{"id":839,"date":"2012-02-20T13:09:13","date_gmt":"2012-02-20T18:09:13","guid":{"rendered":"http:\/\/abrammorphew.com\/notes\/?p=839"},"modified":"2012-03-05T17:28:33","modified_gmt":"2012-03-05T22:28:33","slug":"mellotronium-revised","status":"publish","type":"post","link":"http:\/\/abrammorphew.com\/notes\/2012\/02\/20\/mellotronium-revised\/","title":{"rendered":"Mellotronium revised&#8230;"},"content":{"rendered":"<p><iframe loading=\"lazy\" src=\"http:\/\/player.vimeo.com\/video\/37086321\" width=\"500\" height=\"375\" frameborder=\"0\" webkitAllowFullScreen mozallowfullscreen allowFullScreen><\/iframe><\/p>\n<p>here&#8217;s an update on the new additions\/approach to the Mellotronium. i&#8217;m attempting to redo the SD card routines once i get the functionality added. using the SD library just doesn&#8217;t work right when reading byte values at 8kHz. i&#8217;ve looked into the WaveHC library with the most success, but had to modify not to use an external DAC. a new wav file playing solution from the SD card will have to be found.  <\/p>\n<p>without the clunky SD lib, program space has opened up&#8230; a lot of it in fact. now i&#8217;ve started using a wavetable. this video just has a single sine wave, but it&#8217;s modulate with the LFO and its seven different waveforms not to mention an amplitude modulating ADSR filter. <\/p>\n<p>the breadboard to the side contains an experimental active 2-band EQ (TLO82-based) which needs some work. if anyone has any experience with this, i would love to know why the schematic in the datasheet doesn&#8217;t work at all. i wound up having to recall the usage from a different schematic where you make a voltage divider from and peer it into the positive terminal on both opamps. it works&#8230; in a way. i think i&#8217;ve inverted the wave form or something strange. it also sometimes works better as a radio than an EQ which i think i like. it made for some interesting heterodyning.  <\/p>\n","protected":false},"excerpt":{"rendered":"<p>here&#8217;s an update on the new additions\/approach to the Mellotronium. i&#8217;m attempting to redo the SD card routines once i get the functionality added. using the SD library just doesn&#8217;t work right when reading byte values at 8kHz. i&#8217;ve looked into the WaveHC library with the most success, but had to modify not to use [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[129,102,103,25,108,130,110,109,104,106,105,127,131],"class_list":["post-839","post","type-post","status-publish","format-standard","hentry","category-notes","tag-2-band","tag-arduino","tag-atmega328","tag-audio","tag-digital","tag-eq","tag-mellotron","tag-mellotronium","tag-optiboot","tag-pcm","tag-pwm","tag-synth","tag-tl082"],"_links":{"self":[{"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/posts\/839","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/comments?post=839"}],"version-history":[{"count":2,"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/posts\/839\/revisions"}],"predecessor-version":[{"id":854,"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/posts\/839\/revisions\/854"}],"wp:attachment":[{"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/media?parent=839"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/categories?post=839"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/abrammorphew.com\/notes\/wp-json\/wp\/v2\/tags?post=839"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}