{"title":"PCB - Power Amplifier","description":"","products":[{"product_id":"amp-camp-amp-pcb","title":"Amp Camp Amp PCB","description":"\u003cdiv\u003eThese are the current revision of the Amp Camp Amp PCB. The ACA V1.8 kit uses these PCBs.\u003cbr\u003e\n\u003c\/div\u003e\n\u003cdiv\u003eThese are available with either:\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cul\u003e\n\u003cli\u003eTinned copper traces\u003c\/li\u003e\n\u003cli\u003eGold plated copper traces\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv\u003eThe official ACA kits have used either over the years, and experts would tell you the trace material makes no difference at all to the sound. Choose what feels right to you.\u003cbr\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003ctable id=\"product-attribute-specs-table\" class=\"data-table\"\u003e\n\u003ctbody\u003e\n\u003ctr class=\"even\"\u003e\n\u003cth class=\"label\"\u003eDimensions\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e88mm x 57mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"odd\"\u003e\n\u003cth class=\"label\"\u003eMounting holes\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e\n\u003ca href=\"\/pages\/universal-mounting-specification-v3\"\u003eUMS Heatsink\u003c\/a\u003e Compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eLayers\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eBoard Revision\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e1.6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eBoard Color\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003eGreen\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eTracks\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e35um copper\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e","brand":"diyAudio Store","offers":[{"title":"Tin traces","offer_id":16373247213602,"sku":"DIYP-ACA-216","price":10.0,"currency_code":"USD","in_stock":true},{"title":"Gold traces","offer_id":5938996356,"sku":"DIYP-ACAG-216","price":15.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/IMG_3551.png?v=1715643423"},{"product_id":"aleph-j","title":"Aleph J Circuit Boards","description":"","brand":"diyAudio Store","offers":[{"title":"Default Title","offer_id":5941228356,"sku":"DIYP-AJ-220","price":25.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/AJCircuitBoards.png?v=1716431455"},{"product_id":"f-5t","title":"F5 Turbo PCBs","description":"\u003cp\u003eThis set of circuit boards is used to make the F5 Turbo power amplifier from the mind of DIY hero and audio genius, Nelson Pass.\u003c\/p\u003e\n\u003cp\u003eOne set of PCBs will make a stereo F5 Turbo v2, or a single monoblock F-5T v3.  This is the third revision of the boards, which has nothing to do with using them to make a V2 or V3 F5 Turbo!\u003c\/p\u003e\n\u003cp\u003ePlease read the \u003ca href=\"https:\/\/www.firstwatt.com\/wp-content\/uploads\/2024\/01\/art_f5_turbo.pdf\"\u003eF5 Turbo Article\u003c\/a\u003e written by Mr. Pass to familiarize yourself with the different versions.\u003c\/p\u003e\n\u003ch4\u003eIllustrated build guide\u003c\/h4\u003e\n\u003cp\u003eAn Illustrated build guide showing all sorts of useful information on how to build your F5Turbo can be found here - \u003ca href=\"http:\/\/www.diyaudio.com\/forums\/pass-labs\/254056-f5turbo-illustrated-build-guide.html\"\u003eIllustrated Build Guide\u003c\/a\u003e\u003c\/p\u003e\n\u003ch4\u003eCircuit Description\u003c\/h4\u003e\n\u003cp\u003eThe F5 Turbo is a Push-Pull, Class-A power amplifier. Esentally a scaled-up F5, with more output devices and a higher voltage power supply. The F-5 Turbo is a voltage source amplifier, requiring nothing out of the ordinary from your preamp or speakers.\u003c\/p\u003e\n\u003cp\u003eThe F5 Turbo is the biggest offering in the Nelson Pass\/Firstwatt DIY series of amplifiers. The v3 will handily drive 100Watts into 8ohm, and much more into 4ohm. This circuit also has the ability to scale up to truly amazing power levels.\u003c\/p\u003e\n\u003cp\u003ePopulate these boards with your components, then add your own power supply, chassis and heat sinks to complete the amplifier. The mounting hole spacing is compatible with the \u003ca href=\"\/pages\/universal-mounting-specification\"\u003ediyAudio Universal Mounting Specification\u003c\/a\u003e mounting pattern found in the Deluxe Chassis.