{"product_id":"krell-duo-125-xd-stereo-power-amplifier","title":"KRELL Duo 125 XD Stereo Power Amplifier","description":"\u003ch2\u003eIntroducing the 125 XD Stereo Power Amplifier\u003cmeta charset=\"utf-8\"\u003e\n\u003c\/h2\u003e\n\u003ch2\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1040\/6126\/files\/KRELL-Duo-125-XD-Stereo-Power-Amplifier-side-Vinyl-Revival_9c2aafb6-6a4a-4a45-a2c1-b4514b48fba5.png?v=1771911213\"\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003e\u003cem\u003e\u003cstrong\u003eAudio Engineering at its Finest with \u003c\/strong\u003e\u003c\/em\u003e\u003c\/span\u003e\u003cem\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003eKrell’s New XD™ Technology\u003c\/span\u003e\u003c\/strong\u003e\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003eKrell’s XD (Xtended Dynamics, Dimensionality \u0026amp; Detail) upgrade for the iBias amplifiers takes an already great sounding amplifier and raises its performance to the next level. XD is a classic example of Krell’s continuous R\u0026amp;D efforts reaping benefits across multiple product lines. During the development of the K-300i Integrated Amplifier we discovered substantial sonic improvements by lowering the output impedance below traditional norms. When applying this technique to our existing line of amplifiers, the improvement was so substantial, it deserved its own, unique designation—XD.\u003c\/p\u003e\n\u003cp\u003eIt was no simple matter merely lowering the output impedance. This affects the amplifier’s stability and transient response, so each stage prior to the output stage had to be re-tuned to work optimally with the lower output impedance. This lower output impedance exerts more control over the speaker drivers, and damps out unwanted vibrational modes—allowing a more accurate reproduction of the original signal.\u003c\/p\u003e\n\u003ch4\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003eKrell Class A iBias™ Technology\u003c\/span\u003e\u003c\/h4\u003e\n\u003cp\u003eKrell’s history is rich with breakthrough Class A amplifiers that have helped build the Krell legacy of offering the best sounding amplifiers available. Our revolutionary, patent pending circuit delivers true Class A operation without the excessive heat and wasted energy of conventional designs.\u003c\/p\u003e\n\u003ch4\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003ePower Supply Highlights\u003c\/span\u003e\u003c\/h4\u003e\n\u003cp\u003ePower supply technology has always been an important contributor to the Krell sound. The power supplies of our Krell iBias Class A amplifiers have been optimized for use with the iBias circuit. Depending on the model, up to four toroidal transformers feed amplifier modules that include the audio circuitry, rectifier, and power supply filtering mounted to an individual heat sink. This design shortens the electrical path from the power supply to the output transistors, reducing the overall impedance and allowing the circuit to respond faster and control the speakers even better and more accurately.\u003c\/p\u003e\n\u003cp\u003eUnlike traditional Class A amplifiers, iBias Class A amps have a compact design that allows rack-mounting, making them ideal for custom installation as well as traditional audiophile systems. This convenient form factor is made possible through thermostatically controlled ventilation fans. The fans used are specifically chosen for quiet operation, and operate at the speed required to maintain the ideal internal temperature. They run only during periods of peak energy demand – when the music is at its loudest – so they are inaudible in normal use.\u003c\/p\u003e\n\u003ch4\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003eNetwork Connectivity\u003c\/span\u003e\u003c\/h4\u003e\n\u003cp\u003eThe new amplifiers include RJ 45 Ethernet connectivity and an internal web page that is accessible from any smartphone, tablet, or laptop. Network connectivity brings convenience, monitoring, and reporting to end users. Amplifier configuration options include display brightness and timeout. For energy conservation, the amplifiers can be programmed to power off at a preset time of inactivity. Individual channels can be muted and firmware updates can be initiated from the web server.\u003c\/p\u003e\n\u003cp\u003eOnce the amplifier is connected to a network router with Internet access, the amplifier’s advanced protection systems are now viewable on an Internet-connected device. Excessive current, output DC, fan speeds, short circuit, and overheating are all monitored in real time. If an issue occurs, the fault is displayed on the front panel and reported on the web server interface. Emails will automatically be sent to as many as three email addresses to notify the end user and\/or the dealer of the condition.\u003c\/p\u003e\n\u003ch4\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003e\u003cimg alt=\"KRELL Duo 125 XD Stereo Power Amplifier, front\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1040\/6126\/files\/KRELL-Duo-125-XD-Stereo-Power-Amplifier-front-Vinyl-Revival.png?v=1771910865\"\u003e\u003c\/span\u003e\u003c\/h4\u003e\n\u003ch4\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003eAdvanced Circuitry\u003c\/span\u003e\u003c\/h4\u003e\n\u003cp\u003eThe new iBias circuitry is built on a foundation of core Krell circuit technologies. All signal gain is realised in the current domain using proprietary multiple-output current mirrors with extraordinary open loop linearity. Each amplifier channel uses all discrete components. There are no generic integrated circuits or op amps used anywhere. Gain is distributed among several stages, allowing each to have a large linear operating area.