Audio Research Reference 300 MK2 mono amplifiers for sale. Tubes have 500 hours on them.
First, the sonic improvements embodied in the MKII version are nothing short of monumental. The MKII has much more apparent speed than the original, and conveys microdynamics and subtle timbrel details with much higher resolution. Image focus, the sense of body given to notes and voices, and tonal coherence from high frequencies to bass notes are all noticeably better. There is a sense of seamless resolution in the sound stage which, through an appropriate loudspeaker system, is simply mesmerizing with well-recorded material. Finally, the sense of power conveyed by these amplifiers is much more apparent on big dynamic swings -- they have effortless muscle when called for, yet they are capable of amazing delicacy in the next moment.
Power output 280 watts continuous at 16 ohms from 20Hz to 20kHz with less than 1% total harmonic distortion (typically less than .05% at 1 watt). Typical power under average circumstances will be around 290 watts. Maximum power under ideal conditions will be around 300 watts.
Power bandwidth (-3dB points) 12Hz to 100kHz
Frequency response (-3dB points at 1 watt) 0.5Hz to 160 kHz
Input sensitivity 1.75V RMS balanced for rated output. (32dB gain into 16 ohms)
Input impedance 200K ohms balanced
Output taps 1, 2, 4, 8, 16 ohms
Output regulation Approximately 0.8dB 16 ohm load to open circuit
Overall negative feedback 10 dB
Damping factor 11
Hum & noise Less than 0.2mV RMS –110dB below rated output (IHF weighted, input shorted, 16 ohm output)
Power supply energy storage 448 joules
Power requirements 105–125VAC 60Hz (210–250VAC 50Hz) 900 watts at rated output, 1200 watts maximum, 480 watts at idle, 280 watts standby
Tube complement: REFERENCE 300 MKII: (4 matched pairs) 6550C power output, (4) 6H30 triodes, (3) matched 6A57, (2) 6N1P.
The REFERENCE 300 has sufficient bias adjustment range to allow the use of any of the following output tube types: 6550, 6550B, 6550C, KT88, KT90, KT91, KT100.
Dimensions 19" (48.3 cm) W x 10.5" (26.7 cm) H x (23.5" (59.7 cm) D. Handles extend 1.5" (3.8 cm) forward
Weight 132 lbs. (59.9 kg) Net; Shipped in pairs, 410 lbs. (186 kg) per pair
Please communicate through my email address: firstname.lastname@example.org
Can accept PayPal and bank wire.