Conrad Johnson Amplifiers
Each
conrad-johnson component is patiently and carefully hand assembled,
then individually inspected and its performance verified by an
experienced audio technician. Our confidence in these components is
reflected in the three year limited warranty covering labor and parts
except vacuum tubes. Service is a top priority at conrad-johnson. In
the event that a product does require service, it will be handled
promptly and efficiently.
Classic Vacuum-Tube Stereo Amplifiers
The conrad-johnson design team is committed to adapting the advances from our state-of-the-art pursuits to more affordable offerings accessible to a wider range of music lovers.
This resolve is clearly evident in our new range of Classic amplifiers. Borrowing heavily on the technology of our flagship ART amplifier, the Classic amplifiers preserve the distinctive tonal character of individual instruments and voices, with each clearly located within the overall acoustical environment of the original recording. Musical transients are reproduced with realistic impact, but without artificial enhancement. Like their more costly siblings, the Classic amplifiers capture the emotional impact of the live event, never getting between the listener and the musical performance.
There really is no mystery to our chosen path to outstanding musical performance: best results come from simple circuits executed with quality parts.
The circuit design for the Classic amplifiers is about as simple as possible, employing just seven vacuum tubes in the Classic Sixty-Two. Single-ended triode voltage gain and inverter stages are coupled to an output stage comprised of a single pair of ultra-linear operated EL34 tubes for each channel. The Classic One-Twenty adds a second pair of output tubes to each channel to achieve twice the output power. Simple but highly effective discrete voltage regulators supply rock-solid stable DC voltage to the critical voltage gain and inverter stages. And speaking of simple, maintenance of the Classic amplifiers could hardly be easier: the owner need only make a simple bias adjustment using the built in bias indicators when installing fresh output tubes.
The use of premium quality component parts is the other half of the conrad-johnson recipe for superior musicality.
In this area as well, the Classic amplifiers are leaders in their class. Precision, metal-film resistors yield low noise performance for greatest clarity. Polypropylene and polystyrene capacitors, chosen to achieve a high degree of temporal accuracy, are specified for both the audio cir¬cuits and the regulated plate voltage supplies for the input and inverter stages. The result is an exceptional range of dynamics – reproducing both subtle variations in level as well as dramatic loud crescendos. Our proprietary trans-spectral wide-bandwidth output transformers contribute importantly to the extended, “airy” highs that help distinguish the Classic amplifiers from ordinary tube amplifiers.
The base model Classic amplifiers offer an ideal introduction to the joys of modern tube amplifiers, while the ease of use, low maintenance costs, and reliability will be a revelation for those who have only experienced “entry-level” tube gear.
Those who wish to take the experience a step further will want to investigate the upgraded Classic Sixty-Two SE and Classic One-Twenty SE amplifiers. These special edition versions upgrade the output tubes to KT120s and incorporate CJD Teflon Capacitors and ultra high-performance metal foil resistors in strategic applications in the circuit. Any of the Classic amplifier models are sure to rekindle your passion for enjoying great music in your home.
This resolve is clearly evident in our new range of Classic amplifiers. Borrowing heavily on the technology of our flagship ART amplifier, the Classic amplifiers preserve the distinctive tonal character of individual instruments and voices, with each clearly located within the overall acoustical environment of the original recording. Musical transients are reproduced with realistic impact, but without artificial enhancement. Like their more costly siblings, the Classic amplifiers capture the emotional impact of the live event, never getting between the listener and the musical performance.
There really is no mystery to our chosen path to outstanding musical performance: best results come from simple circuits executed with quality parts.
The circuit design for the Classic amplifiers is about as simple as possible, employing just seven vacuum tubes in the Classic Sixty-Two. Single-ended triode voltage gain and inverter stages are coupled to an output stage comprised of a single pair of ultra-linear operated EL34 tubes for each channel. The Classic One-Twenty adds a second pair of output tubes to each channel to achieve twice the output power. Simple but highly effective discrete voltage regulators supply rock-solid stable DC voltage to the critical voltage gain and inverter stages. And speaking of simple, maintenance of the Classic amplifiers could hardly be easier: the owner need only make a simple bias adjustment using the built in bias indicators when installing fresh output tubes.
The use of premium quality component parts is the other half of the conrad-johnson recipe for superior musicality.
