audio research
SP-2

Description
Tube stereo preamplifier. Generally marked 'Electronic Industries'

Introduced
1969/1970 ?

Discontinued
?

Revisions
SP-2VT
SP-2SS (FET)
SP-2A
SP-2B (?)
SP-2C

Options
-

MSRP (US new retail)
$395 (SP-2VT)
$495 (SP-2SS)
$550 (SP-2C)

Specifications

Frequency response Aux and tuner inputs: ±1 dB 20 Hz to 20 kHz
  Magnetic phono input: ±1 dB of RIAA curve
Magnetic tape input: ±1 dB of Ampex Playback curve
Distortion (THD) Less than .01% at 5 Volts RMS output 1 kHz on either aux or magnetic phono input, gain max, high impedance.
  Impulse distortion: Essentially none, 30 Hz to 15 kHz
Noise & hum Aux: 90 dB below 1 Volt input
  Mag: 60 dB below 10 mVolt input
Gain Aux: 20 dB (voltage gain of 10X)
Mag: 54 dB (voltage gain of 500X)
Input impedance Aux: 500 kOhms
Mag: 50 kOhms
Output impedance  
Output polarity  
Maximum inputs Aux: 50 Volts RMS @ 1 kHz
Mag: 750 mVolts RMS @ 1 kHz
Rated outputs Maximum output level: At least 30 Volts RMS 1 kHz into high impedance.
Power supplies  
Tube complement (10) 12AX7
Power requirements 117V 50/60Hz approximately 30 watts
Other Output load: Up tp 2000pF and down to 10 kOhm for 5 Volts RMS output.
Tone control range: ±15 dB at 20 Hz and 10 kHz
Dimensions Panel: 15 5/8" W x 5" H, overall depth 14 1/2"
Panel mounting cutout: 4 3/4" H x 15 1/4" W
Depth behind panel: 14" (includes cable clearance)
Knob and panel clearance: 1 1/4"
Weight 16 lbs. Net, 19 lbs. Shipping

Reviews

Pictures

Electronic Industries SP-2:

SP-2:

SP-2A:

SP-2C: