Audio Research D240 Solid State Amplifier
Refined yet powerful solid state amp from Audio Research made right here in America.
This amp is circa 1992, so 29 years as of today.
In overall beautiful cosmetic condition with no significant signs of use.
**Please note that RCA shorting plugs are required to enable Single Ended Operation. If you ask we'll be happy to provide a set with your purchase.
Your purchase also includes the original box.
Click below to add our recommended matching cables from Kimber Kable, all brand new as SkyFi is an official Kimber dealer.
Solid-state stereo amplifier
MSRP (US NEW RETAIL)
$2,995 ($6k in 2021).
120 watts per channel into 8 ohms, 240 watts per channel into 4 ohms
(-3dB points) 8Hz to 60kHz
1.6V RMS for rated putput (25.8dB gain) unbalanced or balanced
150k ohms normal or invert, 300k ohms balanced differential
0.05dB 8 ohm load to open circuit
OVERALL NEGATIVE FEEDBACK
HUM & NOISE
Less than 150 µs RMS (106dB below rated output IHF A-weighted)
POWER SUPPLY ENERGY STORAGE
105-125VAC 60Hz (210-250VAC 50 Hz) 480 watts at rated output (120WPC 8 ohms).
800 watts maximum (240WPC 4 ohms), 140 watts idle
Input Polarity: Non-inverting at normal inputs. Balanced pin 2+.
19" (48 cm) W (standard rack panel) x 5¼" (13.3 cm) H x 11 ⅝" (29.5 cm) D (front panel back). Handles extend 1 and ⅝" (4.1 cm) forward of the front panel. Output connectors extend 1" behind rear panel.
38 lbs. (17.3 kg) Net
49 lbs (22.3 kg) Shipping
The SkyFi Testing Process for Solid State Amplifiers:
We start with a visual inspection of all internal components to make sure there are no signs of stress or aging. Capacitors are checked for telltale sings of bulging or leaking, resistors are checked for signs of overheating or cracking, and transistors are checked for signs of stress or damage.
We then power up the unit carefully and run a simple 1k sine wave while monitoring the output on an oscilloscope for signs of distortion or noise. Finally, we run the amplifier to its full rated power into the appropriate resistive load provided by our Sencore amplifier tester. If there is an issue, it will usually be noticeable at this point. If everything reads clean, we will often test for THD (Total Harmonic Distortion) measured by our Keithley distortion meter, and compare it against the original manufacturers specifications. The amplifier then remains powered on to "burn in" on our test bench for a few hours to make sure there are no heat related issues. If there are balanced inputs available they will be also be tested.
Final testing involves pushing actual music thorough the amplifier. We've learned over time that some issues are only noticeable to a trained ear while listening to familiar source material. Our test bench has reference vintage KEF speakers that we're very familiar with which quickly reveal any discrepancies. Some amplifiers will then move into our listening room where they are tested with our in-house reference speakers of choice.
Yes - Power