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Audio Research SP-4

Stereo Pre Amplifier (1977)

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Audio Research SP-4


The SP-4 preamplifier was designed around the Analog Module which acts as a 'super tube' because it takes the best qualities we see in the vacuum tube much closer to the theoretical ideal.

The SP-4 surpasses our vacuum tube preamplifier in the most important areas. It has increased musical depth and definition with a smoothness that will satisfy any vacuum tube enthusiast.


Frequency response: 5Hz to 100kHz

Total harmonic distortion: 0.005%

Gain: 36dB (MM), 24dB (line)

Signal to noise ratio: 84dB (MM), 95dB (line)

Output: 2V (Pre out), 10V (Pre out Max)

Dimensions: 480 x 210 x 89mm

Weight: 5.5kg

Accessories: walnut veneered oiled finish cabinet

Year: 1976

Price: USD $895 (1976)


instruction/owners manual   English - Ivy Caudieus

4/4A parts list and schematics   English - Ivy Caudieus

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This website is not affiliated with or sponsored by Audio Research. To purchase SP-4 spares or accessories, please contact the company via their website or visit an authorised retailer.