{"product_id":"marshall-st20h-studio-jtm-20w-head","title":"Marshall ST20H Studio JTM 20w Head","description":"\u003csection class=\"text-token-text-primary w-full focus:outline-none [--shadow-height:45px] has-data-writing-block:pointer-events-none has-data-writing-block:-mt-(--shadow-height) has-data-writing-block:pt-(--shadow-height) [\u0026amp;:has([data-writing-block])\u0026gt;*]:pointer-events-auto R6Vx5W_threadScrollVars scroll-mb-[calc(var(--scroll-root-safe-area-inset-bottom,0px)+var(--thread-response-height))] scroll-mt-(--header-height)\" dir=\"auto\" data-turn-id=\"bf643bb6-5728-47aa-9e78-acb3aee5385d\" data-testid=\"conversation-turn-107\" data-scroll-anchor=\"false\" data-turn=\"user\"\u003e\u003c\/section\u003e\n\u003csection class=\"text-token-text-primary w-full focus:outline-none [--shadow-height:45px] has-data-writing-block:pointer-events-none has-data-writing-block:-mt-(--shadow-height) has-data-writing-block:pt-(--shadow-height) [\u0026amp;:has([data-writing-block])\u0026gt;*]:pointer-events-auto [content-visibility:auto] supports-[content-visibility:auto]:[contain-intrinsic-size:auto_100lvh] R6Vx5W_threadScrollVars scroll-mb-[calc(var(--scroll-root-safe-area-inset-bottom,0px)+var(--thread-response-height))] scroll-mt-[calc(var(--header-height)+min(200px,max(70px,20svh)))]\" dir=\"auto\" data-turn-id=\"request-69e13238-dcc4-8325-bf49-225b849a242e-3\" data-testid=\"conversation-turn-108\" data-scroll-anchor=\"false\" data-turn=\"assistant\"\u003e\n\u003cdiv class=\"text-base my-auto mx-auto pb-10 [--thread-content-margin:var(--thread-content-margin-xs,calc(var(--spacing)*4))] @w-sm\/main:[--thread-content-margin:var(--thread-content-margin-sm,calc(var(--spacing)*6))] @w-lg\/main:[--thread-content-margin:var(--thread-content-margin-lg,calc(var(--spacing)*16))] px-(--thread-content-margin)\"\u003e\n\u003cdiv class=\"[--thread-content-max-width:40rem] @w-lg\/main:[--thread-content-max-width:48rem] mx-auto max-w-(--thread-content-max-width) flex-1 group\/turn-messages focus-visible:outline-hidden relative flex w-full min-w-0 flex-col agent-turn\"\u003e\n\u003cdiv class=\"flex max-w-full flex-col gap-4 grow\"\u003e\n\u003cdiv data-message-author-role=\"assistant\" data-message-id=\"ac470a9c-05e3-4c43-b0b0-17a21f9b0595\" dir=\"auto\" data-message-model-slug=\"gpt-5-3\" class=\"min-h-8 text-message relative flex w-full flex-col items-end gap-2 text-start break-words whitespace-normal outline-none keyboard-focused:focus-ring [.text-message+\u0026amp;]:mt-1\" data-turn-start-message=\"true\" tabindex=\"0\"\u003e\n\u003cdiv class=\"flex w-full flex-col gap-1 empty:hidden\"\u003e\n\u003cdiv class=\"markdown prose dark:prose-invert w-full wrap-break-word dark markdown-new-styling\"\u003e\n\u003cp data-start=\"36\" data-end=\"52\"\u003eWeight: 20.4 lbs\u003c\/p\u003e\n\u003cp data-start=\"66\" data-end=\"428\"\u003eThe Marshall ST20H Studio JTM Head is a UK-built, all-valve amplifier inspired by the original JTM45, delivering a wide range of tones from smooth cleans to classic crunch. Its dual-channel, bridgeable design allows players to blend the Normal and High Treble voices for a more tailored sound, offering flexibility that goes beyond traditional single-voice amps.\u003c\/p\u003e\n\u003cp data-start=\"430\" data-end=\"757\"\u003eWith a built-in power reduction from 20 watts down to 5 watts, the ST20H maintains its tonal character at lower volumes, making it practical for studio, rehearsal, and smaller stage environments. Combined with modern features like a switchable FX loop and DI output, it balances vintage-inspired tone with real-world usability.