The Class A Series Models: Full Power Balanced 600c | 300c | 200c 650Mc | 350Mc | 250Mc with Krell CAST Technology KCT | KPS 25sc | KPS 28c with Krell CAST Technology KPE Reference | KPE Standard | KBX Class A power amplifier design has been a Krell tradition since the company's inception in 1980. Class A Series components are performance leaders in their respective product categories. Featuring incomparable build quality and superior circuit topologies, Class A products are the driving force of reference quality audio systems worldwide. The Krell Full Power Balanced 600c Stereo Power Amplifier (left) and the Krell Full Power Balanced 650Mc Monaural Power Amplifier (right) Full Power Balanced 600c Stereo Power Amplifier The Full Power Balanced 600c Stereo Power Amplifier is designed for the audiophile who wants the ultimate sound quality from a stereo amplifier with power capabilities of 600 Watts per channel into 8 Ohm, 1200 Watts per channel into 4 Ohm, and 2400 Watts per channel into 2 Ohm loudspeaker loads. Highlights Fully balanced circuitry from input to output insures signal integrity, rejects noise, and improves signal-to-noise ratios to deliver a "night and day" sonic difference when compared to typical single-ended circuitry. Computer regulated power supply provides consistent sound quality at wide dynamic range regardless of fluctuating line voltages. Current mode operation ensures wide bandwidth and accurate harmonic reproduction for lifelike sound reproduction. Class A operation to full rated output redistributes minor distortion by-products and delivers clear transient sounds and harmonically correct overtones. Proprietary Krell output and driver transistors assure substantial output current capability. Full Power Balanced 300c Stereo Power Amplifier The Full Power Balanced 300c Stereo Power Amplifier is designed for the audiophile who wants the ultimate sound quality from a stereo amplifier with power capabilities of 300 Watts per channel into 8 Ohm, 600 Watts per channel into 4 Ohm, and 1200 Watts per channel into 2 Ohm loudspeaker loads. Highlights Fully balanced circuitry from input to output insures signal integrity, rejects noise, and improves signal-to-noise ratios to deliver a "night and day" sonic difference when compared to typical single-ended circuitry. Computer regulated power supply provides consistent sound quality at wide dynamic range regardless of fluctuating line voltages. Current mode operation ensures wide bandwidth and accurate harmonic reproduction for lifelike sound reproduction. Class A operation to full rated output redistributes minor distortion by-products and delivers clear transient sounds and harmonically correct overtones. Proprietary Krell output and driver transistors assure substantial output current capability. Full Power Balanced 200c Stereo Power Amplifier The Full Power Balanced 200c Stereo Power Amplifier is designed for the audiophile who wants the ultimate sound quality from a stereo amplifier with power capabilities of 200 Watts per channel into 8 Ohm, 400 Watts per channel into 4 Ohm, and 800 Watts per channel into 2 Ohm loudspeaker loads. Highlights Fully balanced circuitry from input to output insures signal integrity, rejects noise, and improves signal-to-noise ratios to deliver a "night and day" sonic difference when compared to typical single-ended circuitry. Computer regulated power supply provides consistent sound quality at wide dynamic range regardless of fluctuating line voltages. Current mode operation ensures wide bandwidth and accurate harmonic reproduction for lifelike sound reproduction. Class A operation to full rated output redistributes minor distortion by-products and delivers clear transient sounds and harmonically correct overtones. Proprietary Krell output and driver transistors assure substantial output current capability. Sales Literature (File size 704K) The Krell Full Power Balanced 650Mc Monaural Power Amplifier (right) and the Krell Full Power Balanced 600c Stereo Power Amplifier (left) Full Power Balanced 650Mc Monaural Power Amplifier The Full Power Balanced 650Mc Power Amplifier is the most powerful amplifier in the Krell Full Power Balanced Series. It provides the monumental power output of 650 Watts into 8 Ohm, 1300 Watts into 4 Ohm, and 2600 Watts into 2 Ohm loudspeaker loads. It is built in limited quantities and by special order. The model for this power house came from a custom amplifier that C.E.O. Dan D’Agostino designed specifically to power large speakers like the Wilson Audio Grand Slam and the Martin Logan Statement as the front main speakers in his personal home theater system. Mr. D’Agostino was developing the Krell Audio + Video Standard Preamp/Processor at the time and needed an amplifier of unlimited power to get maximum output from his system. Highlights Krell Current Mode circuitry provides a seamless gain stage transition, wide bandwidth and a heightened level of sonic detail and transparency, with all the smoothness of natural music. Krell Class A, direct coupled, balanced circuitry provides outstanding musical reproduction. Dual