Conrad-Johnson ACT2 line preamplifier Wes Phillips, November 2007

Wes Phillips wrote about the ACT2 Series 2 in November 2007, Vol.30 No.11:

When I reviewed Conrad-Johnson's $7500 CT5 preamplifier in the July 2006 Stereophile, after having reviewed their $13,500 ACT2 in March 2005, I was struck by how very close to C-J's flagship the less expensive line stage sounded. In fact, they were so close to sonically indistinguishable that I found it difficult to imagine why an audiophile might choose the more expensive option.

"Actually, we wondered that, too," said Lew Johnson when the review was published. "So we took what we learned building the CT5 and applied it to the ACT2. Frankly, we were stunned by the ACT2 Series 2."

The CT5 replaced the cascaded power-supply regulators of the ACT2 with a single stage of regulation with twice the storage capacitance. "Well, it was the same amount of capacitance and filtration as both stages together," said Johnson. "This better rejected the noise on the AC line. The audio circuits are drawing on a single, larger reservoir, which, we think, makes the power supply more stable—less responsive to the demands of the circuit. Splitting the power supply didn't reduce AC noise, but it did reduce the capacity of the reservoir."

C-J incorporated the single-stage regulation into the ACT2 Series 2 and also replaced polystyrene capacitors in a few crucial areas—the tube bias circuits and the AC input bypass—with Teflon capacitors. "They are hideously expensive," Johnson said, "but quality polystyrene caps are simply unavailable these days. The only choices left are lower-quality polystyrene, polypropylene, and Teflon. Since we're about sound quality, we decided that if that meant we had to sell products that cost more in order to sound better, we would have to do that. We just weren't willing to downgrade the products to keep the prices in 'line' with an arbitrary price point."

The ACT2 Series 2 also includes an internal mechanical shield to further reduce the residual noise, making it significantly quieter, according to Johnson.

The ACT2 Series 2 lists for $16,500, which, Johnson says, reflects the costlier parts and "the passing of a few years since the introduction of the ACT2." Original ACT2s can be upgraded to Series 2 status, but "that's an expensive process because we have to essentially take the preamp apart and build a new one. Labor costs and parts costs conspire to make this costly: It's $5500, and a bargain at that."

ACT2 Scene 2

When I reviewed the ACT2 in March 2005, I carped about how long it took the preamplifier's Teflon caps to "play in." The preamp's sound was hard and uninvolving for a few hundred hours, but then blossomed remarkably. But despite having even more (and higher-capacity) Teflon caps, the Series 2 spent less than half the time playing in.

When I asked Lew Johnson if he'd played-in the Series 2 at the factory, he chuckled. "Actually, we spent a lot of time playing your original ACT2 before shipping it to you. This one we just shipped off the line."

So why did the Series 2 hit its peak faster?

"Truthfully, I don't understand why capacitor wear-in works at all, and it would sure make life easier if things we can't explain didn't happen."

Couldn't have put it better myself.

Listening

I had to return the ACT2 to get a Series 2, so I couldn't directly compare the new, improved version with the original. However, I employed every foot-dragging, passive-aggressive trick in the book to keep the original ACT2 in my system for an obscenely long time, connecting it to the widest range of gear I could parade through my listening room, so that it would be safe to call the original "my reference" preamp—even if the "my" is stretching things a tad.

In other words, I know what the ACT2 sounds like. The ACT2 Series 2 sounded exactly like the original—more or less. More dynamic and detailed, but less of anything that didn't sound like live music.

What am I talking about? I've already said that the original ACT2 and CT5 were revelatory in their transparency. How much better could the ACT2 Series 2 be? Enough to matter, apparently.

David Russell's Renaissance Favorites for Guitar (CD, Telarc CD-80659) had discernibly more snap and decay than I'd heard before. Russell's guitar seemed more solidly between my speakers, and the recording's acoustic was more detailed—down to the physical boundaries of the venue, not simply its space.

I'm not saying those were my immediate conclusions—that's more analytical than how I operate. What I did was eventually notice how much I was grinning every time I listened to music, even recordings I'd heard dozens, if not hundreds of times. Then I asked myself why.

Why? I was hearing more.

And less, of course. Listening to Leonard Bernstein's in-concert recording of Mahler's Symphony 2 with the New York Philharmonic (CD, Deutsche Grammophon 433 395-2)—a warhorse I drag out frequently, not simply because it's a performance for the ages, but also because I was there and it was the last time I experienced the music making of one of my heroes—I was pinned to my listening chair by the NYP's dynamic shifts.

As I say, I've listened to this disc a lot—and I've always suspected that Lenny gleefully decided that, if audiences found that his later Mahler performances too rapturously mined the dynamic extremes, then he was going to really give them something to talk about during that week's run at Avery Fisher Hall. Even so, the ACT2 Series 2 made that performance a whole new ballgame. Spend much time in Fisher and you'll hear its signature sound of acoustic overload whenever an orchestra (usually the NYP) decides to turn it up to 11—and that was one evening I definitely heard that effect in that hall. The ACT2 Series 2 put it in my listening room.

Oh boy, I hear you thinking, a $16,500 preamp lets me hear the sound of a hall complaining? Well, it's on the disc—don't you think you should hear it? The Series 2 also let me hear a lot of performers with whom I am very familiar sound as I had never heard them before—on recordings, at least.

So why do I say that, with the ACT2 Series 2, I was hearing less if I was really hearing more? The only way I can account for that is if the preamplifier actually was quieter, and allowed me to discern levels of detail that had previously been obscured, if even the slightest bit, by the ACT2.

Exeunt the Stage

If I sound thoroughly besotted by the Conrad-Johnson ACT2 Series 2, well, I am. Is it the best preamplifier I've ever heard? That's hard to say, primarily because both the Krell Evolution 202, which I reviewed in December 2006, and the Ayre K-1xe, ditto June 2007, rank among the most neutral, well-engineered preamps I have ever experienced. At that level, minor differences—perhaps even ergonomics—will determine which you want to live with.

All I know is that I simply do not tire of musical explorations with C-J's ACT2 Series 2. At $16,500, I cannot remotely afford it, but I lust after it, and would gladly forsake all others for it.—Wes Phillips

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