Dick Olsher is currently Senior Contributing Editor at Fi Magazine and was formerly Senior Contributing Editor at Stereophile Magazine.
"Undiscovered High-End Esoterica"
Dick Olsher's Audio Mecca
A Tale of Two Line Stages I have a confession to make: I have strayed off the beaten track. For years I've been puzzled by the paucity of truly great sounding preamps. The situation is really paradoxical in that I have no trouble at all in locating great sounding amps or speakers -- products which to my mind are technically more challenging. Yet, something as simple as a line stage seems to frustrate me. Oh where are all the great line stages hiding? Reduced to its basics, all you really need is a single voltage gain stage per channel, a stereo volume pot, and some switching capability (i.e., a function selector). It almost sounds trivial, but over the years, my search for line stage excellence in the highways of mainstream audio has pretty much come up empty handed. And so, I've started to search the byways and investigate several offerings from small audiophile-grade companys. The road less traveled has been rewarding as you can tell from the following capsule reviews of two of my favorite line stages todate: the Presence Audio (First Sound Co.) Line Stage I ($3,200 in deluxe version; $2,800 in basic version without fancy face plate), and the Canadian Blue Circle Audio BC-3 ($3,300). You will, I'm sure, notice some remarkable parallels between these two units in terms of circuit architecture and design philosophy. Could it be that these units are singing Tube God's true gospel? ...... Gilbert Yeung, Blue Circle Audio's progenitor, recalls his childhood when his parents bought their first stereo system. It was a Sansui combo complete with a receiver, cassette deck, and a turntable. This was his first exposure to anything more sophisticated than a 1970s version of the "ghetto blaster." Young Gilbert began to appreciate the difference hardware makes in the enjoyment of reproduced music. By age 13, he was already studying various audio systems and planning his ideal setup. His amplifier design philosophy can be best summed up as wire with gain. A minimalist approach, founded in the belief that circuit simplicity and signal purity go hand in hand. A single Sovtek 6922 dual-triode is used per channel. One of the triode sections is used as a conventional voltage gain stage (24.7 dB), while the other is deployed as a buffer stage. No global feeback is used. The buffer stage confers low output impedance (27.5 ohms), a critical parameter in driving long cable runs. Since Mr. Yeung's ideal system configuration consists of long interconnects and short speaker cable, the BC-3 not surprisingly is designed to drive up to 150-foot long interconnect runs with adequate gain for even insensitive power amps. Visually, the unit is a certified beauty-contest winner: a stainless steel, non-magnetic chassis, adorned with hand polished hardwood knobs, and that really cool bluish glow of the Blue Circle logo. A startling contrast of old and new. Black cherry is standard, but a variety of optional woods is available. In this case, beauty is much more than skin deep. Be sure to take the cover off and feast your eyes at the BC-3's internal organs. The layout is dual-mono with separate function selector switches and attenuators for each channel. The Shallco military-grade ladder-type stepped volume attenuators are absolutely spectacular. Note also the absence of a conventional circuit board. The active circuitry is mounted on a quarter-inch thick acrylic board which floats on spring-loaded stand offs for isolation and vibration control. All wiring on the board is point-to-point. An outboard power supply is used to locate the power transformer away from the main chassis. Both of the main outputs invert polarity. If you're shopping around for a romantic, euphonic sounding preamp, in the classic tube tradition, then this unit is definitely NOT for you. The sound, with one exception, was uniformly true to the original tonal balance and harmonic colors. No editorializing, please, is the BC-3's middle name. Harmonic textures were smooth and pristine without the tube glare and brightness endemic to so many tube preamps. Midrange textures were lucid and vitalized with a natural sweetness. I found the integrity and cohesiveness of the soundstage to be quite endearing. Spatial detail was painted with a fine brush that readily resolved massed voices and the air around individual instruments. There was plenty of low-level detail to behold. Detail lofted naturally from a low-noise floor, in the same manner that a soap bubble dances through the air. Some preamps specialize in force feeding the listener an earful of detail; more accurately, a barrage of in-your-face zingers that becomes almost an instant irritant. The BC-3, on the other hand, allowed me to enjoy an ensemble sound as an organic whole. I could tune in the orchestra without being distracted by discrete detail. Yet, I could also -- at my leisure -- re-focus my attention span onto particular nunaces and retrieve them at will. The impression of speed and control was strong. Transients were unfolded with first-class attack and controlled decay. Multi-track recordings were readily exposed in terms of EQ and reverb settings for individual instruments in the mix. Few preamps possess a full palette of harmonic colors through the upper mids and presence region. Too often colors are bleached out so that the vividness of soprano voice withers. This being a priority of mine, I attach considerable weight to a preamp's performance in this area. Color shadings were superbly reproduced by the BC-3 throught he upper registers. This part of the spectrum was also wonderfully transparent. The BC-3 edges out the Presence Audio line stage in this respect, but does not equal the latter unit's suaver and more robust lower midrange. The BC-3's lightly lean lower mids will require careful matching of components downstream to maintain timbre realism. Certainly, this would be the wrong preamp for overdamped loudspeakers. Overall, I would rank the BC-3 as a world-class unit and a strong 9 out of a perfect 10. In view of the price to performance ratio, I'd say buy now before Blue Circle catches up with standard high-end marketing practices. Blue Circle Audio may be contacted at (519) 469-3215. Audiophiles may also contact Madcap Audio at (416) 487-3594, and ask for Jonathan.