Vintage Audio Research D-250 // Stereo Tube Amplifier / Hand-matched tubes / Original Box & Manual

With Perhaps no introduction needed, we're thrilled to present the Audio Research D-250, one of the most widely-praised power amplifiers of all time. The D-250 is a commanding presence. The amplifier is huge, with most of its 138-lb weight coming from massive power and output transformers. With thirty-two hand-matched tubes, delivering a hefty 250 watts of stereo power, this amp was in a class all its own when launched in 1983. Indeed, there are few analogs to this day. Naturally, a component of this caliber deserves the very best, so in addition to a meticulous service and cleaning, our chief engineer put it through a 40-hour critical listening test, and has given this unit the highest marks for musicality.

PRODUCTION 1983 CONDITION 9/10 SERIAL NO. 54230006 ORIG. MSRP $4995 RESTORATION

• Full 30-point service check
• Tested original caps for ESR, replaced any in question
• Recapped signal path with high end Jantzen capacitors (>$600)
• Installed high end power supply capacitors
• Replaced all out-of-spec resistors or power supply transistors
• Inspected and tested all tubes (none over 150 hours of operation)
• Hand-selected 3 new tubes to match gain of originals
• Balanced all tubes
• Cleaned controls, switches, and chassis

SPECS

Type  Tube stereo power amplifier

Power output  240 watts per channel into 16Ω (stereo)

Number of Channels  2

Bridgeable  yes

Frequency response  20Hz to 20kHz

Total harmonic distortion  1%

Damping factor  20

Input sensitivity  0.8V

Signal to noise ratio  90dB

Remote Control  no

Tube Complement  (32 total) 16x 6550 (power output / Sovtek / low gas), 4x 6550 (regulator / Sovtek / low gas), 2x 12AT7 (regulator driver), 4x 6DJ8 (small signal), 4x 7044 (small signal), 2x 6FQ7 (driver)

Dimensions  19"W x 20.75"D

Weight  19"W x 10.5"H x 20.75"D

THE HISTORY OF AUDIO RESEARCH
Audio Research Corporation, affectionately known to fans as ARC, was founded by William Z. Johnson, who began designing custom audio electronics in the early 1950’s and who also operated a specialty audio retail store until the mid-1960’s. Johnson’s efforts almost single-handedly revived vacuum-tube designs at a time...
LINER NOTES

As you might expect from its power rating, the D-250MKIIS is not small; it is not the power amplifier for an audiophile without strong friends. It also is not simply a tube amplifier, it is a 32 -tube amplifier. The D-250MKIIS uses 16 6550s for amplification, four 6550s for electronic regulation, and 12 smaller tubes for the input amp (6DJ8), cross coupler (7044), driver amp (6DJ8), driver cathode follower (7044), and regulator drivers (12AT7).

STOCK NO. 7872506724573