toroidal power transformers give maximum power to the regulated supplies for unrivaled instantaneous power delivery. Available individually, in symmetrical pairs, and in three-piece and five-piece like groupings to best address application needs. Seven-stage Sustained Plateau Bias II delivers precise Class A power into any impedance at any level to optimize every speaker’s performance. Proprietary Krell output and driver transistors assure substantial output current capability. Full Power Balanced 350Mc Monaural Power Amplifier The Full Power Balanced 350Mc Monaural Power Amplifier delivers Class A power: 350 Watts into 8 Ohm, 700 Watts into 4 Ohm, and 1,400 Watts into 2 Ohm loudspeaker loads. It offers high power and Krell Full Power Balanced sound quality for high-end two channel as well as high-end multi-channel sound system applications. The substantial current capability of the Full Power Balanced 350Mc provides significant headroom for large loudspeakers, subwoofers, and systems with low sensitivity. Highlights Krell Class A, direct coupled, balanced circuitry provides outstanding musical reproduction. Dual gold plated output terminals facilitate bi-wire connections security and ease. Computer regulated power supply provides consistent sound quality at wide dynamic range regardless of fluctuating line voltages. Remote power turn on/off capability means convenient system operation. Krell output and driver transistors assure substantial output current capability and audiophile grade sound quality. Available individually, in symmetrical pairs, and in three-piece and five-piece groupings to best address application needs. Full Power Balanced 250Mc Monaural Power Amplifier The Full Power Balanced 250Mc Power Amplifier is designed for the demanding audiophile who prefers monaural operation and the home theater enthusiast who wants superior sound and system flexibility. It is an ideal amplifier for those who appreciate the special appeal of monaural power amplification and want the sonic advantages that Krell Full Power Balanced technology provides. Highlights Substantial Class A power output of 250 Watts into 8 Ohms, 500 Watts into 4 Ohms, and 1000 Watts into 2 Ohms assures tremendous reserves of dynamic headroom for the reproduction of any source material. Available individually, in symmetrical pairs, and in three-piece and five-piece groupings to best address application needs. Fully active regulation via microprocessor based regulators for precise control of bias circuits during fluctuating voltage conditions produce consistent sound regardless of power conditions. Balanced and single-ended operation allows maximum flexibility for hook-ups with other equipment. Proprietary Krell output and driver transistors assure substantial output current capability. Sales Literature (File size 704K) Krell Current Tunnel Preamplifier The new KCT is at the vanguard of the next generation of Krell components, featuring CAST outputs and a breakthrough circuit design from Krell that delivers the most efficient signal transmission from the input of the preamplifier to its output, termed Krell Current Tunnel topology. This circuitry protects the audio signal from voltage as if the signal is in a tunnel, providing the signal with a sheltered conduit for internal signal transmission in the current domain. At the output stage, CAST technology provides the most accurate signal transfer from one component to the next. As a stereo preamplifier, the KCT delivers state-of-the-art music reproduction to either of two independently selectable zones. Krell's unique Theater ThroughputTM allows the user to connect an outboard audio-video processor, such as the Krell Home Theater Standard, for seamless integration into home theater systems. The KCT is designed for high performance and flexibility, incorporating features that give the forward thinking music lover traditional stereo, multi-room, or home theater system functionality. The visual appearance of the Krell KCT complements the contemporary styling of other Krell Class A components with CAST technology, including the new KPS 28c Krell Playback System, the Full Power Balanced Stereo Amplifiers, and Full Power Balanced Monaural Amplifiers. Highlights The first Krell preamplifier to feature Krell Current Tunnel topology and CAST technology. The first Krell preamplifier to incorporate two zone operation. The KCT provides independent source selection and volume control for zone 2. Multiple inputs and outputs are provided for any high performance audio application. A full complement of features for advanced system control include: One 12 VDC (12 V trigger) input and three 12 VDC outputs, a Krell Link connection, and an RS-232 connector. A sophisticated menu system allows naming inputs, setting volume trim levels, and the selection of balance levels for each input. The IR Program Remote command allows the KCT to teach its remote control commands to a learning remote control. A four line 24 character vacuum fluorescent display provides complete operational information. Sales Literature (File Size 120K) KPS 