{"id":4900,"date":"2024-11-24T12:56:01","date_gmt":"2024-11-24T12:56:01","guid":{"rendered":"https:\/\/maffez.com\/?page_id=4900"},"modified":"2025-01-16T17:12:04","modified_gmt":"2025-01-16T17:12:04","slug":"model-5-roland-sh-5-inspired","status":"publish","type":"page","link":"https:\/\/maffez.com\/?page_id=4900","title":{"rendered":"Model 5 (Roland SH-5 inspired)"},"content":{"rendered":"\n<p>This is an easy build and rather simple circuit, based on the Roland SH-5 BPF. There are a number of bandpass filters for Euro inspired by the Roland, yet I didn&#8217;t find any DIY versions that have CV over cutoff frequency.  So, I simply took the original schematic and replaced the dual gang cutoff pot with a dual OTA and CV control. While I was at it, I also tapped the High Pass and Low Pass frequency responses that are unused in the old Roland monolith (or any of the BPF clones, for that matter).<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"446\" height=\"1024\" src=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517927-446x1024.jpg\" alt=\"\" class=\"wp-image-4902\" style=\"width:345px;height:auto\" srcset=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517927-446x1024.jpg 446w, https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517927-131x300.jpg 131w, https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517927-768x1764.jpg 768w, https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517927-669x1536.jpg 669w, https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517927-891x2048.jpg 891w, https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517927.jpg 958w\" sizes=\"auto, (max-width: 446px) 100vw, 446px\" \/><\/figure>\n<\/div>\n\n\n<p>That&#8217;s what it looks like. Improvement in the version linked below is that the lettering is on the silkscreen layer, i.e. brighter (white) and better readable.<\/p>\n\n\n\n<p>A couple of sounds:<\/p>\n\n\n\n<figure class=\"wp-block-audio\"><audio controls src=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/Model5_modes_d.mp3\"><\/audio><\/figure>\n\n\n\n<p>Low Pass<\/p>\n\n\n\n<figure class=\"wp-block-audio\"><audio controls src=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/lopass.mp3\"><\/audio><\/figure>\n\n\n\n<p>Band Pass<\/p>\n\n\n\n<figure class=\"wp-block-audio\"><audio controls src=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/bandpass.mp3\"><\/audio><\/figure>\n\n\n\n<p>High Pass<\/p>\n\n\n\n<figure class=\"wp-block-audio\"><audio controls src=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/hipass.mp3\"><\/audio><\/figure>\n\n\n\n<p>Dual Bandpass (two Model 5 in series, one with inverted modulation)<\/p>\n\n\n\n<figure class=\"wp-block-audio\"><audio controls src=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/dual_model5.mp3\"><\/audio><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Circuit Description<\/strong><\/h2>\n\n\n\n<p>As you can hear, the filter sound stays mostly sweet in contrast to, say the &#8220;can sound beeped up&#8221; vibe of the Oberheim SEM. You can push the Model 5 in the latter direction easily, though, if you want to. Simply decrease the input attenuation (replace the 22k resistor R2 with 100k). This is how the &#8220;stock&#8221; version as per schematic sounds (3340-based VCO going full tilt into the filter): <\/p>\n\n\n\n<figure class=\"wp-block-audio\"><audio controls src=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/lp_bp_hp_saw.mp3\"><\/audio><\/figure>\n\n\n\n<p>Another characteristic of the original design is that the maximum cutoff frequency is relatively low at (around 6.5 Kilohertz), which I kept in this module too.<\/p>\n\n\n\n<p>As for the rest, the thing does what it says on the tin.  Input with level control, unipolar modulation input, manual resonance control, buffered outputs for low, band, and high pass.   <\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"710\" height=\"1024\" src=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517894-710x1024.jpg\" alt=\"\" class=\"wp-image-4901\" style=\"width:276px;height:auto\" srcset=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517894-710x1024.jpg 710w, https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517894-208x300.jpg 208w, https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517894-768x1108.jpg 768w, https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517894-1064x1536.jpg 1064w, https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/1732451517894.jpg 1153w\" sizes=\"auto, (max-width: 710px) 100vw, 710px\" \/><\/figure>\n<\/div>\n\n\n<h2 class=\"wp-block-heading\"><strong>Build<\/strong> <strong>and Production Files<\/strong><\/h2>\n\n\n\n<p>There is nothing really complicated here, really. A LM13700, two quad op amps, and a dual op amp. For the 22n capacitors at the filter core, I use Panasonic ECHUX 22N 16, which sound great and fit the footprint well. All resistors are 0805, and no special parts are needed.  <\/p>\n\n\n\n<p>Here&#8217;s the schematic<\/p>\n\n\n\n<div data-wp-interactive=\"core\/file\" class=\"wp-block-file\"><object data-wp-bind--hidden=\"!state.hasPdfPreview\" hidden class=\"wp-block-file__embed\" data=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/Model5_Schematic1_1.pdf\" type=\"application\/pdf\" style=\"width:100%;height:600px\" aria-label=\"Embed of Model5_Schematic1_1.\"><\/object><a id=\"wp-block-file--media-b3397e0f-b115-4614-b301-e8fe686d275e\" href=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/Model5_Schematic1_1.pdf\">Model5_Schematic1_1<\/a><a href=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/Model5_Schematic1_1.pdf\" class=\"wp-block-file__button wp-element-button\" download aria-describedby=\"wp-block-file--media-b3397e0f-b115-4614-b301-e8fe686d275e\">Download<\/a><\/div>\n\n\n\n<p><\/p>\n\n\n\n<p>And here are the Gerbers (Panel, and main PCB), BOM, and what have you.<\/p>\n\n\n\n<div class=\"wp-block-file\"><a id=\"wp-block-file--media-6be2422b-c3a7-4712-901b-a7757dad9e71\" href=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/GERBERS_BOM_MODEL5.zip\">GERBERS_BOM_MODEL5<\/a><a href=\"https:\/\/maffez.com\/wp-content\/uploads\/2024\/11\/GERBERS_BOM_MODEL5.zip\" class=\"wp-block-file__button wp-element-button\" download aria-describedby=\"wp-block-file--media-6be2422b-c3a7-4712-901b-a7757dad9e71\">Download<\/a><\/div>\n\n\n\n<p><\/p>\n\n\n\n<p>And here&#8217;s a strip board version, someone kindly sent to me:<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"732\" src=\"https:\/\/maffez.com\/wp-content\/uploads\/2025\/01\/Model5Stripboardversion_maik-1-1024x732.png\" alt=\"\" class=\"wp-image-5018\" srcset=\"https:\/\/maffez.com\/wp-content\/uploads\/2025\/01\/Model5Stripboardversion_maik-1-1024x732.png 1024w, https:\/\/maffez.com\/wp-content\/uploads\/2025\/01\/Model5Stripboardversion_maik-1-300x215.png 300w\" sizes=\"auto, (max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><\/figure>\n<\/div>\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>This is an easy build and rather simple circuit, based on the Roland SH-5 BPF. There are a number of bandpass filters for Euro inspired by the Roland, yet I didn&#8217;t find any DIY versions that have CV over cutoff frequency. So, I simply took the original schematic and replaced the dual gang cutoff pot &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/maffez.com\/?page_id=4900\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Model 5 (Roland SH-5 inspired)&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-4900","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/maffez.com\/index.php?rest_route=\/wp\/v2\/pages\/4900","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/maffez.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/maffez.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/maffez.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/maffez.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4900"}],"version-history":[{"count":4,"href":"https:\/\/maffez.com\/index.php?rest_route=\/wp\/v2\/pages\/4900\/revisions"}],"predecessor-version":[{"id":5020,"href":"https:\/\/maffez.com\/index.php?rest_route=\/wp\/v2\/pages\/4900\/revisions\/5020"}],"wp:attachment":[{"href":"https:\/\/maffez.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4900"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}