Up for sale is an Audio Research SP-6E tube preamplifier with moving magnet phono stage. It has enough gain to accommodate a medium output moving coil cartridge without the need of a step up transformer or pre-preamplifier.
The E version is the last and the best version of the SP-6 family before the introduction of the SP-8. It is seldom available on the used market.
Preamplifier has been extremely well taken care of, in excellent to near mint cosmetic condition and perfect working order.
This is a consignment piece - cash deal without tax.
Frequency response: High level section: ±0.25 dB, 5Hz to 30kHz, -3dB points below 1Hz and above 100kHz Magnetic phono: ±0.25 dB of RIAA, 30Hz to 40kHz
Harmonic distortion: Less than .01% at 2V RMS output, 20Hz to 20kHz (Typically less than .0002% in midband)
Intermodulation distortion: Less than .002% at 2V RMS output
Gain: Magnetic phono input to tape output: 34dB Magnetic phono input to main output: 60dB High level inputs to tape output: 0dB High level inputs to main output: 26dB
Input impedance: 50k Ohms, all inputs. (Magnetic phono may have any value from 10 ohms to 100k Ohms substituted. Also has provision to add to the 40pf input capacitance for matching certain magnetic cartridges.)
Output impedance: Less than 500 Ohms main output, 100 ohms tape output. Recommended minimum load for maximum audio quality, 20K ohms and .001 uF maximum capacitance.
Maximum inputs: Magnetic phono, 900 mV at 1kHz (3.5V RMS, 10kHz). High level inputs essentially over load-proof.
Rated outputs: 2V RMS 5Hz to 30kHz, all outputs; 60k Ohm load. (Main output capability is 60V RMS output at .5% THD at 1kHz into a 500k Ohm load with 3V RMS high level input.)
Power supplies: Electronically-regulated solid-state supplies. Frequency-compensated high voltage supplies have a total equivalent low frequency stability of greater than 1 farads of capacitance. Line regulation better than .001%.
Noise: High level (1) 250V RMS maximum residual unweighted wide-band noise at main output with gain control minimum (86dB below 5V RMS output). (2) More than 90dB below 1V RMS input (less than 20 µV equivalent input noise).