Conrad-Johnson PV10 preamplifier
By Corey Greenberg & Sam Tellig   •   June, 1993 Last September, in Vol.15 No.9, I started my quest for the Ultimate Kilobuck Tube Amp with reviews of the $995 Panor/Dynaco ST70-II and the $1695 Nobis Cantabile. While neither really fit the bill—the Dynaco fell a bit short in terms of sonics, while the Nobis was priced a bit higher than a thou—they got me thinking of the Ultimate Kilobuck Tube Preamp. Because the greatest amp in the world can only sound as good as whatever drives it, and there's no sense looking for a kick-ass affordable tube amp if you're going to play Scrooge McDuck when it comes to the preamplifier.

Now, the Conventional Audiophile Wisdom when it comes to slinging together a Real World rig is to blow most of your carefully budgeted wad on speakers and amplifiers, leaving just enough for an inexpensive preamplifier to link the whole thing together. After all, how much does the preamp matter if you're not really putting together a state-o'-the-art system?

I'm here to tell you that it matters just as much to have a good solid preamp in a Real World system as it does in a Fantasy Island rig—maybe more so. If you've got big bux to blow, there are plenty of cool-man Class A and B preamps to choose from, each and every one capable of passing along true high-end sound to your amp and speakers. But as you start coming down in price, it becomes harder and harder to find a good preamp that won't strangle your system's sound.

For starters, forget the el-cheapo Budget King preamps from the offshore names that bring you the great inexpensive CD players and amps. I've listened to a number of them recently, and, even with suitably lowered expectations, I was not impressed. There isn't a $500 full-featured preamp in the world that's going to give you true high-end sound; Steve McCormack could barely bring his Standard Line Drive in for $650, and that was just a passive line-stage! No, if you're putting together a Real World system with a turntable and want better sound than a receiver, you might not be able to afford a Class A preamp, but you can't afford to skimp, either.

So when C-J's Tor Sivertsen came to town to deal with a dealer, I took him to Sam's BBQ and he told me all about their $995 all-tube PV10A preamp. Whether it was the pork ribs or the tube-talk, my mouth was watering, and Tor promised to ship me a '10A as soon as he got back to Virginia. A sub-thou all-tube Conrad-Johnson preamp with circuitry derived from the company's most expensive models sounded like just the thing for Real World music lovers who still cling to their turntables.

But I have to let you in on a little secret: It was the pork ribs.

C-J PV10A: $995
On the face of the PV10A are three golden knobs for source selection, balance, and volume control. The balance control can be bypassed out of the circuit with a small pushbutton switch located next to it. There's another pushbutton for monitoring the tape loop, but no, it's not that woo-scary-woo C-J trademark kind that will send speaker-destroying feedback to your amp if you push it while your tape deck is recording and you happen to mosey the selector switch over to listen to the Aux inputs you hooked your deck's outputs to.

Look. A lot of ink has been spilled in these and other pages about how EVIL, Ah say, Ah say EEEEE-VULL this tape-monitoring arrangement of C-J's is—how you could easily fry your speakers, how the tweeter-searing feedback caused by the Doomsday Scenario described above will temporarily scramble your DNA code so you go on a rampage, terrorizing innocent school kids and eating all that gross baking chocolate in your wife's cupboard.

C'MON! Why would anyone punch the tape monitor button and then twiddle the selector switch to the tape deck, too?! Even I'm not that dumb, and I like the McRib samwich.

The littlest C-J may be the cheapest full-featured tube preamp on the market, but it sure ain't the ugliest! In fact, the suave-looking PV10A looks like higher-priced C-J jobs, such as the Class B-ranked $1895 PV11 and $8950 Premier 7A (footnote 1). The brushed-gold front panel and knobs give the PV10A a much more polished look than any other sub-thou preamp I've seen; there'll be no need for apologies when hosting your local audio-nut meeting.

It's when you reach the backside of the preamp, though, that it becomes obvious where C-J had to cut some corners to bring this baby to market under a grand. The typical "Tiffany"-style precision gold RCAs are nowhere in sight; instead, C-J fits the PV10A with much less expensive RCA jacks that, gold-plated though they are, are a bit closer to the typical el-cheapo Radio Shack and Mouser types than the chichi Tiffanys. Five pairs of these RCA jacks are provided for Phono, Tuner, CD, Video, and Aux inputs, while four more pairs source the Tape Ins 'n' Outs and two paralleled Main Outs. The nondetachable 18ga two-conductor AC line cord sports a non-polarized plug; that is, both prongs are the same width instead of one being wider, so's you can only plug it in one way. This allows the user to make sure the PV10A is plugged into the wall with the proper AC polarity (footnote 2).

---

Footnote 1: Reviewed by RD and JE in Vol.14 No.2 and Vol.15 No.5, respectively.—Corey Greenberg

Footnote 2: To measure this for the PV10A—or for any other gear—plug the unit into the wall and make sure it doesn't have any interconnects or other signal cables connected to it. Now take an AC voltmeter and measure the AC voltage between your house's AC ground (the "third" or round hole on an AC outlet) and the ground of your component (any outer ground surface of an RCA jack), first with the unit plugged into the wall with one plug orientation, then with the other. Whichever orientation measures the lowest AC voltage is the correct one. Puh-leeez don't go sticking your voltmeter probes (or any other probes of any type of your own, for that matter) in either of the two thin slots in an AC outlet; you can easily shock the bejesus out of yourself when diddlin' with a live AC outlet—and we don't like to lose readers unnecessarily. (Michael Bolton: If you're reading this, please stick your probes in the two thin AC slots.)—Corey Greenberg