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Teleported into a sterile clean room. Upon insertion of the copper-wired PRE-T1 to replace my customary ModWright SWL 9.0SE into the Audio Sector Patek SEs, that's how I felt. The Germans have the perfect word for the sound I'm -- unexpectedly but very happily -- getting from the combination of 5687 valves in Dan Wright's hybrid preamp and the National op-amps: schwühl. It roughly translates as sweltering. Think elevated air pressure, moisture and temperature to feel like a tropical post-shower session. Colors are vivid and your skin feels moisturized and glows from the inside. In the Patek's review, I've called that oppressive. It meant to parlay a very tacit and thrilling sensation of intensity. The PRE-T1 completely annihilated it.

Of course, tube man was now down to one lone 7308 in his Zanden Audio 5000 Signature DAC (its 3K Z-out definitely copasetic with these transformers). Perhaps I shouldn't have been surprised. The results reminded me of the findings I share with others who've at length investigated active power line conditioners. After a while, we've come to confess that subtracting the nth degree of micro noise becomes unnatural. It's as unnatural as an outer space vacuum is to oxygen-sucking beings. You can't breathe. Together with the subliminal noise, most active AC line filters kill off something else (dynamics for one) that listeners like myself insist must stay alive. Within seconds, the PRE-T1 very obviously removed something. The instinctive reaction was to call it noise. There definitely was less noise. But if what emerged instead was perfect silence, it didn't feel like the throbbing silence of an old forest. It felt like an air-brushed, heavily made-up centerfold whose every hair remains in place despite a breeze. Frozen.

At 8.5" x 6.5", the Pretty One is a small but heavy bugger. Physically heavy, that is. 9.5 lbs to be precise. But sonically and into this solid-state amp, it's too light for my taste; ultra-transparent and truly silent as a grave but too passive to stir my thermionic heart.

Being a passive device, that's of course exactly as it should be. Add nothing, remove all filters. Alas, the ModWright didn't suggest filters. It sounded like expanded density, moisture and fullness. Most importantly, it caused the sound to project and seduce. With the PRE-T1, it just sat there, squeaky-clean but lean and bereft of energy and cojones.

The solution was obvious - replace my Pateks with the Canary Audio CA-308 8wpc 300B monos currently in for review. Just as a system can err too far on the rez-über-alles axis, it can also overdo the sweltering thing to become slow, fuzzy, indistinct and stifling (incidentally not at all the case with the ModWright/ AudioSector combo). When I first received the Canaries, they definitely fell into the weighted-down-by-excess-girth camp. To break in, they'd moved into the video system where the Bel Canto PRe2 -- text-book active but sonically passive -- gave a much better showing of them right off the bat. It made sense to predict an equally copasetic pairing for the Canadian passive.

The wicked never rest. At right, Peter Daniel's current just-for-the-hell-of-it prototype integrated. It combines a TVC front end with balanced Pateks at the output, in a configuration where the preamp section won't operate entirely passively. After my somewhat disappointing first foray into the PRE-T1, I fired off an e-mail to its designer. Was his new Patek SE less than ideally mated to the PRE-T1? As it turns out, George Tordai, owner of the Audio Zone brand, prefers BlackGate STD caps over the N versions that the Patek employs as bypass caps.

Consequently, the Audio Zone AMP-2 monos don't run N caps. That's said to make the perfect match for the PRE-T1. The next AudioSector project meanwhile is rumored to be an active solid-state preamp. So I wasn't deaf or in a bad mood. Moral of this story? Passives are very application-specific.

The S&B transformers will be mounted laterally into wells inside the two wooden rails in the empty space upfront
In that spirit, color me yellow now! For me, it was Canary time. Outfitted with KR Audio's rockin' new Western Electric 300B clones, the Californian monos replaced the Patek SEs. Though a mere 8 watts, these monos are high-gain devices. Even after their input sensitivity mod (performed at the factory to become better matched to my 101dB Definitions), they still elicited a modicum of noise run off the ModWright preamp - nothing gnarly at all, just not dead silence. The no-peep quietude of the PRE-T1 would probably turn out to be a secondary boon in this scenario.

Affirmative on both counts. What I had now was in essence a tube amp with an attenuator. I used to own one in Art Audio's PX-25 with the optional GoldPoint stepped attenuator. At that time and after some experimentation, I  concluded that in order to do better than that quasi integrated setup, a stand-alone preamp would have to cost upward of $3,000.

Going all tube is sometimes inadvisable and overdoing things. That's especially likely when you already own a truly excellent valve amp whose voicing, THD distribution and loudspeaker interaction don't warrant any additional seasoning. You still gotta control volume and, ideally, switch inputs as well. This is where the AudioZone PRE-T1 now hit its stride. Since I didn't require gain but mere attenuation, the preamp's absentee noise floor with its concomitant heightening of micro detail and -- subjectively speaking -- apparently improved rise times or spicier jump factor were ideal bed fellas for the Canary monos' apparently more languid and dense nature. It also made the amps dead quiet. Yousa.

The core consideration here really hinges on whether your system requires an active or passive preamp. How to know whether a passive is enough? That's simple - if your sources can drive your amps direct and louder than you'd ever listen to. But that still doesn't mean you wouldn't prefer an active. You won't prefer it for the redundant gain it provides (you don't need any of it and will never listen to it since the preamp will operate below unity gain). You might prefer it for the expander action a good active can provide in the spatial, tonal and dynamic domains. There's no way to know except try.

