Audio Research PH3
Silver Face Plate
- Mint Condition
- Original Box
- New 6922 EH Gold Pins
- Original Owner's Manual
A mint condition all tubed Phono Stage from Audio Research with 3 x 6922 valves and with a rich sound.
The PH3 is a Phono Pre-Amplification stage intended for use with an active line-level stereo preamplifier. Fully single-ended from input to output, the PH3 uses a combination of J-FET input stage technology (for low inherent circuit noise) and class A operation vacuum-tube gain via three 6922 twin triodes. Total gain of the PH3 is 54 dB (non-adjustable). Used with typical line preamplifiers having 12 to 18 dB of gain, the PH3 is suitable for Phono Cartridges having .25 mV output or higher. Input impedance is factory-set at 47K ohms, and input capacitance at 90 pF. For optimal matching to moving-coil and moving-magnet Phono Cartridges, both input impedance and input capacitance may be adjusted via simple resistor and capacitor changes.
On the rear panel, the PH3 provides one pair of gold-plated, audiophile-grade single-ended connectors for L & R inputs, and one pair for outputs. High-quality single-ended interconnects such as Audio Research Litz Link 2 brand are strongly recommended for best sonic performance with the PH3.
±.15dB of RIAA, 10Hz to 60kHz; 3dB points below 0.5Hz and above 400kHz
Less than .005% at .50V RMS 1kHz output
Noise & hum
0.1µV equivalent input noise, IHF weighted, shorted input (80 dB below 1mV 1kHz input)
54dB at 1kHz (MC & MM compatible)
47K ohms and 90pF Unbalanced. (Provisions for any value below 47K ohms or added input capacitance for matching certain magnetic cartridges.)
200 ohms Unbalanced. Recommended load 50K-100K ohms and 100pF. (10K ohms minimum and 2000pF maximum.)
60mV RMS at 1kHz (240 mV RMS at 10kHz)
.50V RMS 10Hz to 60kHz, 100K ohm load (output capability is 30V RMS output at 1/2% THD at 1kHz).
Electronically-regulated low and high voltage supplies. Line regulation better than .01%
(3) 6922/E88cc dual triodes
100-135VAC 60Hz (200-270VAC 50/60Hz) 28 watts maximum. Line fuse 0.6A SLO BLO (0.3A SLO BLO 230V)
19" (48 cm) W x 5.25" (13.4 cm) H (standard rack panel) x 10.25" (26 cm) D. Handles extend 1.50" (3.8 cm) forward of front panel. Rear chassis fittings extend .75" (2.2 cm)
10 lbs. (4.5 kg) Net; 19 lbs. (8.6 kg) Shipping.