\u003c\/p\u003e\n\u003cp\u003eAudio signal voltages are converted to current at the amplifier input, and the audio signal remains in the current domain throughout the entire amplifier.\u003c\/p\u003e\n\u003cp\u003eCurrent mirrors in the final gain stages use a new output power device that operates at a 73% higher voltage, delivers almost 10% more current, and offers 120 watts of additional power handling capability as compared to other devices.\u003c\/p\u003e\n\u003cp\u003eWith this combination, the iBias amplifiers may now deliver substantially more power while using a smaller footprint. Normally used in demanding, high-bandwidth video circuits, these transistors allow the design of gain stages with superb accuracy and very low distortion. The signal path is fully complementary and fully balanced from input to output. Independent complementary pre driver and driver stages for the positive and negative output transistors make the output stages extremely fast and linear. This unique circuit is impervious to low-impedance or reactive loads; it simply drives any loudspeaker with absolute confidence, achieving the very best possible sonic results.\u003c\/p\u003e\n\u003cp\u003eMost amplifiers use coupling capacitors in the signal path to block DC and prevent damaging offset voltages from reaching your speakers. Krell amplifiers are fully direct-coupled, with no capacitors in the audio signal path. This design gives the Krell amplifiers lower internal impedance, which allows firmer, more precise control of your speakers. It also provides flatter, more extended low-frequency response, because coupling capacitors not only block DC but also affect the lowest bass frequencies. Krell employs expensive, non intrusive DC servos that remove DC without impacting the musical signal. Thus, the iBias Class A amplifiers deliver the full breadth of the music with detail, impact and space intact.\u003c\/p\u003e\n\u003ch4\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003eEverything Audiophiles \u0026amp; Home Theatre Buffs could ever ask for and some\u003c\/span\u003e\u003c\/h4\u003e\n\u003cp\u003eKrell iBias Class A amplifiers are the first to deliver the rich musicality of Class A amplifiers combined with the uncompromised dynamics of classic Krell amplifiers, and the efficiency and low power consumption of Class G and H amplifiers.\u003c\/p\u003e\n\u003cp\u003eBecause the iBias circuit eliminates crossover distortion, the amplifier is able to resolve more of the detail and microdynamics in even the best analog recordings—simply put, the music ‘breathes’. Whether an iBias amplifier is called on to reproduce the extreme dynamic range of high-resolution digital files, the minute intricacies of a 45-rpm, 180-gram vinyl record, or the complexity of today’s latest blockbuster action film, it does so without altering or abating the music in any way.\u003c\/p\u003e\n\u003cp\u003eThe iBias amplifiers’ unprecedented ability to retrieve the subtlest details gives their sound an incredible dimensionality, with an ambient, broad and extraordinarily deep soundstage. As spacious as the sound is, though, the amplifiers are still able to produce pinpoint stereo imaging if the recording calls for it.\u003c\/p\u003e\n\u003cp\u003eIt’s all the power and control for which Krell has always been famous, with a level of resolution and musicality in the midrange and treble that has simply never been heard before.\u003c\/p\u003e\n\u003cp\u003eIn short, the new patent pending iBias Class A Krell amplifiers give today’s audiophiles and home theater fans everything they could possibly want in an amplifier. \u003c\/p\u003e\n\u003ch4\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003e\u003cimg alt=\"KRELL Duo 125 XD Stereo Power Amplifier, back\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1040\/6126\/files\/KRELL-Duo-125-XD-Stereo-Power-Amplifier-back-Vinyl-Revival.png?v=1771910921\"\u003e\u003c\/span\u003e\u003c\/h4\u003e\n\u003ch4\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003eTechnical Specifications\u003c\/span\u003e\u003c\/h4\u003e\n\u003cp\u003e\u003cstrong\u003eFrequency response\u003cbr\u003e\u003c\/strong\u003e20 Hz to 20 kHz +0, -0.08 dB\u003cbr\u003e0.25 Hz to 100 kHz +0, -3 dB\u003c\/p\u003e\n\u003cdiv class=\"elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-1731cf9\" data-element_type=\"column\" data-id=\"1731cf9\"\u003e\n\u003cdiv class=\"elementor-column-wrap elementor-element-populated\"\u003e\n\u003cdiv class=\"elementor-widget-wrap\"\u003e\n\u003cdiv class=\"elementor-element elementor-element-4967650 elementor-widget elementor-widget-text-editor\" data-element_type=\"widget\" data-id=\"4967650\" data-widget_type=\"text-editor.default\"\u003e\n\u003cdiv class=\"elementor-widget-\"\u003e\n\u003cdiv class=\"elementor-text-editor elementor-clearfix\"\u003e\n\u003cp\u003e\u003cstrong\u003eSignal-to-noise ratio\u003c\/strong\u003e\u003cbr\u003e\u0026gt;95 dB, wideband, unweighted, referred to