{"product_id":"sugden-masterclass-spa-4-pure-class-a-stereo-power-amplifier","title":"Sugden Masterclass SPA-4 Pure Class A Stereo Power Amplifier","description":"\u003ch1\u003eSugden Masterclass SPA-4 – Pure Class A Stereo Power Amplifier\u003c\/h1\u003e\n\n\u003cp\u003e\u003cstrong\u003eThe Sugden Masterclass SPA-4 is a substantial pure Class A stereo power amplifier designed for refined, high-performance two-channel systems.\u003c\/strong\u003e Sharing its core amplifier circuit with the Masterclass MPA-4 monoblock, it combines generous current delivery, balanced and single-ended connectivity, and the understated musical character for which Sugden has become renowned.\u003c\/p\u003e\n\n\u003ch2\u003eOverview\u003c\/h2\u003e\n\n\u003cp\u003e\nThe SPA-4 offers the performance philosophy of Sugden’s Masterclass monoblocks in a single stereo chassis. Its pure Class A circuit is engineered to provide stable loudspeaker control while preserving fine detail, tonal texture and the natural flow of a recording.\n\u003c\/p\u003e\n\n\u003cp\u003e\nFor listeners who cannot accommodate a pair of large monoblock amplifiers, the SPA-4 provides a more practical route into Sugden’s premium pre\/power architecture. It partners naturally with the Masterclass LA-4 preamplifier, while its RCA and balanced inputs also allow straightforward integration with other high-quality preamplifiers and variable-output sources.\n\u003c\/p\u003e\n\n\u003ch2\u003eKey Benefits\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePure Class A operation:\u003c\/strong\u003e designed for smooth, continuous power delivery and a naturally coherent presentation.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBroad loudspeaker compatibility:\u003c\/strong\u003e Sugden specifies the SPA-4 for use with both smaller loudspeaker designs and larger systems.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBalanced system integration:\u003c\/strong\u003e balanced and single-ended inputs support a wide range of preamplifiers and source configurations.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSingle-chassis convenience:\u003c\/strong\u003e offers Masterclass stereo amplification without the space requirements of two monoblocks.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHandcrafted construction:\u003c\/strong\u003e assembled in Yorkshire by an experienced Sugden technician.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003ePure Class A stereo power amplifier\u003c\/li\u003e\n  \u003cli\u003eAmplifier circuit derived from the Masterclass MPA-4 monoblock\u003c\/li\u003e\n  \u003cli\u003eStereo single-ended line-level inputs\u003c\/li\u003e\n  \u003cli\u003eStereo balanced inputs\u003c\/li\u003e\n  \u003cli\u003eMulti-way locking loudspeaker binding posts\u003c\/li\u003e\n  \u003cli\u003e75W power output into 4Ω with both channels operating\u003c\/li\u003e\n  \u003cli\u003eWide 2Hz–200kHz bandwidth at the -3dB points\u003c\/li\u003e\n  \u003cli\u003eHandcrafted in Yorkshire, England\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eIdeal For\u003c\/h2\u003e\n\n\u003cp\u003e\nThe Sugden Masterclass SPA-4 is intended for serious stereo systems where the preamplifier and power amplifier are selected separately. It is particularly relevant for listeners who value tonal naturalness, soundstage scale and long-term musical engagement over extensive processing or additional features.\n\u003c\/p\u003e\n\n\u003cp\u003e\nIts substantial construction and Class A operating principle should be considered when planning ventilation and equipment support. Loudspeaker matching should also take account of room size, sensitivity and impedance, particularly where consistently high playback levels are required.\n\u003c\/p\u003e\n\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\n\u003ctable\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eProduct type\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003ePure Class A stereo power amplifier\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eInputs\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003eStereo line-level RCA and stereo balanced\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eOutputs\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003eStereo pair of multi-way locking loudspeaker binding posts\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eInput sensitivity\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003e1V for full output\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003ePower output\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003e75W into 4Ω, both channels operating\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eFrequency response\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003e15Hz–30kHz\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eBandwidth\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003e2Hz–200kHz at the -3dB points\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eSignal-to-noise ratio\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003eGreater than 85dB\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eDimensions (H × W × D)\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003e250 × 430 × 350mm\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eGross packed weight\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003e25kg\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eManufacture\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003eHandcrafted in Yorkshire, England\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhy We Selected This Product\u003c\/h2\u003e\n\n\u003cp\u003e\nAt ExclusivIT, we value amplification that combines a clear engineering philosophy with meaningful real-world performance. The SPA-4 offers the control and scale expected from a substantial power amplifier while maintaining the musical refinement associated with Sugden’s pure Class A designs.\n\u003c\/p\u003e\n\n\u003cp\u003e\nIts balanced and single-ended connectivity makes it easy to integrate into a carefully assembled system, while the single-chassis format provides a practical alternative to the larger MPA-4 monoblocks. For customers seeking a long-term power amplifier for a premium analogue or digital stereo system, the SPA-4 deserves close consideration.\n\u003c\/p\u003e","brand":"SUGDEN AUDIO","offers":[{"title":"Titanium","offer_id":54644359921987,"sku":"SUGDEN-MSSPA4","price":8400.0,"currency_code":"EUR","in_stock":true},{"title":"Graphite","offer_id":54644359954755,"sku":"SUGDEN-MSSPA4-G","price":8400.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0788\/2080\/2883\/files\/SPA4NoHandlesLR.avif?v=1784294431","url":"https:\/\/www.exclusivit.eu\/products\/sugden-masterclass-spa-4-pure-class-a-stereo-power-amplifier","provider":"ExclusivIT","version":"1.0","type":"link"}