Conrad-Johnson PV15 Preamplifier
by John Crossett
I love a good fight. You know the kind of bout Im referring to -- one where equally matched combatants go the distance, the outcome hinging on little things that may be unnoticed to the untrained eye. Think Hearns-Hagler or Ali-Frazier -- the stuff that gives the word "classic" its evocative power.
The audio world has these types of square-offs -- between competing products and even competing companies. Im in the midst of one right now between preamps from preeminent makers. It pits a challenger from Conrad-Johnson against my tried-and-true champion from Audio Research. The outcome? Read on.
The tale of the tape
The PV15 is the latest preamp in the longstanding Conrad-Johnson bread-and-butter PV (preamp/valved) series. It looks every inch a C-J product, with its classic champagne-gold faceplate. It clocks in at a regulation 19"W x 3 3/8"H x 13 3/4"D. Its also a solid piece, weighing in at a healthy 15 pounds.
Inside, the PV15 uses two types of 8080 miniature triode vacuum tubes. C-J chose these tubes for their durability, ease of accessibility, and sound. They claim that they know of no readily available replacements that sound as good. C-J feels that you should get a good two or three years of music out of the tubes before replacement with normal usage. They also recommend -- as do I -- not leaving the preamp on continuously, as this will shorten tube life. They recommend giving the PV15 at least 15 minutes of warm-up time before you do any listening in order to give the preamp tubes time to stabilize.
According to the owners manual, the PV15's line stage offers 28.5dB of gain, a maximum output of 5.5Vrms, and frequency response from 2Hz to more than 100Hz. About the only things missing from the PV15 versus it counterparts of yesteryear are knobs and switches. Theyve been replaced by round push buttons and a microprocessor. The buttons control input switching, the EPL passthrough, the home-theater-processor loop, balance, mute and volume.
All of these functions are available on either the front panel or the slim black plastic remote that looks wildly out of place with a preamp of this visual quality. Still, the remote functions just fine and probably helps keep the cost of the PV15 down to $3000 USD. One thing I find curiously missing from the remote, though, is a power button.You can switch power on and off from the remote, though, by pressing and holding the Mute button for off, and pressing the Mute button for on.
The preamp has a good-sized LED window that marks the volume level for each channel numerically. Each is adjustable in 0.5dB increments. If you use the balance control youll see the number of the channel you want to adjust go up or down depending on which channel you choose. I found that this system was preferable to the normally seen balance knob, where any adjustment is pure guesswork. The window also contains the C-J logo, which, as long as the unit it attached to power, remains lit. So I would guess that the power switch is in reality a standby switch and not a true power on/off.
The PV15 comes standard as a line-stage preamp with five sets of single-ended inputs, along with the EPL and Theater inputs. One of the main inputs will be used if you order the internal phono stage ($850), as the review unit was sent to me. You can request whether youd like the phono stage to be for use with either a moving-magnet/high-output moving-coil cartridge of 1mV or better or a low-output moving-coil. There is only one set of main output jacks. There is also the EPL output, which I used for connection to my headphone amp. One feature of the PV15 that had me almost doing cartwheels was that the preamp passes signal to the EPL output without having to be turned on. I think this is one brilliant idea, especially for a tube preamp. This way youre not logging hours on your precious (and expensive) tubes when you dont need to.
It's important to note that the PV15 inverts phase. Be sure to switch speaker connections to preserve system phase. Fortunately this is clearly spelled out in the very informative owners manual, which you should read before using the PV15, contrary to the usual audiophile wisdom of plugging in then playing.
I let the PV15 burn in for a few weeks before doing any serious listening, after which I was struck by the way it propelled the music into my listening room. It was very precise, methodical, and definitive in its delivery of music. In other words, with the PV15, there was a place for everything and everything was in its proper place. This preamp never allowed images to wander or widen beyond belief, never sounded larger or smaller than I was used to.
Another thing that jumped out at me was how little of that C-J golden glow, that burnished, lush sound quality that Conrad-Johnson products have always been known for, was to be found in the PV15. This was one of the most surprising things about the PV15. Ive heard enough C-J gear over the years to notice when a quality that has always been a hallmark is missing and replaced by a much more neutral sound. Oh, if you listen closely enough you can hear faint traces of that glow. Its just that now you have to concentrate to hear it.
Along those same lines was the PV15s way with frequency extremes. Sure, the midrange is to die for -- bloomy, slightly sweet. You should expect this quality from a good tube preamp, and the PV15 is a very good tube preamp. But I was more impressed with the way the C-J design team cannily handled bass depth and treble extension. Does the PV15 plumb the absolute depths? Probably not. Does its treble display ultimate prominence? Again, probably not. The PV15 does, however, go as low and high as cleanly and smoothly as my Magneplaner speakers allow. So, given the ancillary equipment with which the PV15 will most likely to be partnered, I seriously doubt that youll notice anything about either frequency extreme. Besides, if you really need more bass or treble energy, C-J makes preamps that will reproduce those very qualities -- for more money, of course. But for the majority of us, the PV15's highs and lows will suffice and then some.
