{"product_id":"m4-replica-of-british-sugden-sf60-kit-audiophile-grade-amplifier-board-classic-sounding-outperforms-lm3886-tda7293","title":"M4 | Replica of British Sugden SF60 Kit | Audiophile-Grade Amplifier Board | Classic Sounding | Outperforms LM3886 \u0026 TDA7293","description":"\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003eNote:\u003c\/strong\u003e Many have reported issues such as operating point drift or other problems after swapping op-amps. In fact, the use of \u003cstrong\u003eAD827\u003c\/strong\u003e and \u003cstrong\u003eLME49720\u003c\/strong\u003e is not recommended, as these two op-amps require relatively low feedback resistor values. \u003cstrong\u003eDirectly replacing with dual op-amps from the OPA or MUSES series will work without any issues.\u003c\/strong\u003e Examples include the \u003cstrong\u003eOPA2604, OPA2132, OPA1612, MUSES8920, MUSES02, OP275, and TL1057\u003c\/strong\u003e, all of which are fully compatible and can serve as drop-in replacements.\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eThe resistor marked with \u003cstrong\u003e“?”\u003c\/strong\u003e on the board has a value of \u003cstrong\u003e3.9 kΩ\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003eFinished board weight:\u003c\/strong\u003e approx. 205 g (net weight)\u003cbr\u003e\u003cstrong\u003eFinished board + capacitors + Toshiba heat sink:\u003c\/strong\u003e approx. 797 g\u003cbr\u003e\u003cstrong\u003eFinished board + capacitors + ON Semiconductor heat sink:\u003c\/strong\u003e approx. 767 g\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eThe M4 circuit is derived from a replication of the British Sugden SF-60. This British circuit is truly remarkable, reproducing musical melodies that captivate and immerse the listener completely. Its pure and natural sound quality is thoroughly embodied in the circuit design. Compared to the Audiolab 8000A, it clearly surpasses it by two levels, especially in the layering and refinement of the mid-to-high frequencies.\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eThe performance of this amplifier far exceeds that of amplifiers using the NEC UPC2581V as a driver transistor. Its midrange, in particular, is much more listenable and comfortable. More importantly, it allows for the replacement of the input op-amp, offering the enjoyment and satisfaction of tailoring the sound signature and performing upgrades. If sufficient heat sinking is provided, the unit can even be adjusted for pure Class A output! The product includes complete overcurrent protection, delayed startup protection, and output DC protection to ensure the safety of your valuable speakers.\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003ePurchase options include either a component kit or a finished board. The main heat sink must be purchased separately: thickened version ($14).\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003ePower Supply Voltage:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eAC22VX2 to AC36VX2\u003cbr\u003e\u003cstrong\u003ePCB Dimensions:\u003c\/strong\u003e 153 x 128 mm\u003cbr\u003e\u003cstrong\u003eOutput Power:\u003c\/strong\u003e 150W + 150W (4Ω), 100W + 100W (8Ω)\u003cbr\u003e\u003cstrong\u003eOptional Power Transistors:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eON Semiconductor complementary pair NJW0281\/NJW0302\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eToshiba 2SC5200\/2SA1943\u003cbr\u003e\u003cstrong\u003eFrequency Response:\u003c\/strong\u003e 10 Hz – 40 kHz\u003cbr\u003e\u003cstrong\u003eIncluded Accessories:\u003c\/strong\u003e Mica insulators, mounting screws, fixing brass spacers\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003eNotes on Transistor Selection:\u003c\/strong\u003e\u003cbr\u003eThe ON Semiconductor transistors offer excellent technical performance with well-layered sound, while the Toshiba transistors deliver warm, captivating tonality and outstanding bass.\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003ePurchase Note:\u003c\/strong\u003e\u003cbr\u003eBoth the kit and the finished board \u003cstrong\u003edo not include\u003c\/strong\u003e the two 10000 µF main filter capacitors, which must be purchased separately.