But first, some explanations from Chris Hoff, as to what really makes the BP-3.5 Sig leap-frog over the previously reviewed BP-2+: "The performance of the NBT/LoNo transformer without all the extras added to this unit (cryo treatment, Z-Sleeve, triple damping, ERS cloth, Gold Fim AC plug, isolation cones etc.) is better than the LoNo - but not by a wide margin. It's all the extras that make the difference. I have spent a lot of time tweaking these units to reduce RFI/EMI and you are hearing the results. It takes a lot of effort to drop the noise floor down to this level. It is similar to Krell and Levinson trying to beat the performance of their previous models. Once you get to a certain point, it takes a lot more work and money to squeeze out better performance. I will be offering this extra tweak package as a Signature Model upgrade also for my other units, and with similar results.


On a personal note - about 5-6 years ago, I got the battery bug and designed my entire reference audio system to run off sealed lead-acid batteries. The sound was glorious. So much noise was removed that I found it quite uncomfortable to listen to other audiophiles' systems for more than a few minutes. When I first decided to build power conditioners, my reference system proved to be the perfect test bed - because I can run it off DC or AC at the flip of a few switches. The better my AC conditioners worked, the closer the system sounded to full battery operation. Until now and for enjoyment, I would only listen to my system with DC power - the AC just didn't cut it. With the BP-3.5 in place, I can now listen to my system for hours in AC mode with relaxed appreciation. It's still not the equivalent of pure DC operation. But, it's damn close. And I do have a couple of more ideas I'm working on."


As will be obvious to devotees of big amplifiers? Big transformers tend to hum - big-time. It goes with the territory. The BP-3.5 Sig's brutally oversized LoNo/NBT transformer was cut from much finer cloth. Chinese silk, for dead-quiet. So was the previously tested BP-2+. From past experience working at Mesa/Boogie, I'm hip to small possible tolerance deviations, from one batch of transformers to another. It's theoretically possible that one of these units could exhibit very minor hum - but thus far, my two review loaners from BPT suggested that both Plitron and BPT go through significant pains insuring that they're not humming. This is a far more significant compliment than you may realize. Consider that $10,000 tube amplifiers with transformers half the size of the BPT's commonly exhibit hum levels noticeable from 1-2 feet away. The BPT remained inaudible squatting right next to it. This told me two things. First, Plitron's LoNo designation isn't marketing hype but honest specmanship. Second, to make and purchase ultra-quiet 2400VA transformers costs significant money. With certain product, you may be excused for wondering where your discretionary audio funds have really been spent - glossy $5,000/page advertising, most likely. There's no such suspicion with the BP-3.5. Time to heave its mass and pop the DeadBall isolators underneath which, thankfully, sported a higher profile than the stock footers to not require prior removal of the cones.




The DeadBalls introduced some additional - ahem, roundness particularly in the vocal range, clearly discernable in Linn's fabulous new Barb Jungr release Waterloo Sunset [222], say on "The Great Valerio". While creating an even more organic feel for Barb's voice, the balls also slightly softened image outlines, particularly with the background instrumentals, and in the percussive transients.




The Stillpoints with risers refocused this minor softening, adding a few degrees of 'presence lock' on Barb's lead, also benefitting the accompanists with enhanced definition. Going back to les points, I found the black pyramids with ball bearings to sound more refined, albeit not at the expense of articulation as produced by the dead beats - DeadBalls. For my ears, the "stilled" BP-3.5 was the ticket.




