Boulder 850 Monoblock Amplifier

Perfecting the technique of “deep focus”

While filming Citizen Kane in 1941, legendary c i n ema t o g r a p h e r Gregg Toland first perfected the technique called “deep focus.” His goal was to shoot the film in such a way that the audience would feel like it was looking at reality rather than a movie. Shooting with a much smaller aperture setting than had previously been used and hundreds of times more illumination, he was  able to photograph the set in such a way that the camera captured space the way the human eye does, i.e., with all of the objects in the scene, whether in the foreground or in the background, simultaneously in focus, thus the term “deep focus.” Toland’s work revolutionized cinematography forever.

Boulder Amplifiers, while not revolutionizing audio forever, has nonetheless achieved an equally dramatic “deep focus” effect with its new entry-level (for Boulder) 850 monoblock amps. The $10,000/pair 850s recreate the musical reality of a performance by bringing all the performers, whether in the foreground or at the back recesses of soundstage, into sharp focus. Where Toland achieved his effects by using lens settings and illumination, the Boulder 850 amps achieve theirs through remarkable details, dynamics, and resolution.

Unlike a movie where the camera records the image of a set filled with props and people, an audio system has to create an image in the listener’s mind of an unseen performance space. And this the Boulder does in spades. The 850s consistently created a soundstage that wrapped around my ears and dissolved the walls of my listening room. As I noted at one point in my audition, “the soundstage ate my speakers and then it ate my room.” Not only was the soundstage wide and tall, it was, depending on the piece, deeper than I have ever before heard in my listening room.

But this cavernous, black soundstage was only one aspect of the overriding characteristic of the 850s: its ability to present more musical information more realistically than my reference system ever did before. With the 850s, the way Jennifer Warnes used her breath to create Max Shepherd phrasing on Famous Blue Raincoat [Ariola- Eurodisc] was more apparent, better conveying the emotional content of the song. The 850s also consistently revealed more of the timbre of instruments. For example, the shimmer of the cymbal in Keith Jarrett’s Out of Towners [ECM] radiated out like the rings of Saturn. The clarinet in Yo Yo Ma’s Obrigado Brazil [Sony] had more apparent woodiness and, thus, threedimensionality. The soundboards of pianos sang, stretching out the decay of the notes and chords that hung in the air until they became mere whispers. And more importantly, pianos sounded like pianos, which I find to be a good test of any system.

The 850s also excelled at placing performers correctly within its large, black soundstage, highlighting their performances by surrounding each player with a greater sense of air. For example, the 850s clearly separated the members of the Keith Jarrett Trio and Eva Cassidy’s Band in Live at Blues Alley [Blix], locating each performer in three-dimensional space andeliminating any sense of congestion in the middle of the soundstage.

In this same way, the 850s teased out each line of a musical performance—an attribute most noticeable on large orchestral pieces. For example, on track six of Obrigado Brazil there is a passage where a violin is playing ever so faintly near the top of its range while the cello and other instruments are playing much more robustly in the foreground. The 850s never lost track of that violin’s voice or of the musical phrase it was playing. This resolution was also apparent with Pierre Fournier’s reading of the Dvorák Cello Concerto [DG], where the oboe is playing quietly toward the back of the orchestra. With the 850s, the oboe’s voice was never lost nor its tonality diminished. It was presented with the same clarity and accuracy as the louder  instruments in the foreground. In fact with the 850s it was possible to shift one’s attention to any instrument playing in the orchestra or group, to mentally wander around the soundstage so to speak, and stop and enjoy a given instrument wherever it was located in the soundstage. It was this aspect of the 850s’ performance that created the sense of “deep focus.”

Indeed the 850s’ resolution was really its outstanding attribute, because when an amp is able to preserve low-level detail, all aspects of the performance are enhanced. The soundstage is more three-dimensional, instruments are more realistic in timbre, lyrics are better articulated, vocals are more life-like, and the music is ultimately much more engaging. While it is a small thing, being able to hear Jacqueline du Pré’s fingers rocking on the strings of her cello while her bow pushed against the strings’ resistance greatly increased my enjoyment of and engagement with her version of Dvorák’s Cello Concerto on EMI.