In this area as well, the Classic amplifiers are leaders in their class. Precision, metal-film resistors yield low noise performance for greatest clarity. Polypropylene and polystyrene capacitors, chosen to achieve a high degree of temporal accuracy, are specified for both the audio cir¬cuits and the regulated plate voltage supplies for the input and inverter stages. The result is an exceptional range of dynamics – reproducing both subtle variations in level as well as dramatic loud crescendos. Our proprietary trans-spectral wide-bandwidth output transformers contribute importantly to the extended, “airy” highs that help distinguish the Classic amplifiers from ordinary tube amplifiers.
The base model Classic amplifiers offer an ideal introduction to the joys of modern tube amplifiers, while the ease of use, low maintenance costs, and reliability will be a revelation for those who have only experienced “entry-level” tube gear.
Those who wish to take the experience a step further will want to investigate the upgraded Classic Sixty-Two SE and Classic One-Twenty SE amplifiers. These special edition versions upgrade the output tubes to KT120s and incorporate CJD Teflon Capacitors and ultra high-performance metal foil resistors in strategic applications in the circuit. Any of the Classic amplifier models are sure to rekindle your passion for enjoying great music in your home.
Announcing the New CAV45 Stereo Control Amplifier
The control amplifier represents a distinctly different approach to high-performance home audio. In many ways it is the ultimate embodiment of our design philosophy that simple circuits yield best results.Similar in function to an integrated amplifier, a control amplifier offers the significant potential improvement of eliminating extra connections, external cabling, and inter-device connection considerations that limit conventional audio systems. But the control amplifier also eliminates an entire stage of audio circuitry (the line stage) and its inherent colorations.
The CAV45 is a vacuum-tube control amplifier. Its audio circuit is similar to our highly regarded Classic Sixty power amplifier, with triode voltage gain and phase inverter stages and an output stage comprised of a pair of EL34s per channel operated in ultralinear mode to produce 45 watts per channel.
The use of carefully selected, high-quality parts enables the CAV45 to properly exploit the dramatic potential of a control amplifier to enhance the immediacy of musical experience afforded by fine recordings. All resistors in the audio circuits and related power supplies are precision metal film types. With the exception of the large power supply reservoir capacitors (which are specially chosen electrolytic capacitors bypassed by polypropylenes), all capacitors in these circuits use polystyrene and polypropylene dielectrics.
This execution of minimalist circuitry with quality parts result in a control amplifier that is notable for its resolution of subtle dynamic shadings and palpable imaging, for a natural harmonic tonality, and extraordinary resolution.
The CAV45 is a vacuum-tube control amplifier. Its audio circuit is similar to our highly regarded Classic Sixty power amplifier, with triode voltage gain and phase inverter stages and an output stage comprised of a pair of EL34s per channel operated in ultralinear mode to produce 45 watts per channel.
The use of carefully selected, high-quality parts enables the CAV45 to properly exploit the dramatic potential of a control amplifier to enhance the immediacy of musical experience afforded by fine recordings. All resistors in the audio circuits and related power supplies are precision metal film types. With the exception of the large power supply reservoir capacitors (which are specially chosen electrolytic capacitors bypassed by polypropylenes), all capacitors in these circuits use polystyrene and polypropylene dielectrics.
This execution of minimalist circuitry with quality parts result in a control amplifier that is notable for its resolution of subtle dynamic shadings and palpable imaging, for a natural harmonic tonality, and extraordinary resolution.
CA 150 Control Amplifier
Conrad-Johnson is pleased to announce the availability of the new conrad-johnson CA150 control amplifier – a power amplifier with level control and source selectors. A control amplifier is identical in function to an integrated amplifier, but without the additional distortions that would be inherent in a superfluous line-stage. Like an integrated amplifier, a control amplifier also eliminates the colorations of preamplifier to amplifier interconnect cables. The CA150 combines the circuitry of our popular MF2275 power amplifier with source selector circuits and a Burr-Brown precision level control.
With full remote control of all functions, and 7 line level inputs, including an EPL (tape) loop and Theater loop, the CA150 offers all the flexibility of our separate line-stage preamplifiers. And with rated output of 135 watts/channel, the CA150 has ample power for the majority of speaker systems.
With full remote control of all functions, and 7 line level inputs, including an EPL (tape) loop and Theater loop, the CA150 offers all the flexibility of our separate line-stage preamplifiers. And with rated output of 135 watts/channel, the CA150 has ample power for the majority of speaker systems.
ART and ARTsa Vacuum-Tube Power Amplifiers
The limited edition
ART Amplifier is designed to be a reference amplifier for the use of
industry professionals as well as dedicated audiophiles. Like its
companion GAT Preamplifier, the ART Amplifier will be offered in an
edition of just 250 units (125 pairs) to be sold through selected
conrad-johnson dealers and distributors. Those who do not need the
prodigious 275 watt power delivered by the mighty ART mono-blocks will
want to consider the ARTsa Stereo Amplifier. Nearly identical
cosmetically (one more tube in the front), it is exactly an ART
amplifier divided into two channels, each producing a solid 140 watts.
