{"product_id":"b2-audio-ref-four","title":"B² Audio REF FOUR","description":"\u003cp class=\"PDq2pG_selectionAnchorContainer\"\u003e\u003cbr\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eThe B² Audio REF FOUR was developed for discerning car audio enthusiasts who want to combine the highest sound quality with exceptional power reserves. The meticulously engineered Class A\/B power amplifier delivers exceptionally precise signal reproduction, high dynamic range, and stable power output even at low impedances. Thanks to extensive filter functions, variable input sensitivity, and a powerful power supply, the REF FOUR is suitable for both high-end front-channel systems and high-power multichannel or bridged applications\u003cspan class=\"PDq2pG_selectionAnchor\"\u003e\u003c\/span\u003e\u003c\/strong\u003e\u003c\/span\u003e.\u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eHigh-quality electronics, generously sized components, and comprehensive protection circuits ensure reliable operation even under demanding conditions. With its 1-ohm stability in stereo mode, the REF FOUR offers exceptional flexibility for performance-oriented car audio systems and delivers outstanding results in both the SQ and high-power categories\u003c\/strong\u003e\u003c\/span\u003e.\u003cbr\u003e\u003cbr\u003e \u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e\u003cspan\u003e\u003c\/span\u003e\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e\u003cspan style=\"text-decoration: underline;\"\u003eTechnical Specifications\u003c\/span\u003e\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eModel: B² Audio REF FOUR\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eAmplifier Class: Class A\/B\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4-Channel Full-Range Amplifier\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e1 ohm, stereo, stable\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e2 ohms, bridged, stable\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eRMS power at 12.5 volts:\u003c\/strong\u003e\u003c\/span\u003e\u003cul\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4 × 75 watts RMS at 4 ohms\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4 × 135 watts RMS at 2 ohms\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4 × 190 watts RMS at 1 ohm\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003c\/ul\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eRMS power at 13.8 volts:\u003c\/strong\u003e\u003c\/span\u003e\u003cul\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4 × 100 watts RMS at 4 ohms\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4 × 180 watts RMS at 2 ohms\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4 × 265 watts RMS at 1 ohm\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003c\/ul\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eRMS power at 14.4 volts:\u003c\/strong\u003e\u003c\/span\u003e\u003cul\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4 × 125 watts RMS at 4 ohms\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4 × 225 watts RMS at 2 ohms\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003e4 × 325 watts RMS at 1 ohm\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003c\/ul\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eFrequency response: 10 Hz – 30 kHz\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eSignal-to-noise ratio: \u0026gt;95 dB\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eTotal Harmonic Distortion (THD): \u0026lt;0.15% at 1 kHz\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eInput sensitivity: 0.1–8 volts\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eInput impedance: 47 kOhm\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eHigh-pass filter: 40 Hz – 4 kHz\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eLow-pass filter: 40 Hz – 4 kHz\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eBandpass mode available\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eVariable Crossover Networks\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eClass A Bias Mode for Optimized Sound Characteristics\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eOperating voltage: 11–15 volts\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003ePower connection: 4 AWG (20 mm²)\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eFuse rating: 3 × 40 A (120 A total)\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eBuilt-in protection circuits against:\u003c\/strong\u003e\u003c\/span\u003e\u003cul\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eShort circuits\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eSpeaker overload\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eVoltage faults\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\u003c\/ul\u003e\u003c\/li\u003e\n\u003cli style=\"font-weight: bold; color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cstrong\u003eDimensions (L × W × H): 390 × 219.5 × 65 mm\u003c\/strong\u003e\u003c\/span\u003e\u003cbr\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"B2 Audio","offers":[{"title":"Individually","offer_id":52714998923531,"sku":null,"price":799.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0655\/8063\/0283\/files\/B2-REF-FOUR_Amplifier_Main_image.jpg?v=1764197657","url":"https:\/\/mtiudio.com\/en\/products\/b2-audio-ref-four","provider":"MT Audio Shop","version":"1.0","type":"link"}