25sc Krell Playback System The KPS 25sc Krell Playback System provides advanced sound and convenient operaton for digital and analog playback from today's current compact disc format and is designed to be upgraded to address future formats. It combines three carefully matched audio components into a unified whole: a professional-grade compact disc reading mechanism, an advanced digital processor/digital-to-analog converter (DAC), and a reference analog preamplifier. Audiophiles and music lovers understand and embrace this concept for three compelling reasons: performance, simplicity, and upgradability. The performance benefits of the KPS 25sc integration are reduced noise and distortion, improved signal transfer and timing, and better linearity. These three reasons are key to the musical qualities that define advanced sound reproduction: Revelation of musical detail, authentic tonality and timbre, lifelike imaging, and dynamic impact. Highlights Reference Analog Preamplifier - Direct coupled, high bias, pure Class A, complementary analog circuits offer traditional Krell sound quality for unsurpassed playback. - Krell Current Mode circuitry, a faster and more linear method of amplification, operates in a high-speed current domain to deliver wide dynamics and high resolution. - High-resolution volume control has over 65,000 steps of level control, providing more precision than is possible with conventional potentiometers. This advanced volume control employs a discrete R-2R resistive ladder configuration, with steps selected by CMOS analog switches that are microprocessor managed to facilitate adjustable taper and control speed. - Sophisticated switching using digital logic to operate networks of gold contact relays insures crisp, positive switching, with absolute sonic integrity maintained. Advanced Digital Processor/Digital-to-Analog Converter (DAC) - Advanced digital signal processing (DSP) features a Krell-designed digital interpolation-filter system that is built around dual 80MHz Motoral DSP circuits to simulate higher sampling rates and provide more linear signal output to the digital-to-analog converter circuits. - HDCD®1 decoding via Pacific Microsonics PMD 100-decoder/digital filter results in audiophile-grade sound from HDCD®1 encoded compact discs. - Twin dual-converter DAC circuits maximize processing power and eliminate common-mode distortions and data glitches for superior playback from conventional compact discs, HDCD®1 encoded compact discs, and professional AES/EBU recordings. - Circuitry mounted on plug-in cards insures compatibility with future technology. - Master oscillator and clocking system synchronizes all digital circuits and provides accurate jitter-free timing for high resolution and linearity. Professional-grade compact disc reading mechanism - High power neodymium direct-drive motor with oversized drive shaft insures performance and reliability beyond conventional compact disc mechanisms. - Low mass, electrolysed metal disc clamp isolates and damps the compact disc for accurate data recovery. The clamp is finished with an electrolyzing process to insure maximum conductivity and prevent static interference. - Belt-driven laser assembly mechanism and viscous damped suspension eliminates unwanted vibrations and preserves error-free data transfer. Sophisticated Power Supply - Highly efficient, well-regulated power supply insulates audio circuits for consistent performance regardless of line fluctuations or noise. - Three independent power sections consisting of thirteen subsections insure total isolation between analog and digital circuits. - Proprietary TO-3 (metal encased) bipolar transistors manage high current and insure circuit stability. Design and Construction - Modular design allows the KPS 25sc to be upgraded, extending today's high level of performance far into the future. - Massive piston-damped prismatic compact disc mechanism cover automatically activates an electronic shutter that prevents air-borne vibrations and light intrusion during compact disc playback. Controls and Interface - A full complement of digital and analog inputs and outputs, plus special connections for the control of other components make the KPS 25sc the ideal center of an ultra high performance audio system. - Remote control operation includes two unique machined aluminum remote controllers for the functionality and pride of ownership that only Krell provides. A tabletop remote controller provides complete and direct access to all KPS 25sc functions and a hand-held remote controller provides easy operation of basic functions. - Balanced and single-ended operation allows maximum flexibility for hook-ups with other equipment. - Direct access remote control operation allows the KPS 25sc Krell Playback System to be easily operated and provides integration with automated sound systems. - Dual alphanumeric displays, one for compact disc operation and one for preamplifier functions, provide complete operational information. - Front-panel infrared receiver and rear-panel jack for RC-5 input accepts commands from other equipment. In