Integrated Amp Reviews

When I compared the ProLogue Premium with the CD-player interconnects plugged directly into its CD inputs vs into one of the CAT's line-level inputs, the output of the CAT driving the ProLogue's amp section directly, the differences were not great but were significant. The tonal balance remained much the same, but with the CAT doing the preamplification there was a definite improvement in what I might call finesse—the percussion instruments in track 3 of the Chesky test CD were clearer and more distinct, but also more delicate, and with no added edge or harshness. Double-bass notes were also more clearly defined. Bass drums had greater weight. Given that the CAT SL-1 Renaissance is widely recognized as one of the world's best preamps, and costs nearly four times as much as the ProLogue, the fact that it sounded better than the Premium's preamp section shouldn't come as a surprise. The real surprise is how close the ProLogue's preamp section came to the sound of the reference-quality CAT SL-1.

Sound: More Exotica
As I neared the end of my time with the ProLogue Premium, a pair of MartinLogan Montis speakers arrived for review. The Montis ($10,000/pair) features an electrostatic midrange/tweeter mated to a powered woofer. Electrostatics are notorious for presenting a difficult load to amplifiers (the specifications for the Montis state that its impedance at 20kHz drops to 0.52 ohm), but having a woofer with its own amplifier should help.

Since the ProLogue Premium was the first amplifier I used with the Montis, I had no background to draw on to determine if, in fact, the ProLogue was a good match for this speaker, but it sounded pretty good to me. Mark Aling of Paradigm/MartinLogan, who helped me set up the Montises, and who has heard them in other contexts, indicated that he was pleased with the sound. Whatever the effect of the low-impedance load in the high treble, the ProLogue Premium didn't seem fazed by it—perhaps because there's so little musical content up there. A test with the CAT-Audiopax quickly revealed that this was not a good combination: the treble was much softer than ideal, and the amp ran out of steam at higher—but not room-shaking—levels. The ProLogue Premium fared better; the highs were still a bit subdued, but to a lesser extent.

As mentioned earlier in the review, my listening throughout was with the EL34 output tubes. When I had the GoldenEar Triton Twos in the system, I did a brief trial using the KT88s, and I much preferred the EL34s' more laid-back sound. The ProLogue Premium's rated output using the EL34s is 35Wpc, whereas with the KT88s it's 40Wpc—a difference small enough that I thought it would be inconsequential. Nevertheless, I swapped out the EL34s for KT88s (remembering to change the position of the bias switch), and, whether because of the minor power difference or other reasons, I preferred the sound with the KT88s. Unlike with the Triton Two, where the sound with the KT88s was a bit on the brash side, with the Montis the sound was tonally better balanced than with the EL34s, with more extended highs and a more dynamically lively presentation.

My last comparison involving the Montis and the KT88-equipped ProLogue Premium involved changing from the 4 ohm to the 8 ohm speaker connectors. The Montis is rated at 4 ohms, but is described as being "compatible with 4, 6, or 8 ohm rated amplifiers." I fully expected that the 4 ohm output would produce better results, as it had with the Triton Two. Not so! The sound using the 8 ohm connectors was more open and better focused.

It just goes to show you that in audio there's little that you can take for granted. With the KT88s and the 8 ohm speaker connectors, the combination of ProLogue Premium and MartinLogan Montis became a more-than-credible match, despite the major disparity in their prices.

Conclusions and System Building
Built to a high standard, the PrimaLuna ProLogue Premium offers outstanding sound quality at a very reasonable price. In my listening tests, it combined well with speakers both conventional and exotic, and gave high-end references more than a run for their money.

Audiophiles often complain about how expensive this hobby has become—and not without justification. In apportioning the job of reporting on amplification components at the 2012 Consumer Electronics Show, Larry Greenhill and Stephen Mejias set $5000 as the dividing line between "inexpensive" and "expensive." (Stephen tells me that he would have liked to set the cutoff at $1000, but there simply wasn't enough at CES below that price, which would have led to an unequal division of labor.) The 2012 Stereophile Buyer's Guide lists 29 integrated amps costing $10,000 or more, including one that comes in at a cool $100,000. Is this sheer madness?

What tends to be forgotten during the expressions of outrage about high prices is that if you ignore equipment at "crazy prices"—and, of course, each of us has his or her own idea of exactly where "craziness" begins—ours is a great age for the cost-conscious audiophile. If you do your homework on what's available, read the reviews, and visit dealers who make a point of offering their customers value, you can assemble a system for a reasonable price that—with attention paid to component matching and setup—can offer sound quality that comes close to the cost-no-object.

The ProLogue Premium would be an excellent component around which to start assembling such a system. I found it combined well with speakers as disparate as the Avantgarde Uno Nano, GoldenEar Triton Two, and MartinLogan Montis. The ProLogue Premium also allows some fine-tuning to match the speakers: there's a choice of output terminals (8 or 4 ohms), switchable power-tube bias, and a choice of power tubes (EL34 or KT88).

Playing the system-building game, first with an emphasis on keeping the total system price down, I would combine the ProLogue Premium ($2299) with the Marantz CD5004 CD player ($350), and with something like the Dynaudio Excite X12 ($1200/pair) or PSB Imagine B ($1100/pair) speakers, plus some entry-level cables from AudioQuest or Kimber Kable. At a total price of around $4000—plus another $400 for a Pro-Ject Debut III turntable and $199 for the PrimaLuna phono stage to get you into the world of vinyl—you'd have a musically satisfying system that represents outstanding value.

At the next system price level, the obvious partnering loudspeaker for the ProLogue Premium is the GoldenEar Triton Two. Keeping everything else the same, you'd have a system price of about $6000. Further improvements could come from upgrading the digital source (I'd first check out Oppo's BDP-95 SACD/CD player, for $1000)—and consider getting better cables and a power-line conditioner. For a total price well under $8000, this system could easily compete with the typical rig costing $20,000.

Yes, this is a great time to be an audiophile.