\u003c\/p\u003e\n\u003ch4\u003eOutput Power\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eF5T v2 - 50 Watts per channel into 8ohm\u003c\/li\u003e\n\u003cli\u003eF5T v3 - 100 Watts into 8ohm. (The v3 should be built as monoblocks.)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003ePower supply requirements\u003c\/h4\u003e\n\u003cp\u003eA stereo F5 Turbo v2 requires a bipolar power supply of (+\/- 32V). This will require an 24V+24V (or 48V Center Tapped) transformer from 600-800VA, and PSU capacitance of 80,000uF per rail or more. The DIYaudio \u003ca href=\"\/collections\/power-supplies-accessories\/products\/universal-psu\"\u003eUniversal PSU v3\u003c\/a\u003e was made with the requirments of this very amp when it was designed.\u003c\/p\u003e\n\u003cp\u003eThe F5 Turbo v3 will require two of the above PSU. (One for each monoblock)\u003c\/p\u003e\n\u003cp\u003eThe amplifier has the ability to use a higher voltage PSU for more power, but you must 'cascode' the driver stage of the amp to protect the input JFETs. (And have even more heatsink.) See the article for more details.\u003c\/p\u003e\n\u003ch4\u003eChassis suggestions\u003c\/h4\u003e\n\u003cp\u003eThis is a high-wattage Class-A amplifier. It has lots of excess heat that needs to be dealt with. The 5U Chassis is of suitable size and dissipation for a Stereo v2 or a mono v3.\u003c\/p\u003e\n\u003cp\u003eThe \u003ca href=\"https:\/\/diyaudiostore.com\/products\/2025-deluxe-chassis-5u\"\u003e5U Deluxe amplifier chassis\u003c\/a\u003e makes a great home for the F5 Turbo. The \u003ca href=\"\/pages\/universal-mounting-specification\"\u003ediyAudio \"Universal Mounting Specification\" (UMS)\u003c\/a\u003e is a common mounting pattern between the amplifier PCB and the heatsinks. The driver board will fit on the heatsinks, between the output boards.\u003c\/p\u003e\n\u003ch2\u003eHelpful Links\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca rel=\"noopener\" href=\"https:\/\/www.firstwatt.com\/wp-content\/uploads\/2023\/12\/art_f5_turbo.pdf\" target=\"_blank\"\u003eF5 Turbo Article by Nelson Pass\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"http:\/\/www.diyaudio.com\/forums\/attachments\/pass-labs\/374352d1380703296-f5-turbo-builders-thread-f5-turbo-bom-v2.pdf\"\u003eF5T v2 Bill of Materials\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"http:\/\/www.diyaudio.com\/forums\/attachments\/pass-labs\/374706d1380891005-f5-turbo-builders-thread-f5-turbo-v3-bomrev2.pdf\"\u003eF5T v3 Bill of Materials\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"http:\/\/www.diyaudio.com\/forums\/diyaudio-store\/233915-f-5t-boards.html\"\u003eSupport discussion thread for these boards\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003ePlease note that while these boards are marked as \"V3\" that refers to the fact they are the third revision of the boards. You can use these boards to make either a F5 Turbo v2 or v3.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eOther Notes\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eThe \u003ca href=\"https:\/\/www.firstwatt.com\/wp-content\/uploads\/2024\/01\/art_f5_turbo.pdf\"\u003eF5 Turbo\u003c\/a\u003e, is an \u003ca href=\"https:\/\/diyaudiostore.com\/products\/f-5\"\u003eF5\u003c\/a\u003e on steroids, with outputs up to 100w per channel\u003c\/li\u003e\n\u003cli\u003eFor questions about the PCB itself and myriad links to the original article, discussion threads and build threads, please see the \u003ca href=\"http:\/\/www.diyaudio.com\/forums\/diyaudio-store\/233915-f-5t-boards.html\"\u003eF-5T boards support thread\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli\u003eThis is not a beginners project\u003c\/li\u003e\n\u003cli\u003eThese boards are the newest revision, having a new layout of the Front-End board featuring many new solder pads, and rationalized labeling and numbering across all the PCBs. The layout has been only slightly modified, but it is different from the v2 PCB.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ctable id=\"product-attribute-specs-table\" class=\"data-table\"\u003e\n\u003ctbody\u003e\n\u003ctr class=\"odd\"\u003e\n\u003cth class=\"label\"\u003eMounting holes\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e\n\u003ca href=\"\/pages\/universal-mounting-specification\"\u003eUMS Heatsink\u003c\/a\u003e Compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eLayers\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eBoard Revision\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e3.0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e","brand":"diyAudio Store","offers":[{"title":"Default Title","offer_id":5941365700,"sku":"DIYP-F5T-630","price":49.