addition, 12 VDC input and output terminals provide automatic on/off signals for other equipment including Krell KAV-Series power amplifiers. Krell Link input and output terminals provide coded commands for automatic on/off control of Krell Full Power Balanced power amplifiers. - Programmable menu system provides acess to secondary functions and lets the user assign descriptive names to inputs. Optional Advanced Output Connections - Unique Krell CAST (Current Audio Signal Transmission) output connections operate in the high-speed current domain to deliver wide dynamics and high resolution to CAST-equipped power amplifiers. Krell CAST is a faster and more linear method of signal transfer. Theater Throughput mode provides convenient home theater system integration with surround sound processors. Sales Literature (File Size 448K) KPS 28c Compact Disc Player Continuing the rich Krell tradition of high performance compact disc playback systems, the new KPS 28c features CAST outputs and advanced digital-to-analog converters. Exemplary audio performance, refined styling, and robust construction make the versatile Krell KPS 28c the ideal compact disc player for the Krell owner who wants to take advantage of CAST technology and the serious music lover who wants a superior sounding compact disc player. Highlights CAST output circuitry for unparalleled sound reproduction and the most accurate signal transfer between analog components Four 24-bit Digital-to-Analog converters Traditional Class A, direct coupled Krell Current Mode output circuitry HDCD®1 decoding Rigid disk clamping laser mechanism 12 VDC (12 V trigger) output Sales Literature (File Size 140K) KPE Reference Phono Preamplifier Music lovers will appreciate the fine details, striking bass performance, and spacious sound stage provided by the KPE Reference Phono Preamplifier. It is designed specifically for audiophiles who use moving coil cartridges and provides exceptional LP record playback. Highlights Composite circuitry applies dual cascaded amplification levels to provide high gain (76dB) with low noise (-80dB) to create astonishing imaging and the high resolution of low-level details. Selectable gain level from 58 to 76dB gives user flexibility and accommodates the most exotic moving coil phono cartridges. Mu-metal shielded circuitry cancels radio frequency interference (RFI) and electro-magnetic interference (EMI) to insure optimum performance regardless of location. Passive RIAA equalization provides precise and phase-correct frequency response. The KPE external power supply combined with the KPE Reference Phono Preamplifier becomes a complete stand alone phono system. A circuit board version is available to equip the Krell KRC-HR preamplifier with phono capabilities. KPE Standard Phono Preamplifier Music lovers will appreciate the fine details, striking bass performance, and spacious sound stage provided by the KPE Standard Phono Preamplifier. It is designed specifically for audiophiles who want the flexibility to use any type of phono cartridge. The KPE Standard Phono Preamplifier accommodates moving coil and moving magnet phono cartridges. Highlights Composite circuitry applies dual cascaded amplification levels to provide high gain (64.5dB) with low noise (-71dB for moving coil and -89dB for moving magnet) to create astonishing imaging and the high resolution of low-level details. A wide range of impedance selections allows the user to select precise cartridge to phono preamplifier matching. Mu-metal shielded circuitry cancels radio frequency interference (RFI) and electro-magnetic interference (EMI) to insure optimum performance regardless of location. Passive RIAA equalization provides precise and phase-correct frequency response. The KPE external power supply combined with the KPE Standard Phono Preamplifier becomes a complete stand alone phono system. A circuit board version is available to equip the Krell KRC-HR preamplifier with phono capabilities. KBX Balanced Crossover The KBX Balanced (two-channel) Crossover is a fully active signal distribution network that divides the audible spectrum into discrete frequency channels. It can be configured to accommodate any system designer's needs. Highlights The KBX can be customized to any frequency, slope, and equalization curve for unlimited speaker system design flexibility. An emulation plug-in card is programmed with crossover frequency, slope, and equalization information. It can be reprogrammed to accommodate future system requirements and provide complete system flexibility. The KBX is performance-matched to other Krell Reference components for seamless insertion between Krell preamplifiers and Krell power amplifiers. The included remote power supply makes KBX placement easy and versatile. KBX Application Chart Speaker System Configuration (common terminology) KBX Application Channels of Amplification Required Two-way (BI-amplification) 1 KBX Four (4) Three-way (TRI-amplification) 2 KBX in series Six (6) Four-way (QUAD-amplification) 3 KBX in series Eight (8)

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