full power output\u003cbr\u003e\u0026gt;112 dB, “A”-weighted\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGain\u003c\/strong\u003e\u003cbr\u003e25.8 dB\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eTotal harmonic distortion\u003c\/strong\u003e\u003cbr\u003e\u0026lt;0.03% at 1 kHz, at 125 W, 8 Ω\u003cbr\u003e\u0026lt;0.17% at 20 kHz, at 125 W, 8 Ω\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eInput Impedance\u003c\/strong\u003e\u003cbr\u003eSingle-ended: 100 kΩ\u003cbr\u003eBalanced: 200 kΩ\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eInput sensitivity\u003c\/strong\u003e\u003cbr\u003eSingle-ended or balanced: 1.63 V RMS\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutput power\u003c\/strong\u003e\u003cbr\u003e125 W RMS at 8 Ω\u003cbr\u003e250 W RMS at 4 Ω\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutput voltage\u003c\/strong\u003e\u003cbr\u003e89.4 V peak-to-peak\u003cbr\u003e31.6 V RMS\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutput current\u003c\/strong\u003e\u003cbr\u003e18 A peak\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\u003cp\u003e\u003cstrong\u003eSlew rate\u003c\/strong\u003e\u003cbr\u003e40 V\/μs\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutput impedance\u003c\/strong\u003e\u003cbr\u003e\u0026lt;0.015Ω, 20 Hz to 20 kHz\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDamping factor\u003c\/strong\u003e\u003cbr\u003e\u0026gt;530, 20 Hz to 20 kHz, referred to 8 Ω\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePower consumption\u003cbr\u003e\u003c\/strong\u003eStandby: 1 W\u003cbr\u003eIdle: 58 W\u003cbr\u003eMaximum: 1350 W\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHeat output\u003cbr\u003e\u003c\/strong\u003eStandby: 3.42 BTU\/hr.\u003cbr\u003eIdle: 198 BTU\/hr.\u003cbr\u003eMaximum: 4617 BTU\/hr.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eInputs\u003cbr\u003e\u003c\/strong\u003e2 single-ended via RCA connector\u003cbr\u003e2 balanced via XLR connector\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutputs\u003cbr\u003e\u003c\/strong\u003e2 pairs binding posts\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDimensions (W x H x D)\u003cbr\u003e\u003c\/strong\u003e434 x 194x 536 mm \u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWeight\u003cbr\u003e\u003c\/strong\u003e27.3 kg (shipping)\u003cbr\u003e22.7 kg (unit only)\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWarranty\u003c\/strong\u003e\u003cstrong style=\"font-family: -apple-system, BlinkMacSystemFont, 'San Francisco', 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif; font-size: 0.875rem;\"\u003e\u003cbr\u003e\u003c\/strong\u003e5 Years for Parts and Labour\u003c\/p\u003e\n\u003cdiv class=\"hfeed site grid-container grid-parent\" id=\"page\"\u003e\n\u003cdiv class=\"site-content\" id=\"content\"\u003e\n\u003cdiv class=\"elementor elementor-810 elementor-location-single post-1060 page type-page status-publish category-technical-specifications\" data-elementor-id=\"810\" data-elementor-post-type=\"elementor_library\" data-elementor-type=\"single\"\u003e\n\u003cdiv class=\"elementor-section-wrap\"\u003e\n\u003csection class=\"elementor-section elementor-top-section elementor-element elementor-element-0ea060c elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-element_type=\"section\" data-id=\"0ea060c\"\u003e\n\u003cdiv class=\"elementor- elementor-column-gap-default\"\u003e\n\u003cdiv class=\"elementor-row\"\u003e\n\u003cdiv class=\"elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-db2b138\" data-element_type=\"column\" data-id=\"db2b138\"\u003e\n\u003cdiv class=\"elementor-column-wrap elementor-element-populated\"\u003e\n\u003cdiv class=\"elementor-widget-wrap\"\u003e\n\u003cdiv class=\"elementor-element elementor-element-09d2897 elementor-widget elementor-widget-text-editor\" data-element_type=\"widget\" data-id=\"09d2897\" data-widget_type=\"text-editor.default\"\u003e\n\u003cdiv class=\"elementor-widget-\"\u003e\n\u003cdiv class=\"elementor-text-editor elementor-clearfix\"\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp data-prosemirror-content-type=\"node\" data-prosemirror-node-name=\"paragraph\" data-prosemirror-node-block=\"true\" data-pm-slice=\"1 1 []\"\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003e\u003cem data-prosemirror-content-type=\"mark\" data-prosemirror-mark-name=\"em\"\u003e*This information has been obtained from Manufacturers website. We advise that Price, Features \u0026amp; Specifications are subject change without notice.\u003c\/em\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp data-prosemirror-content-type=\"node\" data-prosemirror-node-name=\"paragraph\" data-prosemirror-node-block=\"true\"\u003e\u003cspan style=\"color: rgb(0, 170, 255);\"\u003eE\u0026amp;OE\u003c\/span\u003e\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\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"KRELL","offers":[{"title":"Default Title","offer_id":42586204700770,"sku":"KRELL-Duo-125-XD","price":13999.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1040\/6126\/files\/krell-duo-125-xd-stereo-power-amplifierpower-amplifierskrell-1805102.png?v=1775628310","url":"https:\/\/www.vinylrevival.com.au\/products\/krell-duo-125-xd-stereo-power-amplifier","provider":"Vinyl Revival","version":"1.0","type":"link"}