Inputs
Phono
2 Phono inputs.
The first has selectable resistance and capacitance, while the second is fixed at 47kΩ and 50 pF.
100 mV maximum at 1 kHz, inverse RIAA, warp-proof.
The right channel of each of the two phono inputs is internally adjustable ±2 dB for perfect channel balance.
Line
All line inputs are 50 kΩ in parallel with 330 pF.
Unselected inputs are terminated with 2.2 kΩ.
Maximum input level: 10 V RMS (+20 dBV or +22 dBm).
3 line-level inputs.
2 tape monitor loops.
1 external processor loop, for a total of six line-level and two phono inputs!
Gain, Polarity and Volume Control
18 dB maximum gain from line inputs.
Phono preamp gain: 36.5 dB at 1 kHz: 5 mV for 2 V output, 1.25 mV for 0.5 V output.
All outputs are non-inverting.
Volume control rated to track left-right to within 1 dB over the entire range. I’m impressed: this is a very important parameter, and this is the only preamp I’ve ever seen which bothers to specify it.
The multiwiper 10 kΩ volume control has 32 clicks, or 31 intervals, at 10º per click, or room for 36 clicks in 360.º
The volume control uses individually trimmed thick-film resistors to ensure precise channel-to-channel tracking.
Outputs
Two MAIN outputs, fed in parallel. Provisions on the circuit board to allow your technician to insert a fixed resistive pad in the path of the MAIN 2 output if this optimizes the gain structure for your power amplifier.
330 Ω source impedance, 5 kΩ/3,000 pF maximum load.
Two tape outputs: 100 Ω source impedance, 10 kΩ/1,000 pF maximum load.
One external processor output.
One ¼” headphone output from a separate amplifier.
Output Levels
2 V RMS for rated specifications.
7 V RMS maximum undistorted.
If loaded with 2 kΩ, 3 V RMS maximum.
10 V RMS from the separate headphone amplifier.
Frequency Response
20 – 20,000 Hz ±0.5 dB, with ultrasonic and ultrasonic filters active.
RIAA EQ ±0.5 dB 30 – 15,000 Hz.
Selectable 15 Hz Infrasonic filter (rear panel switch)
Within 0.5 dB at 20 Hz, -3 dB at 15 Hz and > -30 dB at 5 Hz.
Group delay 4 mS at 50 Hz.
If the filter isn’t selected, the -3 dB point is 8 Hz.
Ultrasonic Filter (automatically engaged when Tone Controls active)
Within 0.5 dB at 20 kHz, -3 dB at 40 kHz, and -18 dB at 100 kHz.
Group delay 7 µS.
Interchannel delay: < 0.5 µS. (the limit of audibility is 10 µS.)
When the tone controls are defeated, the -3 dB point is 150 kHz.
High Filter (only active with Tone Controls selected)
-3 dB at 8 kHz.
Distortion
Less than 0.01% THD at rated output (2V) and lower.
Less than 0.01 % SMPTE intermodulation distortion (60/7k Hz 4:1) at rated output (2V) and lower.
Less than 0.005% DFD with 19 kHz and 20 kHz mixed 1:1, at rated output (2V) and lower.
Less than 0.006% (-84 dB) TIM with 3.18 kHz square and 15 kHz sine mixed 4:1 peak-to-peak, low-pass filtered at 6 dB/octave at 100 kHz, at rated output (2V) and lower.
Noise (all A-weighted RMS)
Phono, measured with standard IHF cartridge
-74 dB down from 5 mV RMS at 1 kHz. Typically -76 dB.
Noise figure: 4 dB, 2 dB typical.
-90 dBV output noise with volume control at -20 dB.
Line
-106 dBV equivalent input noise.
-95 dBV output noise with volume control at minimum.
-95 dBV output noise with volume control at -20 dB.
Hum
Typically equal to or less than the wideband noise spectrum.
Crosstalk
< -65 dB at 1 kHz.
< -45 dB at 20 kHz.
< -90 dB from unselected inputs.
When tested, feedthrough from unselected inputs was inaudible.
Power
120V AC, 50-60 Hz. (240V AC with internal wiring change)
95-135 V AC OK. Below 95 V AC won’t trigger the unmute relay. (190-270 V AC at 240 V setting.)
Rated less than 15 W power consumption.
Rated 100 mA RMS current consumption at 120V AC.
125 mA (1/8 A) internal slo-blo pigtail fuse.
I measure 9 W power consumption.
10 foot unpolarized power cord, but oddly the accessory outlets are polarized.
Two unswitched and three switched outlets, rated 1kilowatt maximum.
Size
15.04 x 3.30 x 9.32 inches (382 x 83.8 x 236.7 mm), WHD overall.
Weight
10.5 pounds (4.8 kg).
12 pounds (5.4 kg), packed.