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/products\/DSC_0524.png?v=1715882962"},{"product_id":"f-5","title":"F5","description":"\u003ctable id=\"product-attribute-specs-table\" class=\"data-table\"\u003e\n\u003ctbody\u003e\n\u003ctr class=\"even\"\u003e\n\u003cth class=\"label\"\u003eDimensions\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e170mm x 50mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"odd\"\u003e\n\u003cth class=\"label\"\u003eMounting holes\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e\n\u003ca href=\"\/pages\/universal-mounting-specification\"\u003eUMS Heatsink\u003c\/a\u003e Compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eBoard Revision\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e3.0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"diyAudio Store","offers":[{"title":"Default Title","offer_id":5941421764,"sku":"DIYP-F5-230","price":25.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/products\/DSC_0459.png?v=1448506065"},{"product_id":"f-4","title":"F4","description":"\u003ctable id=\"product-attribute-specs-table\" class=\"data-table\"\u003e\n\u003ctbody\u003e\n\u003ctr class=\"even\"\u003e\n\u003cth class=\"label\"\u003eDimensions\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e250mm x 50mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"odd\"\u003e\n\u003cth class=\"label\"\u003eMounting holes\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e\n\u003ca href=\"\/pages\/universal-mounting-specification\"\u003eUMS Heatsink\u003c\/a\u003e Compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eLayers\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eBoard Revision\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e2.0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e","brand":"diyAudio Store","offers":[{"title":"Default Title","offer_id":5941468484,"sku":"DIYP-F4-220","price":25.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/products\/F-4-1.jpg?v=1455101357"},{"product_id":"honey-badger","title":"The \"Honey Badger\"","description":"\u003cp\u003eThe first Class AB power amplifier to be featured at the diyAudio Store. It has been designed from the ground up with the sonic character, power output and most of all the DIYer in mind. With a basic power output of 150W at 8 ohms, this power amp is sure to have a place in every builder’s projects list. Not to mention its flexibility and adaptability to work with most output devices available locally in wherever country you may be.\u003c\/p\u003e\n\u003cp\u003ePlease visit the \u003ca href=\"http:\/\/www.diyaudio.com\/forums\/diyaudio-store\/214002-diyab-honey-badger-class-ab-power-amp-pair.html\"\u003eHoney Badger Helpdesk Thread\u003c\/a\u003e for any questions you might have and for a definitive list of links to all articles and discussions about the amp itself, the build guide, schematics, and Bill of Materials.  The designer OSTripper is active over in the \u003ca href=\"http:\/\/www.diyaudio.com\/forums\/solid-state\/192431-diyab-amp-honey-badger.html\" target=\"_blank\"\u003eHoney Badger General Discussion Thread\u003c\/a\u003e which is where all the action is.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eImportant note on resistor lead size:\u003c\/strong\u003e The resistor lead holes were intentionally made small by the designer. Please check the lead sizes of the parts in the BOM and use them as your maximum lead thickness before purchasing alternate resistors.\u003c\/p\u003e\n\u003ch2\u003eAdditional Information \u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/P-DIYAB-2V20-diyAB-amp-bom.xls\" target=\"_blank\"\u003eBill of Materials\u003c\/a\u003e \u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/2017-01_Honey_Badger_2.4_BOM_by_mbrennwa.pdf?v=1619657882\"\u003eUnofficial 2.4 Bill of Materials by mbrennwa\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/P-DIYAB-2V20-diyAB-amp-schematic.pdf\" target=\"_blank\"\u003eSchematic\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/Annotated_Honey_Badger_2.4_Schematic.pdf?v=1619657915\"\u003eUnofficial 2.4 annotated schematic\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/P-DIYAB-2V20-diyAB-amp-dimensions.pdf\" target=\"_blank\"\u003eDimensions\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"http:\/\/www.diyaudio.com\/media\/build-guides\/diyaudio-diyab-build-guide-v1.0.pdf\" target=\"_blank\"\u003eBuild