At conrad-johnson, our approach to circuit design is predicated on the principle that the surest path to both state-of-the-art musicality and exceptional reliability is simple circuits constructed of the finest available parts. These ART amplifiers exemplify this basic principle. The audio circuit has just three elements, each as simple as possible, and each essential to the operation of the amplifier. A voltage gain amplifier (a single triode) is direct-coupled to a cathode coupled phase inverter (each phase handled by a single triode), which in turn drives the output stage. For the ART mono-blocks, four pairs of KT120 output tubes, chosen for their musical accuracy, high power, and reliability, endow this amplifier with a muscular 275 watt output rating. For the ARTsa, two pairs of KT120 output tubes in each channel produce 140 watts of power per channel. A small amount (about 12 dB) of loop negative feedback reduces distortion and achieves a sufficiently high damping factor to control the reactive load typically presented by high-performance loudspeaker systems. To assure continued peak performance, the owner need only make a simple bias adjustment when new tubes are installed. Built in LED bias indicators allow the user to make this adjustment using only the supplied screwdriver.
Separate, low impedance, discrete dc power supply regulators are provided for the input and phase-inverter stages, thoroughly isolating these stages from the power demands of the output stage. These power supplies are designed to maintain a rock solid supply at all audio frequencies.
Component parts contribute importantly to the sonic performance of any circuit design. The ART amplifiers maintain the exacting quality standards for which conrad-johnson is internationally known. Resistors are precision laser-trimmed metal foil types. Coupling capacitors are the new Teflon CJD caps, while the power supplies use large value polypropylene capacitors in parallel with CJD Teflons. There are no electrolytic capacitors in the audio circuits or in the related power supplies. Proprietary wide-bandwidth output transformers contribute to excellent high frequency performance. Even the machined gold plated OFC connectors and the internal wiring have been carefully selected for optimal sonic performance. Attention to every detail enable us to extract the full potential from our circuit designs and ensures that our products will perform to this potential for years to come. The ART and ARTsa amplifiers are built without compromise to achieve a new standard in musical performance, and they are built to last.
At conrad-johnson, our approach to circuit design is predicated on the principle that the surest path to both state-of-the-art musicality and exceptional reliability is simple circuits constructed of the finest available parts. These ART amplifiers exemplify this basic principle. The audio circuit has just three elements, each as simple as possible, and each essential to the operation of the amplifier. A voltage gain amplifier (a single triode) is direct-coupled to a cathode coupled phase inverter (each phase handled by a single triode), which in turn drives the output stage. For the ART mono-blocks, four pairs of KT120 output tubes, chosen for their musical accuracy, high power, and reliability, endow this amplifier with a muscular 275 watt output rating. For the ARTsa, two pairs of KT120 output tubes in each channel produce 140 watts of power per channel. A small amount (about 12 dB) of loop negative feedback reduces distortion and achieves a sufficiently high damping factor to control the reactive load typically presented by high-performance loudspeaker systems. To assure continued peak performance, the owner need only make a simple bias adjustment when new tubes are installed. Built in LED bias indicators allow the user to make this adjustment using only the supplied screwdriver.
Separate, low impedance, discrete dc power supply regulators are provided for the input and phase-inverter stages, thoroughly isolating these stages from the power demands of the output stage. These power supplies are designed to maintain a rock solid supply at all audio frequencies.
Component parts contribute importantly to the sonic performance of any circuit design. The ART amplifiers maintain the exacting quality standards for which conrad-johnson is internationally known. Resistors are precision laser-trimmed metal foil types. Coupling capacitors are the new Teflon CJD caps, while the power supplies use large value polypropylene capacitors in parallel with CJD Teflons. There are no electrolytic capacitors in the audio circuits or in the related power supplies. Proprietary wide-bandwidth output transformers contribute to excellent high frequency performance. Even the machined gold plated OFC connectors and the internal wiring have been carefully selected for optimal sonic performance. Attention to every detail enable us to extract the full potential from our circuit designs and ensures that our products will perform to this potential for years to come. The ART and ARTsa amplifiers are built without compromise to achieve a new standard in musical performance, and they are built to last.
MF2550 and MF2275 Solid State Amplifiers
These latest solid-state amplifiers, the MF2550 and MF2275, nicely embody this approach.