Passive pre + tube amp vs. active pre + solid-state amp? At least conceptually, that had a certain symmetry. In my scenario, the question became whether actual listening would bear out that active pre + tube amp equated to less satisfactory results than passive pre + tube amp. If equally satisfactory simply for different
reasons, what would those differences be? [For the DIYers amongst you, I've included a picture of Intact Audio's $200/ea. autoformer volume control that'll serve home-brew experiments for this particular "variac" scheme of controlling volume without traditional potentiometers.] Incidentally, some people believe that transformers compress dynamics. If there's no DC bias and they aren't driven to saturation, that theoretically shouldn't be possible (however, it's said that the opposite is possible at low levels due to core material behavior). Finally -- while we're still theorizing -- it's getting tiresome to be accused of liking coloration whenever the subject of tubes comes up. How about color? Music's full of colors. If one expects to see and hear the full magnitude and saturation of those colors during playback, does that mean one prefers colorations to so-called signal truth?

The copper PRE-T1 into the Canaries was the hammer. Tube drag be gone. Tube fuzziness be gone. The passive acted like an Aspirin blood thinner (clearly as it did into the Pateks earlier where it wasn't welcome). No longer burdened by "already enhanced" signal to get a bit bloated in turn, the 300B monos now proved that all the ills people hold against those tubes needn't be gospel - if the amps are superior, the tubes of linear quality and both allowed to run free. Forget ponderous, midrange-heavy, nonlinear and soft.

Except for a controlled amount of tone -- color, dammit -- and the valve-typical soundstage layering, the performance now had precious few obvious tube qualities. Along the transient/bloom/decay axis, things were very balanced in fact. The needle had moved left, away from the bloom/decay area that can become too echo-y and blurry. It now sat pretty much smack center. Transient speed was excellent but balanced against fullness of timbre and appropriately long fades.

Reinserting the ModWright incurred a minor damping of energy, took a step back resolution wise, increased system noisefloor and moved the needle toward the right a bit. While that change of gestalt will be a matter of taste, one aspect of the performance that was unquestionably better? Microdynamic scale. The tube pre had more. Purely based on previous preamp comparisons, I'm inclined to believe that the PRE-T1 wasn't subtractive. Rather, the ModWright seems to be additive in that department. That would seem logical. It is active after all. Presumptious? Perhaps.

On balance, however, I preferred the PRE-T1 on these amps and not by a small margin. What I gained -- or better, what was subtracted -- far outweighed the one thing that wasn't added. I also had no complaints about the volume steps which, at least theoretically, might have some folks opine that if TVCs are supposed to control volume, they do a shitty job of it by restricting the end user to a few predetermined values. In my context and especially on the tube amps with their lower amplification factor than my chip amps, such complaints proved entirely conceptual. In use, I was never short the level I wanted - or else, I wasn't picky enough to realize that I really wanted a half a dB less or more. Either way, another non-issue in my book.

Now here's a thought. How come nobody has authored an active TVC yet? The PRE-T1 offers a +6dB setting but think vinyl step-up trannies for real gain. Couldn't a transformer be wired such as to provide active gain in 1 or 2dB steps above unity to offer passive/active performance and, say 20dB of gain with zero noise and no batteries? Fade out dream, zoom back into reality. Don't take the above comments to mean that the PRE-T1 would be automatically superior on every tube amp. For example, the Decware Zen Taboo responds very favorably to active action on the preamp front to build out harmonic envelope and tonal density. That said, I do think that, generally speaking, a passive pre could be the ultimate solution for tube amplifiers that don't need any assistance except not to be weighed down by a preamp. Put differently, if most tube amps don't hold their alcohol very well -- they're already slightly tipsy to begin with -- serve them table water, not more alcohol.

Here's an interesting tidbit: ModWright/Patek vs. PRE-T1/Canary. These two systems were now far more similar than not. The former was a bit more incisive, dynamic and (surprisingly) with denser images. The latter was tonally slightly fuller and somewhat more relaxed. In truth, this difference belonged mostly into the gestalt domain rather than any clear-cut more-of-this, less-of-this measurables.I could live with either and consider myself married to an identical twin - nearly indistinguishable to strangers but still with personality differences you'd appreciate once you'd live with whatever twin ended up wearing your ring.

Next up? PRE-T1 into NuForce Reference 9s and 47Labs Gaincard, then copper vs silver into today's amplifiers and those other two. As well, a bypass test, running the Consonance CDP 5.0 Droplet (with its fully balanced tube output stage and variable outputs) direct into the Pateks, then inserting the PRE-T1 to determine whether it "subtracts" dynamics by comparison. For now, my preliminary conclusion is as follows: The PRE-T1 allows you to hear your amps like you perhaps have never heard 'em before. That's because the preamp stage's usual contribution -- to dilute or enhance the mix -- has been taken out of the picture. Gone. One less singer in the chorus and the voice of the amp becomes that much louder, for better or worse. That's really the decisive factor. If your amp acts perfectly in the context of your system, go passive to hear the amp, nothing else. If your amp misbehaves or underacts here or there, go active and pick a preamp that merely fills the holes the amp leaves in the picture. I know, that math often doesn't work out so cleanly. Still, talking about it in those terms seems the best way to explain the basic concept of passive preamps. With a tube amp as well-balanced as the CA-308s and then outfitted with the ultra linear KR Audio 300B WE clones, passive is where it can be at!