Blue Circle BC3 Galatea line-level preamplifier Page 2
"The 6922 has a higher current gain, and higher current capability, than the 12AX or AT, so it would drive a longer cable without any loss. So I chose that as the buffer stage. In the gain stage, because the 6922 is medium-mu and medium-gain, I can have a slightly lower gain on the preamp—which means you could have a higher signal/noise ratio and a blacker background on a long cable run. Just enough gain on the preamp to drive the power amp, but at the same time the 6922 is rugged enough to have a very high signal swing—it's capable of 25V RMS. And the output impedance of the Galatea is less than 180 ohms.
"Another point I would like to make is that since the circuit is so simple, and essentially adds no colorations of its own, you can tune the preamp to exactly how you want it by changing the tube. For production I chose Sovtek because it is a good, reliable tube and offers a nice balance of richness and precision.
"But if you wanted an even bigger, more accurate soundstage, you might try a Mullard, UK—if you can you find them. That's the problem. If you wanted to voice the Galatea to make it 'sharper' or more 'precise,' you could try something like Siemens Goldpins. Even lusher? A German-made Valvo, which is a 6E88CC, I think. I even have one customer who called me up and said he tried different brands of tubes: Brimar at the gain stage, Mullard at the output stage. Said it brought him to tears, because of the soundstaging."
An Army of Spinster Librarians
When I first paired the Galatea with my Mesa Baron and Celestion A3s, I was deeply moved. The word "creamy" came up countless times in my listening notes, yet with each CD and LP I auditioned, I observed that, "for all the lushness of presentation, there is nothing opaque about the midrange...the Galatea transforms my Baron into a Baroness." While subsequent upgrades to my original Baron smoothed out the presence quality of the midrange considerably, and allowed it to retain more air and transparency with added increments of pentode power, the 5881 tubes tend to have a brassy bite on top. The Galatea sweetened and softened things considerably—and was particularly forgiving of the Celestion's titanium-dome tweeter, enhancing resolution without any loss of detail.
Elsewhere in my early notes I find entries commenting on how the warmth of the Galatea allowed it to be "more forgiving of source materials where people err on the side of making things too hot and bright, with so much level it's almost unlistenable, and yet it doesn't attenuate the highs or blur the outlines of the music so much as soften the glare, while maintaining solid resolution. Curious..."
Curious indeed, but the Galatea's firm, laid-back musicality really blossomed when I substituted the Musical Fidelity Nu-Vista 300 Power Amp and a pair of Joseph RM7si minimonitors (on PolyCrystal speaker stands, sometimes augmented through the Galatea's second set of mains out by a Soliloquy S10 powered subwoofer) for the Mesa/Celestion combo. With this euphonically voiced, single-ended preamp now commanding 300Wpc into a nominal 8 ohm load, my listening notes began to take on a giddy character:
"Best of all worlds...sweet and silky, quick and slamming! Euphonic and involving, but with pinpoint resolution of images, as if an army of spinster librarians were bounding around the soundstage, organizing the images into discrete little sepia-toned events, carefully dusted, neatly alphabetized, and vividly back-lit for maximum focus and separation." Excelsior!
My final series of listening tests did nothing to dampen my initial enthusiasm. The Galatea proved equally compelling in its delineation of gestures large and small, and for its ability to track the fastest, most powerful transients while fleshing out delicate, ephemeral details with equal aplomb.
Nowhere was this better illustrated than by the playing of Pierre Boulez's definitive 1992 rendition of Stravinsky's The Firebird, Four Études, and Fireworks with the Chicago Symphony Orchestra (Deutsche Grammophon 437 850-2). The Galatea easily sorted out sounds of different speeds, durations, and textures while accurately tracking the leading edges of transients, such as the manner in which it delineated the instantaneous power of timpani strokes while maintaining the dynamic character and trailing overtones of more amorphous drum rolls—a clear point of demarcation, each surrounded by air in its own acoustic space, yet blended together as well, and correct both timbrally and in the domain of time and space. I was never left with the sensation of "waiting for the other shoe to drop," as kindly Rabbi Fremer puts it.
The recording quality and Boulez's ear for detail are to die for, and with its wealth of antiphonal details (say, where a phrase begins with a violin on the left and concludes with a violin on the right), individual voices popping out of sections all over the orchestra, and its slowly fattening dynamics, this Firebird truly illuminated the glory of the Galatea's rock-stable imaging and endlessly holographic soundstaging. The speakers seemed to disappear as sounds emanated from all around the point source: out front, behind, to the sides, and even out beyond the speaker field. And while the Galatea carefully tracked the orchestral swells, I could still reach out and touch a lonely triangle in the dense mists, even as I traced reverb trails far back into the inky ether.