The PV15 picked apart even the most challenging of mixes. I bought the new self-titled CD by local power trio Cellblock One. This is heavy-metal music at its most basic. Its written to be played loud, to assault the ears with volume, with little or no thought given to sonic purity. The group does record to analog, however, so they cant be all bad, right? Despite the music's chits in the debt column, the PV15 showed the ability to sort things out. I could hear the guitar, bass, drums and vocals as separate entities. Granted, there was little in the way of depth, and the sound was very compressed. Hey, the PV15 cant work miracles, but it made this music about as enjoyable as possible -- provided you like heavy metal.
The PV15 handled dynamic swings with ease. Listening to the new Szell Mozart Symphony No.28 [Sony Classical 82876-78765-2], which was remastered in DSD and Super Bit Mapped to CD, the PV15 showed that it has the ability to jump from soft to loud with nary a hiccup. It never ran out of steam, even during the toughest passages. This speaks volumes for the quality of the power supply with which C-J endowed the PV15.
Its way of delineating instruments was revealed when I slipped the new CD from the Classical Jazz Quartet, Plays Bach [Kind of Blue 10012], into the Stello CD player. Each of the four musicians stood apart from his fellows. There was plenty of space allotted to each instrument. This allowed the bloom of each instrument to show in all its radiance. All instruments were given the body and tone needed to allow me to close my eyes and become deeply immersed in the music. And that, my friends, is a very big deal in mid-level preamps. Some of them can limit dynamics, flatten images, and basically mess up the music. The PV15 not only doesnt do any of those things but truly enhances the enjoyment of listening.
Another aspect of the PV15 that stood out was its overall resolution. I finally obtained a copy of Colin Lindens album Big Mouth [Accord SACD S 6001]. Most of the songs were recorded in a variety of different venues. The PV15 easily conveys this. On "Dont Tell Me," I could hear that each musician had been recorded separately, and afterwards that collection of parts was pieced together in the studio. This could distract from the complete enjoyment of the CD. The PV15 managed to expose those diverse recording locations while still holding the song together enough to allow me to gain at least some modicum of enjoyment from the album.
Having such a resolving nature is something of a double-edged sword, though. On the one hand, all of the detail the engineer managed to record will be reproduced. On the other, the tight focus can, as in the case of "Dont Tell Me," momentarily distract you from the overall enjoyment of a particular cut. You dont get it all at this price point. When it's pushed a bit too hard, the PV15 can cause voices to become somewhat hard and brittle. Kept within proper, limits this wasnt a problem. If you like to listen at high levels, the PV15 may not be the best choice you can make.
Using the phono stage of the PV15 was a joy. It was quiet (a real plus for a tubed unit), displaying only a minimum of tube rush if I turned the volume all the way up. Most important, it makes good vinyl records sound like nothing else readily available to the consumer. To use that old cliché, the PV15 had me pulling album after album from my record racks to enjoy. No matter which album I chose, whether it was Cannonball Adderley or Lester Young, Bach or Mozart, Maria Muldaur or Johnny Winter, or the Beatles or Joe Walsh, the PV15s phono stage did right by it. Sure, I would have liked a tad blacker background, a bit more detail and a smidgen more incisiveness, but if youre looking for all those things, then youre someone who will be paying quite a bit more for a separate phono stage. However, if youre looking to trim the number of boxes in your audio rack, the PV15 is a full-function preamp that allows you to enjoy both your vinyl and CD collections.
The PV15 butts heads with the highly successful Audio Research SP16 ($2495 line stage only, $2995 with phono stage). Both are tubed units, both are remote controlled, and both have optional phono stages. Yet there are enough differences to make each desirable on its own based on both sonic and ergonomic strengths and weaknesses.
Thus, this comparison shaped up to be exactly what Ive already mentioned -- a battle of equals. Hey, thats what you usually get when you pit two evenly matched opponents against each other. The PV15 and SP16 are both fine examples of each companys musical ideals built to a price point that most aspiring audiophiles can actually reach. Both do a wonderful job of communicating the essence of the music. The SP16 sounds more like a classic tube unit brought up to modern standards, which means it sounds more gentle and rounded at the frequency extremes. The PV15 keeps some of that tube magic while adding some of the virtues of solid-state at the frequency extremes -- greater extension, less tubey softness. I could hear this whether I listened through the line stage or the phono stage.
I could live very happily with either, but as I listened to each one, I found that my decision would come down to ergonomic issues as much as to sonic ones. For me, the inclusion of the stereo/mono switch on the SP16 was of greater importance than the balance control of the PV15. You may feel differently. In a perfect world, each preamp would have both features, but sacrifices must be made and options chosen. Ive made mine, and youll make yours.
But dont pass up the chance to listen to both the C-J PV15 and the Audio Research SP16. Then get back to me with your choice and why you made it. Im willing to bet you won't have an easy time of it.
To say that the PV15 lived up to all my preconceptions about the sound of a Conrad-Johnson component would be incorrect. It surpassed most of them, sounding less C-J-like than perhaps all of its ancestors. It does many of the things that the very best preamps do at a price that wont have your spouse talking to lawyers. Its line stage is neutral and its phono stage is quiet. Both make for good sound from any source connected to them. No, the PV15 isn't a perfect preamp, as if that animal even exists, but it makes the most of its positive attributes. What it does mostly is make enjoyable music that will have you melting in your listening chair for years to come.
If youre ranking preamps in the $3000 price range -- and even somewhat above -- be sure you have the PV15 on your scorecard. It's a top contender.
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