Nagra BPS phono preamplifier Fred Kaplan
Even after switching to Krell's integrated amplifier, I've hung on to my Audible Illusions Modulus 3a preamplifier so that I could keep using the latter's moving-coil phono section, designed by John Curl and long lauded as the model's strong suit. But Michael Fremer's review of Nagra's BPS battery-powered phono preamplifier ($2399), in the June 2009 "Analog Corner," stoked my curiosity, so I requested a review sample. Then, midway through listening to the Nagra, I overhauled my analog gear, and so was able to gauge it with stuff old (VPI HW-19 Mk.IV turntable and JMW Memorial tonearm, Clearaudio Victory H cartridge) and new (VPI Classic 'table with updated JMW arm, Lyra Argo i cartridge). The improvement in both setups was substantial.
Michael praised the Nagra BPS's "sharp, clean, exciting transients," its tight, dynamic bass, and its "so clean" highsthough he added that, if linked with dry components, some might find its "upfront" presentation "fatiguing." The BPS, he wrote, emphasized "rhythm and pace" over "harmonic structure and richness," although, he added, "the latter, too, were in good supply."
I agree completely, though I'd upgrade that supply from "good" to "very good." With one LP after another, highs were more pure and extended than I'd ever heard in my rooman effect I'd noticed with other battery-powered preamps (there's no AC like no AC), though never to this extent. And bass lines were tighter and more dynamic as wella surprise.
There was also a spooky absence of noise. Music beamed and wafted from a black-silent backdrop with palpable texture and detail. Trumpets blared, strings purred, drums slammed (except when brushstrokes made them fizz), all with an aliveness I hadn't heard before from my system. I've been listening to high-end analog for a quarter-century now, and only with the insertion of the palm-sized BPSand especially after installing the VPI Classic 'table with Lyra Argo i, which deepened the silence and puritydid I find myself musing, "This is what I've been aiming for all these years."
A few technical matters that Michael didn't bring up: The Nagra sounded good plugged into the AC, but it sounded a lot better when it relied on its 9V battery for power. This was true even when it was plugged into a very good AC power conditioner, the Bybee Reference. Nagra's sales rep, John Quick, suggested keeping the BPS on at all times, but plugged into the wall when not in use, to save the battery.
Also, I second MF's advice to experiment with cartridge loadings. This is easy: Open the chassis, pull out one of the loading plugs, push in another. With MC cartridges, do load something. My review sample was set to 47k ohms, the default mode when no loading plugs are inserted (and the correct position for moving-magnet cartridges); it sounded thin. I found that, with both MC cartridges I used, 200 ohms sounded best.
Set up properly, the Nagra BPS is a delight. Bottom line: I bought the review sample.Fred Kaplan