Hybrid stereo amplifier new
Price: $ 8,500.00 / each
|| Warranty and considerations:
|Warranty Terms (Parts and Labor)
||3 year |
|Free Shipping to the Continental US?
conrad johnson ET250 Stereo Amplifier
The conrad-johnson Enhanced Triode (ET) Amplifiers are power amplifiers
designed to capture the best attributes of both fine vacuum-tube designs and of
the best solid-state designs. The ET250S is a 250-watt per channel stereo power
amplifier, This sophisticated zero-feedback amplifiers offer the refinement of a
vacuum-tube amplifier with the guts and control of a solid-state amplifier.
Zero Feedback. Negative feedback is an engineering technique used to reduce
measured distortion. While feedback does achieve this goal, it also introduces
aberrations in the transient response characteristics of the circuit. We
have found that eliminating loop negative feedback can result in much finer
gradations in dynamic response (micro-dynamics) and more accurate decay on
musical transients. But eliminating negative feedback requires much more care in
the design of the circuits - both in choosing devices and in power-supply
design, and places greater demands on the parts.
The Right Device for the
Job. A power amplifier has two distinctly different functions. First, a voltage
gain stage must increase the amplitude of the input signal by a factor of about
thirty. The distortion characteristics of the amplifier are dominated by this
stage. No device is better suited to accurately amplifying signals at high
amplitude than triode vacuum tubes. For our enhanced triode amplifiers, voltage
gain is provided by a 6922 vacuum tube, selected for its ability to track a high
amplitude signal accurately. Theory and 30 years of experience have taught us
that the voltage gain stage of a power amplifier dominates the sonic character
of the critical mid-range of a power amplifier, and indeed these amplifiers
exhibit the smooth, lucid midrange for which tube amplifiers are so highly
The high amplitude signal produced by the voltage gain stage must then be
efficiently coupled to the loudspeaker system through an output stage to produce
the power and control needed for a musically accurate response – basically to
provide current gain and a low output impedance. High-current bi-polar devices
have been specified for the output stages of these amplifiers, based on their
extremely low output impedance and their ability to handle a great deal of
current. This contributes the fast, weighty bass and seemingly limitless power
reserve that are notable in these amplifiers.
Solid Power Supplies. Rock
solid power supplies are needed to enable the audio circuits to reach their
potential on musical transients. The ET amplifiers feature oversized main
power transformers (so that the circuits are not starved for current), and
massive power storage reservoirs with high-speed capacitor shunts to deliver
quick, even startling transient response. Carefully designed DC voltage
regulators isolate the critical voltage gain stages to prevent demands of the
output stage from modulating the input signal.
Quality Parts. Conrad-Johnson
components are internationally known for the quality of their parts, and the ET
amplifiers are no exception. The audio circuits and their related power supplies
utilize precision low inductance laser-trimmed metal foil resistors. The
circuits employ polypropylene, polystyrene and Teflon capacitors extensively,
except in the main power supply storage, where high-speed electrolytics are used
because of the extremely high capacitance required. Precision-machined
input/output connectors have been carefully selected for optimal sonic
performance. Even the internal wiring is chosen on the basis of its sound
quality in its specific application.
Thoughtful engineering, specification
of top quality component parts, and painstaking care taken in production make
the MET150 and ET250S capable of extraordinary performance in music
reproduction. We invite you to arrange an audition with your conrad-johnson
dealer to confirm for yourself the extraordinary musicality of these
ET250S - 250 Watts per channel
from 20 Hz to 20 KHz at no more than 2 % THD, both channels driven into 8 Ohms,
or 400 watts per channel driven into 4 Ohms.
1.85V to rated power.
Frequency Response (at 10 Watts): 20 Hz to 20 kHz, +/-
Hum and Noise: 104 dB below rated power
Input Impedance: 100
ET250S - 2 x 6922
MET150 - 5 x 6922
ET250S 16.125D x 19W x 7.188H inches
ET250S 65 Lbs.