audio research

Tube phono preamplifier.

From the ARC website

There is good news for analog music lovers worldwide who have been waiting patiently for a Reference Series phono preamplification stage to accompany their Audio Research Reference 1 or 2 line stage. The new Audio Research Reference Phono stage is now available from authorized retailers.

The REF Phono stage is an all-vacuum-tube design. Of the 14-tube total, eleven 6922 twin triodes are used in a unique single-ended signal path. High voltage rectification utilizes a 5AR4 / GZ34, while regulation is accomplished using a 6550C controlled by another 6922.

For the analog music purist, this is the phono stage to make everyone happy! Using chassis construction and dimensions identical to the REF1 and REF2 line stage preamplifiers, the REF Phono makes a perfect companion piece, visually and sonically, to other Audio Research models.

A choice from two sets of inputs -- one (+69 dB gain) for low-output moving coils, the other (+48 dB gain) for high-output moving coils and moving magnet cartridges -- is selected by a rear panel switch. The higher-gain path incorporates a high-purity, multiple-shielded step-up transformer to provide the additional gain. Used with a 12 dB or 18 dB line stage, the REF Phono supplies sufficient gain for virtually any cartridge available.

Cartridge impedance matching is accomplished by the best sonic means available: high-purity resistors soldered to terminal posts inside the chassis. While the REF Phono will normally be factory-set at 47K ohms, separate customer values for both sets of inputs are available at time of order at no extra charge. A resistor kit with special solder is also supplied with each unit.

The REF phono includes additional popular features. The 14-gauge line cord is detachable via the IEC-standard three-pin socket at the rear, allowing custom A.C. cords to be used as desired. Standard front-panel toggle switch controls include Power / On, Operate / Standby, Stereo / Mono and Operate / Mute. The Standby mode, which keeps current running through audio tube heater filaments, will be particularly welcome to those demanding maximum performance without the usual warm-up curve.

With all the relevant features a phono lover needs, yet without the extraneous bells and whistles that would raise cost and inhibit the best sonic performance, the REF Phono is a true thoroughbred in every sense: resolution, frequency response, soundstage focus and musical dynamics are simply beyond what you have experienced before from any phono stage. You will be amazed at how records you haven't heard in years leap to life and become emotionally and musically meaningful again.





MSRP (US new retail)
$6,495. Increased to $6,995 on Feb 5 2001.


Frequency response ± .15dB of RIAA, 10Hz to 60kHz; 3dB points below 1.0Hz and above 250kHz
Distortion (THD) .005% at 0.5V RMS 1kHz output
Noise & hum 0.56uV equivalent input noise, IHF weighted, shorted (Low Gain) input (65 dB below 1mV 1kHz input). 0.055uV equivalent input noise (High Gain) (65dB below 0.1mV 1kHz input)
Gain Selectable 48dB (Low), 69dB (High) at 1kHz (MC & MM compatible)
Input impedance 47K ohms and 180pF Unbalanced (Low Gain), 280 ohms Unbalanced (High Gain). (Provisions for any value below 47K ohms or added input capacitance for matching certain magnetic cartridges.)
Output impedance 200 ohms Unbalanced. Recommended load 50K-100K ohms and 100pF. (10K ohms minimum and 2000pF maximum.)
Maximum inputs 100mV RMS at 1kHz (240 mV RMS at 10kHz)
Rated outputs 0.5V RMS 10Hz to 60kHz, 100K ohm load (output capability is 30V RMS output at 1/2% THD at 1kHz)
Power supplies Electronically-regulated low and high voltage supplies. Line regulation better than .01%
Tube complement (11) 6922/E88CC dual triode, plus (1 each) 5AR4, 6L6GC, 6922 in power supply
Power requirements 100-135VAC 60Hz (200-270VAC 50/60Hz) 120 watts maximum. 50W standby. Line fuse 3A SLO BLO (T2A SLO BLO 230V)
Other Switches: Front (4) Power, Standby, Mono, Mute. Rear (1) Gain
Dimensions 19" (48 cm) W x 7" (17.8 cm) H (standard rack panel) x 15.5" (39.4 cm) D. Handles extend 1.5" (3.8 cm) forward of front panel
Weight 28 lbs. (12.7 kg) Net; 42 lbs. (19.1 kg) Shipping.


Issue 141
Vol. 23 No. 2