Guide\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"http:\/\/www.diyaudio.com\/forums\/solid-state\/192431-diyab-amp-honey-badger.html\" target=\"_blank\"\u003eGeneral Discussion Thread\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003ctable class=\"data-table\" id=\"product-attribute-specs-table\" style=\"width: 100%; height: 97.969px;\"\u003e\n\u003ctbody\u003e\n\u003ctr class=\"even\" style=\"height: 19.5938px;\"\u003e\n\u003cth class=\"label\" style=\"width: 51.2389%; height: 19.5938px;\"\u003eDimensions\u003c\/th\u003e\n\u003ctd class=\"data last\" style=\"width: 45.9039%; height: 19.5938px;\"\u003e253mm x 76mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"odd\" style=\"height: 19.5938px;\"\u003e\n\u003cth class=\"label\" style=\"width: 51.2389%; height: 19.5938px;\"\u003eMounting holes\u003c\/th\u003e\n\u003ctd class=\"data last\" style=\"width: 45.9039%; height: 19.5938px;\"\u003eUMS Heatsink Compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\" style=\"height: 19.5938px;\"\u003e\n\u003cth class=\"label\" style=\"width: 51.2389%; height: 19.5938px;\"\u003eLayers\u003c\/th\u003e\n\u003ctd class=\"data last\" style=\"width: 45.9039%; height: 19.5938px;\"\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\" style=\"height: 19.5938px;\"\u003e\n\u003cth class=\"label\" style=\"width: 51.2389%; height: 19.5938px;\"\u003eBoard Revision\u003c\/th\u003e\n\u003ctd class=\"data last\" style=\"width: 45.9039%; height: 19.5938px;\"\u003e2.4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"diyAudio Store","offers":[{"title":"Default Title","offer_id":5941505732,"sku":"DIYP-DIYAB-224","price":39.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/products\/Honey_Badger_2.4-2.jpg?v=1508215685"},{"product_id":"burning-amplifier-complementary","title":"Burning Amplifier Complementary Bias \u0026 Output Stage","description":"\u003cp\u003eThis output stage can be used along with your choice of gain stage to create a Burning Amp.(See the Configuration Guide linked below)\u003c\/p\u003e\n\u003cp\u003eThe boards are the output-pair-per-channel configuration recommended by Nelson Pass.  If you want more output devices to make a truly massive amplifier, you will need to order an additional complete set.\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003ePlease visit the \u003c\/span\u003e\u003ca href=\"http:\/\/www.diyaudio.com\/forums\/diyaudio-store\/214012-burning-amplifiers.html\"\u003eBurning Amplifier Helpdesk Thread\u003c\/a\u003e\u003cspan\u003e for any questions you might have and for a definitive list of links to all articles and discussions about the Burning Amps.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eAdditional Information\u003c\/span\u003e\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/P-BAC-S4V20-bom.xls\" rel=\"noopener noreferrer\" target=\"_blank\"\u003eBill of Materials\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/P-BAC-S4V20-schematic.pdf\" rel=\"noopener noreferrer\" target=\"_blank\"\u003eSchematic\u003c\/a\u003e (\u003cstrong\u003ePLEASE NOTE\u003c\/strong\u003e  This schematic, which is Nelson's original, incorrectly shows 12xIRFP240 output devices. This design uses 6xIRFP240 and 6xIRFP9240. Please study the BOM and PCB part placement very carefully!)\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/P-BAC-S4V20-dimensions.zip\" rel=\"noopener noreferrer\" target=\"_blank\"\u003eDimensions\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/files\/burning-amplifier-configurations.pdf\" rel=\"noopener noreferrer\" target=\"_blank\"\u003eBurning Amplifier Configuration Guide\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ctable class=\"data-table\" id=\"product-attribute-specs-table\"\u003e\n\u003ctbody\u003e\n\u003ctr class=\"even\"\u003e\n\u003cth class=\"label\"\u003eDimensions\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e50mm x 50mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"odd\"\u003e\n\u003cth class=\"label\"\u003eMounting holes\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003eUMS Heatsink Compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eLayers\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"last odd\"\u003e\n\u003cth class=\"label\"\u003eBoard Revision\u003c\/th\u003e\n\u003ctd class=\"data last\"\u003e2.0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e","brand":"diyAudio Store","offers":[{"title":"Default Title","offer_id":5941630276,"sku":"DIYP-BAC-420","price":29.