Tube Preamp Reviews

During the period I was reviewing the Halcro dm10, VTL TL-7.5 Reference, and BAT VK-51 SE preamplifiers, John Atkinson decided it would be enlightening to have me listen to these state-of-the-art contenders in comparison to the venerable Mark Levinson No.32 Reference (reviewed by Jonathan Scull in January 2000). How, we wondered, would the new boys stand up when compared not only with each other, but also with a long-term resident of Class A of "Recommended Components"? So, over the Thanksgiving holiday weekend, I did just that.

All four were auditioned over the course of four days. The solid-state units were warmed up in standby for a minimum of 48 hours prior to being auditioned; the tubed units were allowed one to two hours of warmup and stabilization time before I did any listening. All comparisons were made with the same system: my regular analog rig, the Aesthetix Io Signature phono stage, Esoteric DV-50 universal digital player, Halcro dm58 amplifiers, and Focal-JMlab Nova Utopia Be loudspeakers.

Acoustic Zen Silver Reference cables were used between the Aesthetix and the individual line stages and between line stages and amplifiers. Siltech SQ-110 Classic carried the Esoteric's signal to the line stages, and LS-188 Classic speaker wire fed the Nova Utopia Be's. Shunyata's Hydra 8 was used as the power source for all front-end components. Shunyata's Anaconda power cables supplied the juice to all of the preamplifiers, and an Anaconda Vx did the honors for the Esoteric. Siltech's SPX-30 Classic AC cords were used on the Halcros.

In back-to-back listening sessions, the character of each preamp came into sharper focus. The VTL TL-7.5 Reference's strongest suit remains its complete lack of discernible sonic character. It had a vanishingly minuscule sonic fingerprint and, as noted in my October 2003 review, does everything so well that it is beyond reasonable criticism. There's nothing meaningful I can add to my earlier review comments.

I can feel one of JA's steady, quiet stares directed at me and calling for some conclusions, so I must beg just a bit of forbearance and indulge in a bit of Solomonic baby-splitting. Were I forced to decide which line stage I would opt for (under the threat of having my LP collection incinerated before my eyes should I fail to do so), I would fess up and go for the VTL. It's the finest pure line stage I have heard, barely nipping the Halcro by a few thousandths of a second at the finish line of this Grand Prix. Its supreme neutrality makes it as nearly perfect a reviewer's tool as exists in the audio world. As noted above, when taken strictly as a line stage, the Halcro sounds, to me, the tiniest bit cool, being ever-so-slightly leaner than the VTL.—Paul Bolin