Lamm LP2 Deluxe phono preamplifier
The dual-mono vacuum-tube Lamm LP2, a single black box featuring switchable moving-magnet (MM) and moving-coil (MC) inputs, is also meant to be heard more than to be seen. The Deluxe edition ($6800), with added damping and high-capacity capacitor bank, weighs more than 40 lbs (22 lbs for the $6300 standard version). Vladimir Lamm's high-current, pureclass-A, zero-feedback design uses two pairs of small, high-transconductance, low-noise, post-WWII Western Electric 417A/5842 tubes originally intended for RF preamplification. The RIAA EQ is passive. The Deluxe power supply uses a 6X4 full-wave rectifier tube, a choke-regulated filter, and 150 joules of energy storage (125 joules in the standard edition). Selectable MC step-up is via a 10x Jensen transformer with a 40 ohm input impedance. The MM input is 47k ohms in parallel with 200pF. High-quality components are used throughout, with the Deluxe edition bypassing some caps with polystyrene, and the build quality is superb.
Though the On/Off switch is located inconveniently in the rear, the LP2 is not meant to be left on. Designed to run relatively hot, it needs adequate ventilation, and sounded its best only after about 30 minutes' warmup. Each unit is burned-in at the factory for 72 hours. The documentation is the most complete and detailed I've seen for a high-end audio product, with unusually complete instructions and full sets of useful specs and graphs. Every expensive high-end product should include such thorough advice.
The LP2 Deluxe was super-quiet in both MM (38dB gain) and MC (58dB) modes. Backgrounds were pitch-black, out of which emerged the subtlest of low-level details and graceful musical textures. In fact, the LP2 competed texturally with the Boulder 2008, and bested the Manley Steelhead in that regard. The Manleystill my reference, and I'm still in love with itcan sometimes sound a bit mechanical on top.
The Rega Exact positively sang through the LP2, as did a high-output Adcom Crosscoil (rebuilt by the Garrott Bros.) into the MM input. But the MM input is more of a utility; few buyers at this price point will be running MM. The 40 ohm input impedance proved a good compromise for most MC cartridges, even for the 3 ohm Lyras (the multi-tap Manley transformer stops at 25 ohms). There was nary a trace of transformer signature to be heard through the MC input; the overall sound was warm, relaxed, and expansive, though free of such cliché'd tube signatures as bloom, overly ripe bass, or softened transients.
A/B comparisons with the Groovenot exactly bright on top itselfindicated that the Lamm's top end was ever so slightly diminished, but not at the expense of transient speed and definition. It reminded me of some of the recent Dynavector cartridges, which many readers rave about to me, but which I find slightly reticent. The Lamm's output impedance was a somewhat high 3.5k ohms, so I went back to John Atkinson's measurements of the Hovland HP-100's input impedance (see Stereophile, November 2000). This was 100k ohms across most of the band and down to a still-high 86k ohms at 20kHz, so I don't think the slight lack of top-end presence was an impedance mismatch (footnote 1).
Bass extension, control, and definition were startlingly good. Not since the Boulder 2008 have I heard the standup bass on the LP of Alison Krauss's New Favorite sound so well-defined. (The Alesis Masterlink was so helpful in making these instantaneous comparisons!) Subtle dynamic scaling was on a par with the Boulder and notably superior to the Connoisseur, which, while maintaining a superb musical grip, seemed to jump more than it flowed, dynamically and rhythmically. The Lamm had great control of the proceedings, but also knew when to let go.
Subtle string textures, reeds, and female voices were positively thrilling, and the size and weight of the entire pictureespecially stage depth extending well behind and in front of the speakerswas particularly impressive. Add that to snap-you-back-in-your-seat dynamics and authoritative decay, and the Lamm became one of a handful of the finest phono sections I've ever heard. Classic Records' 45rpm reissue of the Reiner/CSO edition of Mussorgsky's Pictures at an Exhibition (RCA Living Stereo LSC-2201) never sounded better.Michael Fremer
Footnote 1: Though I asked for 1000 ohm loading, a communications error led to me being sent 100 ohms, which I didn't find out about until after the review was handed in. My comments about the top-end extension was based upon my belief that loading was set at 1000 ohms. Clearly, a 100 ohm load would darken the sonic picture somewhat and better conform to my observations.Michael Fremer