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/products\/DSC_0489.png?v=1448506669"},{"product_id":"m2x","title":"M2X","description":"\u003cp\u003eThe M2x is based upon the Nelson Pass \/ \u003ca href=\"https:\/\/www.firstwatt.com\/product\/m2\/\"\u003eFirst Watt M2 amplifier\u003c\/a\u003e. However, the first \"buffer\" stage of amplification has been placed on a removable daughter board, making it extremely easy to swap-in different first stage circuits. A total of five first stage circuit designs are provided, and naturally one of them is the Nelson Pass \/ First Watt original.\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"http:\/\/www.diyaudio.com\/forums\/pass-labs\/321925-diyaudio-watt-m2x.html\"\u003eRead the M2X thread on diyAudio\u003c\/a\u003e to learn more and join in the discussion.\u003c\/p\u003e\n\u003cp\u003eThe \u003ca href=\"http:\/\/www.diyaudio.com\/forums\/pass-labs\/321925-diyaudio-watt-m2x.html\"\u003eM2x\u003c\/a\u003e is a Push-Pull Class A amplifier circuit, with zero global feedback. It consists of 3 stages: an input buffer circuit (on a daughter card), followed by a passive auto-transformer for voltage gain, and finally a Class A MOSFET push pull output buffer. The sound of the M2x, as Nelson Pass puts it, is \"relaxed and lively.\"\u003cbr\u003e\u003cbr\u003eFive different input stage options are provided on PCB daughter cards:\u003c\/p\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cspan\u003e\u003cstrong\u003eISHIKAWA\u003c\/strong\u003e: \u003c\/span\u003eThe Nelson Pass original using Toshiba JFETs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMOUNTAIN VIEW:\u003c\/strong\u003e A single ended Class A circuit using a Fairchild JFET\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTUCSON\u003c\/strong\u003e: An IC opamp circuit using a highly regarded JFET-input chip from Burr Brown\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAUSTIN\u003c\/strong\u003e: A fully complementary, symmetric Diamond Buffer circuit using discrete bipolar transistors from ON Semi\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eNORWOOD\u003c\/b\u003e: An Analog Devices JFET opamp followed by a high bandwidth video driver (110 MHz!) from Harris\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003eThese different input circuit designs allow a builder many options, particularly when sourcing electronic components. For example, during times when the JFETs used in Nelson Pass's original (K170 + J74) are out of stock, one of the other daughter cards can be sourced, stuffed, soldered, and enjoyed in the listening room. Some early M2x builders report that they prefer the sound of these other cards, even more than the Nelson Pass original. Try them yourself and discover which one(s) YOU prefer.\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eHow might someone choose which of these to build? (Or, which of these to build \u003c\/span\u003e\u003ci\u003efirst?\u003c\/i\u003e\u003cspan\u003e) Here are some thoughts.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003e\u003cstrong\u003eISHIKAWA\u003c\/strong\u003e (using Toshiba or LS JFETs) has the absolutely lowest parts count and is the easiest to solder together. But those FETs are hard to find.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003e\u003cstrong\u003eTUCSON\u003c\/strong\u003e using the thru-hole OPA604 chip, is the lowest parts count board that doesn't use unobtainium devices. And the OPA604 opamp has JFET inputs, so if you love JFETs, it's one of the opamps you probably know and adore. Alternatively, TUCSON u\u003c\/span\u003e\u003cspan\u003esing the SMD OPA1611 chip, is the lowest distortion input stage of them all. Even lower than the Nelson Pass original. It only has one surface mount part; the rest of the board is thru-hole.\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003e\u003cstrong\u003eNORWOOD\u003c\/strong\u003e is all-SMD, just like the entire electronics industry has been for the last 20 years. Norwood includes a 200 mA driver IC, and a JFET input opamp from Analog Devices. Its output current capability is at least a factor of five greater than any of the other M2x input stages. If you're at all concerned about the input impedance of the output devices at HF, reflected from the transformer secondary back into the primary, Norwood can drive it better than all the others.