Differing primarily in power output rating, these amplifiers share a common circuit design. High voltage FETS permit highly linear operation of the critical first voltage gain stage, while bi-polar transistors are used to configure an output stage with low output impedance to deliver maximum current to reactive speaker loads.
Linear operation of the audio circuit requires a power supply designed to maintain absolutely fixed operating voltages while meeting current demands that fluctuate rapidly with the music itself. This imposes on the power supply similar design and component choice requirements as on the audio circuit itself. These amplifiers feature discrete dc regulators to power the critical voltage gain stage. The power supplies and grounds for the input and output stages are run by separate power transformer windings to isolate the input stage from the effects of the substantial current flows required in the output stage.
Differing primarily in power output rating, these amplifiers share a common circuit design. High voltage FETS permit highly linear operation of the critical first voltage gain stage, while bi-polar transistors are used to configure an output stage with low output impedance to deliver maximum current to reactive speaker loads.
Linear operation of the audio circuit requires a power supply designed to maintain absolutely fixed operating voltages while meeting current demands that fluctuate rapidly with the music itself. This imposes on the power supply similar design and component choice requirements as on the audio circuit itself. These amplifiers feature discrete dc regulators to power the critical voltage gain stage. The power supplies and grounds for the input and output stages are run by separate power transformer windings to isolate the input stage from the effects of the substantial current flows required in the output stage.
LP125sa Vacuum-Tube Stereo Power Amplifier
The LP125sa Stereo
Amplifier and LP260m mono-block are the latest in the highly regarded
series of conrad-johnson vacuum-tube power amplifiers. The LP125sa
offers a compelling combination of the audio excellence one expects from
conrad-johnson, the convenience of a single stereo chassis, and, at 125
watts per channel, sufficient power for the majority of high-end
speaker systems. Those with more demanding speaker systems will want to
turn to the LP260m mono-block powerhouse, rated at 270 watts. Both
amplifiers are capable of capturing the delicate textures and subtle
nuances of live music while maintaining control with the authority that
comes with ample power.
Nearly identical in
both models, the audio circuit consists of three stages. The input
signal is amplified by a single-ended triode amplifier designed for wide
band width. The signal is then direct coupled to a cathode coupled
phase-inverter. This high cur rent, triode phase-inverter stage provides
a bal anced, low impedance drive to the output stage. Output power is
developed by KT120 power tubes (two pairs per channel in the LP125sa,
four pairs in the LP260m), chosen for their excellent sonic character,
high power capability, and reliability. The output tubes are operated in
ultralinear configuration which offers a desir able combination of high
power and low distortion. Massive output transformers with intricately
interleaved wind ings afford extended bandpass and high phase
linearity. A small amount (about 12 dB) of loop negative feedback
reduces distortion and achieves a sufficiently high damping factor to
control reactive loudspeaker systems.
Power supply design is every bit as critical to the performance of an audio component as the audio circuit itself. Separate, low impedance, discrete dc power supply regulators are provided for the input and phase-inverter stages, preventing the output stage from modulating these stages through the power supply.
These amplifiers require no complicated adjustments or specialized equipment to main tain. To assure continued peak performance, the owner need only make a simple bias adjustment when new tubes are installed. Built in LED bias indicators allow the user to make this adjustment using only the supplied bias adjustment tool.
Power supply design is every bit as critical to the performance of an audio component as the audio circuit itself. Separate, low impedance, discrete dc power supply regulators are provided for the input and phase-inverter stages, preventing the output stage from modulating these stages through the power supply.
These amplifiers require no complicated adjustments or specialized equipment to main tain. To assure continued peak performance, the owner need only make a simple bias adjustment when new tubes are installed. Built in LED bias indicators allow the user to make this adjustment using only the supplied bias adjustment tool.
LP260M Vacuum-Tube Mono Power Amplifier
At conrad-johnson we
are keenly aware that component parts contribute importantly to the
sonic performance of any circuit design. As expected for conrad-johnson
products, the LP125sa and LP260m amplifiers set uncommonly high quality
standards. Resistors are precision metal film types. All audio-circuit
capacitors, as well as all capacitors in the regulated power supplies
are polypropylene and polystyrene. Proprietary wide-bandwidth output
transformers contribute to excellent high frequency performance. Even
the gold plated connectors and the internal wiring have been carefully
selected for optimal sonic performance. These amplifiers offer tube
performance that "just sounds right". Those who wish to take the
experience a step further will want to investigate the upgraded LP125sa+
and LP260mSE which incorporate CJD Teflon Capacitors and ultra
high-performance metal foil resistors in strategic applications in the
circuit. Any of these models is sure to rekindle your passion for
enjoying great music in your home.
