{"id":4373,"date":"2015-02-01T13:45:43","date_gmt":"2015-02-01T13:45:43","guid":{"rendered":"http:\/\/www.bartola.co.uk\/valves\/?p=4373"},"modified":"2015-02-01T13:45:43","modified_gmt":"2015-02-01T13:45:43","slug":"4p1l-siberian-gen1-upgrade","status":"publish","type":"post","link":"https:\/\/www.bartola.co.uk\/valves\/2015\/02\/01\/4p1l-siberian-gen1-upgrade\/","title":{"rendered":"4P1L Siberian Gen1 upgrade"},"content":{"rendered":"

Some of the DIYAudio fans have built this<\/a> version of the 4P1L with great success. There are several upgrades that can be easily implemented to improve this. I haven’t tried this myself, but my recent experience with the Gen3<\/a> and the 01 preamp gen2<\/a>, I think are worth trying:<\/p>\n

    \n
  1. Replace the gyrator FET for a cascoded pair (M2 and M4 below) to improve PSR<\/li>\n
  2. Replace voltage reference by a cascoded LND150 for better HF and PSR response<\/li>\n
  3. Optimise the LF pole of the gyrator load by increasing R4 to 4.7 M\u03a9 and reduce C1 to 220nF<\/li>\n
  4. Bias 4P1L to about 30mA. This will reduce distortion<\/li>\n<\/ol>\n

    Hope this is useful<\/p>\n

    Ale<\/p>\n

    \"4P1L<\/a> \"4P1L<\/a><\/p>\n

     <\/p>\n","protected":false},"excerpt":{"rendered":"

    Some of the DIYAudio fans have built this version of the 4P1L with great success. There are several upgrades that can be easily implemented to improve this. I haven’t tried this myself, but my recent experience with the Gen3 and the 01 preamp gen2, I think are worth trying: Replace the gyrator FET for a … Continue reading “4P1L Siberian Gen1 upgrade”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[12,156,67],"tags":[782,537,703,112,21,186,47,72,44,78,702,584],"class_list":["post-4373","post","type-post","status-publish","format-standard","hentry","category-dht-valves","category-pre-amplifier-valves","category-thd","tag-4p1l","tag-4p1l-dht","tag-4p1l-dht-line-stage","tag-4p1l-dht-pre-amp","tag-dht-pre-amplifier","tag-dht-preamp","tag-dht-preamplifier","tag-dn2540","tag-gyrator","tag-rod-coleman-regulator","tag-siberian-pre-amplifier","tag-siberian-preamp"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2r2tK-18x","jetpack_likes_enabled":true,"jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/4373","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/comments?post=4373"}],"version-history":[{"count":1,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/4373\/revisions"}],"predecessor-version":[{"id":4376,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/4373\/revisions\/4376"}],"wp:attachment":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/media?parent=4373"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/categories?post=4373"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/tags?post=4373"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}