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003e\u003cstrong\u003eMOUNTAIN VIEW\u003c\/strong\u003e uses single-ended, class A, discrete circuitry and no feedback. If you are a big believer in single ended class A, if you love this quote from a famous article by Nelson Pass...\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"padding-left: 30px;\"\u003e\u003cem\u003e\"For reproducing music as naturally as possible, push-pull operation is not the best approach. Air is not symmetric and does not have a push-pull characteristic. ... Only one linear circuit topology delivers the appropriate characteristic, and that is the single-ended amplifier. Single ended amplification only comes in pure class A,\"\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003e...then you probably are interested in listening to the Mountain View input stage.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003e\u003cstrong\u003eAUSTIN\u003c\/strong\u003e is a thru-hole board with 4X more components than the other boards; its resistors are \u003c\/span\u003e\u003ci\u003emounted vertically\u003c\/i\u003e\u003cspan\u003e to save PCB area. This permits a Diamond Buffer circuit with high performance, precision current source loads. Builders who love parts substitutions \/ optimizations will appreciate that Austin's PCB silkscreen doesn't indicate transistor orientation. Instead, transistor pins are labeled B, C, E in a perfect circle; allowing you to drop in Japanese 2SA\/2SC transistors (pinout ECB) or European BC transistors (pinout CBE) or American 2N transistors (pinout EBC) however you please. Austin is recommended ONLY for experienced builders. If you're a newbie, hire someone to solder your Austin board!!\u003c\/span\u003e\u003c\/p\u003e\n\u003ch4\u003ePower supply requirements\u003c\/h4\u003e\n\u003cp\u003eA bipolar power supply of (+\/- 24V) is required. The PSUs for almost all First Watt amplifiers including the F4, F5, F6, M2x, Aleph J, and Aleph Jzm are identical. The same PSU can be used for all of them.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eThe \u003ca href=\"https:\/\/diyaudiostore.com\/products\/simple-linear-bipolar-power-supply?_pos=1\u0026amp;_psq=simple\u0026amp;_ss=e\u0026amp;_v=1.0\" target=\"_blank\"\u003eSimple Linear Bipolar Power Supply\u003c\/a\u003e is the choice for DIYers that prefer a higher performance power supply, but enjoy the convenience of a full kit. For builders that prefer to choose their own parts, the PCBs are also available.\u003c\/li\u003e\n\u003cli\u003eThe \u003ca href=\"https:\/\/diyaudiostore.com\/collections\/power-supplies-accessories\/products\/universal-psu\" target=\"_blank\"\u003eUniversal Power Supply\u003c\/a\u003e PCBs allow the experienced DIYer to choose every part of their PSU or use what they have in their spare parts bin.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eChassis suggestions\u003c\/h4\u003e\n\u003cp\u003eThe \u003ca href=\"https:\/\/diyaudiostore.com\/collections\/chassis-enclosure\/products\/2025-deluxe-chassis-3u\" target=\"_blank\"\u003e3U Deluxe\u003c\/a\u003e is an excellent choice. For builders that want more space and\/or may want to build a bigger amplifier in the future, the \u003ca href=\"https:\/\/diyaudiostore.com\/collections\/chassis-enclosure\/products\/2025-deluxe-chassis-4u\" target=\"_blank\"\u003e4U Deluxe\u003c\/a\u003e or \u003ca href=\"https:\/\/diyaudiostore.com\/collections\/chassis-enclosure\/products\/2025-deluxe-chassis-4u\" target=\"_blank\"\u003e5U Deluxe \u003c\/a\u003eare great choices.  We also have a \u003ca href=\"https:\/\/diyaudiostore.com\/collections\/chassis\/products\/deluxe-chassis-back-panel-parts-kit\"\u003eback panel parts kit\u003c\/a\u003e to make life easier, and don’t forget the \u003ca href=\"https:\/\/diyaudiostore.com\/collections\/consumables\/products\/keratherm-transistor-insulators\"\u003eKeratherm\u003c\/a\u003e.\u003c\/p\u003e\n\u003ch4\u003eOutput Power\u003c\/h4\u003e\n\u003cp\u003eAs with most First Watt amplifiers, the power output is 25WPC into 8 ohms.\u003c\/p\u003e","brand":"diyAudio Store","offers":[{"title":"Default Title","offer_id":12699843002402,"sku":"DIYP-M2X-C10","price":29.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1006\/5046\/products\/DSC0687.jpg?v=1536784997"}],"url":"https:\/\/diyaudiostore.com\/collections\/pcb-power-amplifier.oembed","provider":"The diyAudio Store","version":"1.0","type":"link"}