Anthem AVM 30The most recent of the preamps we tested - high-end separates tend to have a longer model life than receivers do - the Anthem AVM 30 provides 7.1-channel playback of 5.1-channel sound -tracks via some of its THX decoding modes and 5.1- or 6.1-channel playback for stereo sources via Dolby Pro Logic II and DTS Neo:6, respectively. Like the Krell and Parasound preamps, our sample of the Anthem lacked the newer Dolby Pro Logic IIx (DPL IIx) processing, which can generate both 6.1- and 7.1-channel surround from stereo, though a downloadable software upgrade is promised. The AVM 30 produces a similar effect with a proprietary mode, AnthemLogic.

The Anthem is the only preamp here with an AM/FM tuner (6 AM and 18 FM presets). You'll also find a clock and two programmable on/off timers for the main listening area as well as similar timers for each of two remote zones.

SETUP It's not trumpeted in the Anthem promotional literature, but the AVM 30 is one of the very few preamps - or receivers, for that matter - to provide full bass management and speaker-distance compensation for its multichannel analog input. Both functions are vital to getting the best out of DVD-Audio and SACD playback. This alone should promote it to your A list if you want a state-of-the-art system. There's no special setup for these features beyond the usual level and distance settings, though these are made in fine increments of half a decibel and half a foot.

The setup process is uneventful, though you get a few options not found on typical A/V receivers, such as being able to trim the source levels to reduce big differences in volume as you switch between inputs (the Krell and Parasound also allow this) and being able to enter different crossover frequencies for each speaker. During operation, the small front-panel display manages to cram in basic information, like the sound mode and volume setting.

Anthem's Room Resonance Filter, a very important feature that can greatly improve bass performance, is a single-band parametric equalizer with a finely tunable center frequency. It's used during setup to flatten out the single prominent low-frequency room resonance that afflicts most speaker installations. Although Anthem gives detailed instructions, this is best done not by ear but by an automated system, or with a sound-level meter having a flat bass response (which leaves out the otherwise useful and affordable models from RadioShack). A professional installer could help you set up this feature.

On the rear panel, all the inputs are on a black background and all the outputs on white - very simple and effective color-coding - with labels big enough to be legible in somewhat dim lighting. The backlit remote is sensibly laid out, although the multiple functions of some buttons might take a little getting used to.

PERFORMANCE Often, small things - like the fine adjustments Anthem provides for speaker balancing and distance compensation - can make a big difference. The AVM 30's half-foot increments let me dial in rock-solid and very detailed imaging from all multichannel sources, including SACDs and DVD-Audio discs, and all types of music, from soundtracks to operas (try the Decca SACD of Puccini's La Bohème). While the AVM 30's basic surround processing didn't sound any different from the same modes employed by the other preamps, the overall sound quality in our room was often superior due to the greater degree of setup control it provides.

The AVM 30's sonic capabilities and mix of features already place it among the front rank of top-performance preamps. Once equipped with DPL IIx , it will be thoroughly up to date and hard to beat for features, usability, price, and performance.