\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003eKey Components:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eDouble-sided immersion gold PCB\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eGerman WIMA MKS coupling capacitors\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eMilitary-grade 718 series resistors with copper leads\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eJapanese Omron relay\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eImported original transistors\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eJapanese Nippon Chemi-Con (Black Gate) capacitors\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003eSanken rectifier bridge\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003eAdjustment:\u003c\/strong\u003e\u003cbr\u003eThis board is very simple to adjust. You only need to measure and set the quiescent current of the output transistors.\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/1_0cfe046a814c17284c301e26e59fbe4b_4829ce70-121e-4d15-8d42-237e594e59e5.webp?v=1775880614\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/2_9dc1ea9cf3c028ec89cc3159f7e22ee9_deb1865a-84f5-4fd3-b669-f34c43cd77e9.webp?v=1775880631\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/image-23.webp?v=1775880643\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/10_O1CN01F1lZBJ1OQBwA6eyX6_88221699-1047x1536.webp?v=1775880658\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/image-5-6-1024x1014.webp?v=1775880671\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/image-8-4-1176x1536.webp?v=1775880682\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/13_O1CN014ZDfEo1OQBzQyk6Xs_88221699.webp?v=1775880696\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/3_O1CN01uRL24T1OQBzPWNE8z_88221699-1.webp?v=1775880735\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/5_O1CN011d0H1o22OtXczPEbb_6000000007111-0-cbu_global_ai_agent-1.webp?v=1775880752\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/image-1-6.webp?v=1775880763\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/image-2-5.webp?v=1775880781\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/image-9-4.webp?v=1775880793\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/19_O1CN01Do2xRE1OQBwCV3iFF_88221699-1024x991.webp?v=1775880808\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003eCopper Leads of Resistors\u003c\/strong\u003e\u003cspan\u003e: Noticeably thicker and sturdier than standard resistors, comparable to those used in DALE brand resistors.\u003c\/span\u003e\u003cbr\u003e\u003cstrong\u003eTemperature Coefficient\u003c\/strong\u003e\u003cspan\u003e: 25-50 pp\u003c\/span\u003e\u003cbr\u003e\u003cstrong\u003ePower Rating\u003c\/strong\u003e\u003cspan\u003e: 1\/4W\u003c\/span\u003e\u003cbr\u003e\u003cstrong\u003eTolerance\u003c\/strong\u003e\u003cspan\u003e: 1% (indicated by 5 color bands)\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cspan\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/21_O1CN01H2ToNm1OQBzPAWznd_88221699.webp?v=1775880821\" alt=\"\"\u003e\u003c\/span\u003e\u003c\/p\u003e","brand":"GoMakerHive: Ignite Your Spark into a Blaze.","offers":[{"title":"Kit (with ON Semiconductor power transistors)","offer_id":66511469478192,"sku":null,"price":89.0,"currency_code":"USD","in_stock":true},{"title":"Kit (with Toshiba power transistors)","offer_id":66511469510960,"sku":null,"price":99.0,"currency_code":"USD","in_stock":true},{"title":"Finished board (with ON Semiconductor power transistors)","offer_id":66511469543728,"sku":null,"price":119.0,"currency_code":"USD","in_stock":true},{"title":"Finished board (with Toshiba power transistors)","offer_id":66511469576496,"sku":null,"price":129.0,"currency_code":"USD","in_stock":true},{"title":"300w pure copper wire transformer","offer_id":66511469609264,"sku":null,"price":99.0,"currency_code":"USD","in_stock":true},{"title":"Thickened heat sink (mounting holes drilled free of charge)","offer_id":66511469642032,"sku":null,"price":14.0,"currency_code":"USD","in_stock":true},{"title":"Finished board + capacitors + heat sink (Toshiba version)","offer_id":66511469674800,"sku":null,"price":179.0,"currency_code":"USD","in_stock":true},{"title":"Finished board + capacitors + heat sink (ON Semiconductor version)","offer_id":66511469707568,"sku":null,"price":169.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0972\/2367\/2112\/files\/1_0cfe046a814c17284c301e26e59fbe4b.webp?v=1775904826","url":"https:\/\/gomakerhive.com\/products\/m4-replica-of-british-sugden-sf60-kit-audiophile-grade-amplifier-board-classic-sounding-outperforms-lm3886-tda7293","provider":"GoMakerHive: Ignite Your Spark into a Blaze.","version":"1.0","type":"link"}