\u003c\/p\u003e\n\u003ch2 data-section-id=\"10btkw6\" data-start=\"759\" data-end=\"772\"\u003eHighlights\u003c\/h2\u003e\n\u003cul data-start=\"773\" data-end=\"1042\"\u003e\n\u003cli data-section-id=\"s4eyiu\" data-start=\"773\" data-end=\"831\"\u003eUK-built all-valve head inspired by the original JTM45\u003c\/li\u003e\n\u003cli data-section-id=\"1u0mslf\" data-start=\"832\" data-end=\"889\"\u003e20W to 5W power reduction for flexible volume control\u003c\/li\u003e\n\u003cli data-section-id=\"13jcg3e\" data-start=\"890\" data-end=\"945\"\u003eDual, bridgeable channels for blending tonal voices\u003c\/li\u003e\n\u003cli data-section-id=\"dthcbk\" data-start=\"946\" data-end=\"991\"\u003eClassic Marshall EQ with Presence control\u003c\/li\u003e\n\u003cli data-section-id=\"1owgdek\" data-start=\"992\" data-end=\"1042\"\u003eFX loop and DI output for modern functionality\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 data-section-id=\"1a3ueyz\" data-start=\"1044\" data-end=\"1061\"\u003eSpecifications\u003c\/h2\u003e\n\u003ch3 data-section-id=\"ynd8s6\" data-start=\"1063\" data-end=\"1071\"\u003eBody\u003c\/h3\u003e\n\u003cul data-start=\"1072\" data-end=\"1138\"\u003e\n\u003cli data-section-id=\"cuti83\" data-start=\"1072\" data-end=\"1096\"\u003eType: Amplifier Head\u003c\/li\u003e\n\u003cli data-section-id=\"mslji4\" data-start=\"1097\" data-end=\"1138\"\u003eDimensions: 19.7\" W x 9.4\" H x 9.1\" D\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-section-id=\"1ws7bh4\" data-start=\"1158\" data-end=\"1170\"\u003eHardware\u003c\/h3\u003e\n\u003cul data-start=\"1171\" data-end=\"1456\"\u003e\n\u003cli data-section-id=\"4yqgr0\" data-start=\"1171\" data-end=\"1205\"\u003eConstruction: Valve (All-Tube)\u003c\/li\u003e\n\u003cli data-section-id=\"1o7xpes\" data-start=\"1206\" data-end=\"1234\"\u003eChannels: 2 (Bridgeable)\u003c\/li\u003e\n\u003cli data-section-id=\"1bfki5l\" data-start=\"1235\" data-end=\"1323\"\u003eControls: Normal\/Loudness II, High Treble\/Loudness I, Treble, Middle, Bass, Presence\u003c\/li\u003e\n\u003cli data-section-id=\"j3ha8a\" data-start=\"1324\" data-end=\"1367\"\u003eInputs: 4 x 1\/4\" (High\/Low Sensitivity)\u003c\/li\u003e\n\u003cli data-section-id=\"1hau21v\" data-start=\"1368\" data-end=\"1413\"\u003eSpeaker Outputs: 5 x 1\/4\" (16Ω \/ 8Ω \/ 4Ω)\u003c\/li\u003e\n\u003cli data-section-id=\"3cwtt7\" data-start=\"1414\" data-end=\"1456\"\u003eEffects Loop: Yes (Series, Switchable)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-section-id=\"bdnvfb\" data-start=\"1458\" data-end=\"1473\"\u003eElectronics\u003c\/h3\u003e\n\u003cul data-start=\"1474\" data-end=\"1617\"\u003e\n\u003cli data-section-id=\"fviuuq\" data-start=\"1474\" data-end=\"1509\"\u003eWattage: 20W (switchable to 5W)\u003c\/li\u003e\n\u003cli data-section-id=\"1juto4s\" data-start=\"1510\" data-end=\"1565\"\u003ePreamp Tubes: 2 x ECC83, 1 x ECC83 (phase splitter)\u003c\/li\u003e\n\u003cli data-section-id=\"ei4aeu\" data-start=\"1566\" data-end=\"1591\"\u003ePower Tubes: 2 x 5881\u003c\/li\u003e\n\u003cli data-section-id=\"1hyzati\" data-start=\"1592\" data-end=\"1617\"\u003eDI Output: Yes (1\/4\")\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-section-id=\"1gdwpis\" data-start=\"1619\" data-end=\"1636\"\u003eMiscellaneous\u003c\/h3\u003e\n\u003cul data-start=\"1637\" data-end=\"1897\"\u003e\n\u003cli data-section-id=\"5ka7ra\" data-start=\"1696\" data-end=\"1760\"\u003eCountry of Origin: Designed and engineered in UK, Made in UK\u003c\/li\u003e\n\u003cli data-section-id=\"11bm6j5\" data-start=\"1761\" data-end=\"1824\"\u003eIncluded Accessories: Detachable power cable, speaker cable\u003c\/li\u003e\n\u003cli data-section-id=\"179z9k4\" data-start=\"1825\" data-end=\"1897\"\u003eOther: Studio Series JTM platform with classic and blendable voicing\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 data-section-id=\"7ogr8f\" data-start=\"1899\" data-end=\"1933\"\u003eWhy Buy from Tone Shop Guitars?\u003c\/h2\u003e\n\u003cp data-start=\"1934\" data-end=\"2245\" data-is-last-node=\"\" data-is-only-node=\"\"\u003eAt Tone Shop Guitars, we pride ourselves on offering a curated selection of instruments backed by knowledgeable staff and exceptional customer service. Whether you're shopping online or visiting us in person, our goal is to help you find the right guitar and deliver a top-tier experience every step of the way.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e","brand":"Marshall","offers":[{"title":"Default Title","offer_id":48678865371393,"sku":"ST20H-U","price":1349.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0856\/7056\/files\/MarshallST20HStudioJTM20wHead.png?v=1777317539","url":"https:\/\/www.toneshopguitars.com\/products\/marshall-st20h-studio-jtm-20w-head","provider":"Tone Shop Guitars","version":"1.0","type":"link"}