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-9474\" src=\"https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/192_techweek.jpg\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" srcset=\"https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/192_techweek.jpg 1024w, https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/195_techweek.jpg 364w, https:\/\/www.stereoindex.com\/tech\/wp-content\/uploads\/2023\/02\/196_techweek.jpg 768w\" alt=\"\" width=\"1024\" height=\"576\" \/><\/p>\n<p>The dimmable color LCD displays the selected input, attenuator level and volume meter.\u00a0The display also shows settings that can be adjusted using the supplied remote control.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Western Electric is taking orders for the 91E single-ended (SE) integrated amplifier, inspired by the iconic 91A. In the distant past, the 91A was used in early Hollywood films.\u00a0After resuming production of 300B triode tubes at its state-of-the-art Rossville Works, Western Electric is now launching a new SE delivering over 20W per channel &#8211; a [&hellip;] <a class=\"g1-link g1-link-more\" href=\"https:\/\/www.stereoindex.com\/tech\/hi-fi\/western-electric-91e-integrated-stereo-amplifier-on-modern-triodes-300v\/\">More<\/a><\/p>\n","protected":false},"author":1,"featured_media":155546,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[642],"tags":[779],"class_list":{"0":"post-155544","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-hi-fi","8":"tag-news"},"acf":[],"aioseo_notices":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/posts\/155544","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/comments?post=155544"}],"version-history":[{"count":0,"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/posts\/155544\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/media\/155546"}],"wp:attachment":[{"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/media?parent=155544"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/categories?post=155544"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.stereoindex.com\/tech\/wp-json\/wp\/v2\/tags?post=155544"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}