Classic Sixty Vacuum-Tube Amplifier
Tasked with developing the most cost effective amplifier that we could
build, consistent with our standards of quality of construction and
performance, the conrad-johnson design team turned to our flagship
product for inspiration. Borrowing heavily on the technology of its big
brother, the ART amplifier, the Classic Sixty preserves the
distinctive tonal character of individual instruments and voices, with
each clearly located within the overall acoustical environment of the
original recording. Musical transients are reproduced with realistic
impact, but without artificial enhancement. Like its more costly
siblings, the Classic Sixty captures the emotional impact of the live event, never getting between the listener and the musical performance.
There really is no mystery to the basis for outstanding musical performance: best results come from simple circuits executed with quality parts. The Classic Sixty
amplifier circuit design is about as simple as possible, employing just
seven vacuum-tubes. Single-ended triode voltage gain and inverter
stages are coupled to an output stage comprised of a single pair of
ultra-linear operated EL34 tubes for each channel. As it is critically
important that the DC voltage supplied to the gain stages be absolutely
rock-solid stable, these voltages are provided by simple but highly
effective discrete voltage regulators. And speaking of simple,
maintenance of the Classic Sixty could hardly be easier: the
owner need only make a simple bias adjustment using the built in bias
indicators when installing fresh output tubes.
The use of premium quality component parts is the other half of our underlying design mandate. In this area as well, the Classic Sixty is a leader in its class. Precision, metal-film resistors yield low noise performance for greatest clarity. Polypropylene and polystyrene capacitors, chosen to achieve a high degree of temporal accuracy, are specified for both the audio circuits and the regulated plate voltage supplies for the input and inverter stages. The result is an exceptional range of dynamics – reproducing both subtle variations in level as well as dramatic loud crescendos. Our proprietary trans-spectral wide-bandwidth output transformers contribute importantly to the extended, "airy" highs that help distinguish the Classic Sixty from ordinary tubed amplifiers.
The use of premium quality component parts is the other half of our underlying design mandate. In this area as well, the Classic Sixty is a leader in its class. Precision, metal-film resistors yield low noise performance for greatest clarity. Polypropylene and polystyrene capacitors, chosen to achieve a high degree of temporal accuracy, are specified for both the audio circuits and the regulated plate voltage supplies for the input and inverter stages. The result is an exceptional range of dynamics – reproducing both subtle variations in level as well as dramatic loud crescendos. Our proprietary trans-spectral wide-bandwidth output transformers contribute importantly to the extended, "airy" highs that help distinguish the Classic Sixty from ordinary tubed amplifiers.
The Classic Sixty offers an ideal introduction to the joys of
modern tube amplifiers, while the ease of use, low maintenance costs,
and reliability will be a revelation for those who have only experienced
"entry-level" tube gear. Those who wish to take the experience a step
further will want to investigate the upgraded Classic Sixty SE,
which upgrades the output tubes to KT120s and incorporates CJD Teflon
Capacitors and ultra high-performance metal foil resistors in strategic
applications in the circuit. Either model is sure to rekindle your
passion for enjoying great music in your home.
MF2550 and MF2275 Solid State Amplifiers
These latest solid-state amplifiers, the MF2550 and MF2275, nicely embody this approach. Differing primarily in power output rating, these amplifiers share a common circuit design. High voltage FETS permit highly linear operation of the critical first voltage gain stage, while bi-polar transistors are used to configure an output stage with low output impedance to deliver maximum current to reactive speaker loads.
Linear operation of the audio circuit requires a power supply designed to maintain absolutely fixed operating voltages while meeting current demands that fluctuate rapidly with the music itself. This imposes on the power supply similar design and component choice requirements as on the audio circuit itself. These amplifiers feature discrete dc regulators to power the critical voltage gain stage. The power supplies and grounds for the input and output stages are run by separate power transformer windings to isolate the input stage from the effects of the substantial current flows required in the output stage.
Linear operation of the audio circuit requires a power supply designed to maintain absolutely fixed operating voltages while meeting current demands that fluctuate rapidly with the music itself. This imposes on the power supply similar design and component choice requirements as on the audio circuit itself. These amplifiers feature discrete dc regulators to power the critical voltage gain stage. The power supplies and grounds for the input and output stages are run by separate power transformer windings to isolate the input stage from the effects of the substantial current flows required in the output stage.