This told me a third thing. All truly dialed-to-the-max components become more rather than less sensitive to even apparently insignificant tweaks. Think of it as the difference between an electron microscope set to resolve a single molecular layer of tissue sample, versus an amateur's 'scope enlarging the mere surface of said sample. The former will go out of focus when exposed to even the tiniest of external vibrations. The latter's too coarse to even register this disturbance and parlay it into visible distortion. Ditto for expertly calibrated, hi-rez components. The readily noted though not drastic audibility of footer substitutions on the already well-damped BP-3.5 -- sitting itself on a spiked solid-wood platform, if you can believe that -- demonstrated this truism to perfection. Rather than reacting aghast [damn, isn't this bloody thing awfully finicky?], you have to give it credit for being sensitive enough to resolve what on the surface seems impossible, ridiculous and the stuff of vivid imagination or anal-to-the-extreme audiophilia. Not! It's simply a truly upscale component that rewards attention to details with user tuna-bility - not a smelly but hands-on get-involved proposition just as it should be.


Replacing the $2,495 balanced power unit with the $3,800 Audio Magic Eclipse showed the latter to be possessed of less mass, weight and density, casting a nearly artificially deep soundstage with equivalent lateral expanse but lacking the BPT's sheer balls-to-the-wall impact. The Eclipse was ultra-refined, going after a bit more ethereal and silvery sound, apparently more transparent but not actually so, just possessed of less red meat on them bones. The previous energetic mien of the Stealth family of conditioners has been tamed a bit, now sounding less geared for speed and transients, more tweaked for extreme dimensionality. The Eclipse is for space travellers - audiophiles who value cavernous soundscapes, with that high-contrast sense of object against silence.


The Eclipse drew my attention to the blackness between the notes. With the BP-3.5, I was never aware of the silence per se, always only attuned to the music. Think of this as the difference between positive and negative space. Look at a tree and concentrate on the trunk, branches and leaves. Then shift perspective and see the emptiness between the branches and around the leaves. It's still the same tree but it looks - different. The Eclipse emphasized the latter perspective, for $1,300 more. Compared to the Velocitor, it was far more similar than either were to the BPT, something we'll cover in greater detail in the upcoming Eclipse review.




This now returns us full circle to the BP-3.5 Signature's core - ahem, signature: Image density. That's different from harmonic density. The latter is a function of THD distribution, most commonly achieved with tubes somewhere in the chain. The former? I'm not sure what causes it but the Audio Oasis Amp-1 had it in spades. As does this piece. Trust me - though I can't explain how it works, when it's present, it stares you down like a yellow-eyed big cat. There's no argument whether you're about to be pounced on: You're toast for a tiger. Call it the old "so thick you could cut the air with a knife" thing. It bears repeating that the BP-3.5 Signature pulled this density stunt at the same time that it upped the ante in the resolution department, of tertiary events buried underneath more obvious musical material. It did offer distinct full-bandwidth warmth. But fuzziness? Bupkes. That was a rather unexpected and usually mutually exclusive trick. It's why I'm purchasing this very unit. It's why it gets our Blue Moon Award. Incidentally, there's one more item I haven't yet mentioned - because it became available only at the very end of this writing gig, something I'd been told to expect but completely forgotten. How so? It didn't seem to be missing: A nicely sculpted bolt-on face plate that's, gasp, included in the price. So was the $399, 20-amp Litz power cord with mono-crystal copper, hi-current Fim plug mentioned earlier [above]. All the component pix thus far were of the 'nude' BP-3.5 which, to this free-love commune-reared boy, never once telegraphed nude. However, a laser-engraved, 1/4" thick, cross-grained and clear-anodized dress plate by overnight FedEx showed me the error of my ways.




Doesn't it seem as though Chris Hoff was excessively zealous about providing superior value? Perhaps he's making up for having sold crappy audio to poor suckers in his last life? If so, he's bound for St. Pete's gate this time around. The conditioner saint.


Envision him floating on his phat cloud, listening to loud and complex Funk while everyone else suffers lean and thin harp arpeggios on endless repeat. Guess what cloud I'm gonna visit - if I don't end up in hell for seducing starving audiophiles into spending their grocery budgets on High-End toys? Hey, it's not as though anyone ever got hurt by superior sound, is it? There's my answer for St. Pete then - innocent!

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