Audio Research SP9 preamplifier JA November 1987
Worried by JGH's findings on the sound of the SP9, I borrowed the unit from him and installed it in my own system, letting it warm up for a total of five days before attempting any listening. It was used first as a conventional preamplifier, taking the output of Linn Troika and Koetsu Red MC cartridges and feeding my Krell KSA-50 power amplifier (which has an input impedance a bit on the low side at 20k ohms), first via 3m of Monster Interlink Reference (total capacitance 450pF), then via 5m of Radio Shack 300 ohm aerial cable (total capacitance 150pF). In a second series of listening tests, the SP9's line stage, set for as near unity gain as possible, was inserted into my Audio Research SP10 II's tape loop via 1m of Siltech 4/24 and 1m of Monster M1000.
Unfortunately, my findings were much as JGH has reported: the sound on initial switch-on was not good, being hard and bright. After the long warm-up, while much better, the SP9 was still brighter and drier than the SP10, with noticeable reductions in both image depth and the "roundness" of the imaging. The added hardness to the sound made music less enjoyable. I sat LA in my listening chair and operated the SP10's tape monitor switch; he, too, heard what JGH had reported concerning the sound of the SP9's line stage.
How important is the SP9's shortfall in absolute sound quality when its affordable price is taken into consideration? Unlike JGH, I don't prefer the signature of the PV5 to that of the '9; both provide a level of sound quality below that required by my expensive tastes. In the context of a simple passive preamplifier, however, the line stage of the SP9 is still not as neutral as I would like, negating to some extent the value of the excellent switching provided.
As a long-term Audio Research fan, I have to admit that the SP9 proved to be a disappointment. How then, does Stereophile explain the discrepancy between its findings and Peter Moncrieff's almost immoderately positive review? I do what audiophiles should always do: be true to what you hear, not to what you think you ought to hear. Meanwhile, we will obtain a second SP9 to investigate the possibility that we had a sub-standard sample. Audition the SP9 with care.—John Atkinson