{"id":8057,"date":"2019-10-25T22:51:07","date_gmt":"2019-10-25T21:51:07","guid":{"rendered":"https:\/\/www.bartola.co.uk\/valves\/?p=8057"},"modified":"2019-10-25T22:51:08","modified_gmt":"2019-10-25T21:51:08","slug":"hp-experiments-part-1","status":"publish","type":"post","link":"https:\/\/www.bartola.co.uk\/valves\/2019\/10\/25\/hp-experiments-part-1\/","title":{"rendered":"HP experiments &#8211; part 1"},"content":{"rendered":"<p>Experimenting on headphone amplifiers, not always turn out the way you expected. Well, that&#8217;s the nature of experimentation and some smoke may come along the way.<\/p>\n<p>Here is my new take on the headphone amp. Modified the 2P29L to fit the 6e6p-dr valve. I love this IHT one, so wanted to experiment more.<\/p>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"8059\" data-permalink=\"https:\/\/www.bartola.co.uk\/valves\/2019\/10\/25\/hp-experiments-part-1\/img_0756\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?fit=3725%2C2793&amp;ssl=1\" data-orig-size=\"3725,2793\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;1.8&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;iPhone 8&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;1572038550&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;3.99&quot;,&quot;iso&quot;:&quot;40&quot;,&quot;shutter_speed&quot;:&quot;0.033333333333333&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"img_0756\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?fit=840%2C630&amp;ssl=1\" src=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?resize=840%2C630&#038;ssl=1\" class=\"aligncenter size-full wp-image-8059\" width=\"840\" height=\"630\" srcset=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?w=3725&amp;ssl=1 3725w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?resize=300%2C225&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?resize=768%2C576&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?resize=1024%2C768&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?resize=1200%2C900&amp;ssl=1 1200w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?w=1680&amp;ssl=1 1680w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2019\/10\/img_0756.jpg?w=2520&amp;ssl=1 2520w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 1362px) 62vw, 840px\" \/>Instead of the classic HT, I used some Chinese 300-450V SMPS modules. I used the 70W version with success before, not these tiny ones.<\/p>\n<p>Individually tested all parts and worked fine. Fired up the SMPS with the hot filaments and the 6e6p-dr running at 20mA each and the SMPS oscillated. They went to 450V instead of the 250V dialled and one of my cap multiplier PCB boards got damaged. Damn!<\/p>\n<p>Back to the drawing board. I will probably stick to the simple HT supply \ud83d\ude42<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Experimenting on headphone amplifiers, not always turn out the way you expected. Well, that&#8217;s the nature of experimentation and some smoke may come along the way. Here is my new take on the headphone amp. Modified the 2P29L to fit the 6e6p-dr valve. I love this IHT one, so wanted to experiment more. Instead of &hellip; <a href=\"https:\/\/www.bartola.co.uk\/valves\/2019\/10\/25\/hp-experiments-part-1\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;HP experiments &#8211; part 1&#8221;<\/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":[5],"tags":[606,625,1235,44,31,1231,1232,652,1233,1234],"class_list":["post-8057","post","type-post","status-publish","format-standard","hentry","category-valves","tag-6e6p","tag-bartola","tag-dt-770-pro","tag-gyrator","tag-headphone-amplifier","tag-headphones","tag-hp","tag-hybrid-mu-follower","tag-mundorf-oil-caps","tag-sennheiser-hd650"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2r2tK-25X","jetpack_likes_enabled":true,"jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/8057","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=8057"}],"version-history":[{"count":1,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/8057\/revisions"}],"predecessor-version":[{"id":8060,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/8057\/revisions\/8060"}],"wp:attachment":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/media?parent=8057"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/categories?post=8057"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/tags?post=8057"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}