PrimaLuna and I go way back; back before TONEAudio was even a twinkle in my eye back.  The first audio review I wrote for The Absolute Sound happened to be the original EL-34 based ProLogue 1, and was way more exciting than the boring NAD integrated amplifier that Robert Harley was going to have me cover for my first assignment.  I bought that review sample not only because it sounded great, but it was so much fun; reminding me of all the great EL-34 amps I’d owned over the years.  11 years later it’s still in my family, going strong, with merely one set of replacement tubes – a testament to PrimaLuna quality.

It’s been fun watching TONE and PrimaLuna grow over the years, diversifying our products, but keeping the same ethos of offering high performance at a reasonable price, never giving quality a back seat.  PrimaLuna now has a range of four vacuum tube preamplifiers; with the DiaLogue being the top of the range at $3,199.

Where a number of past PrimaLuna preamplifiers relied on the 12AX7 tube, the DiaLogue Premium takes advantage of the 12AU7, six of them – and this has two big benefits.  For those not familiar with the brand, PrimaLuna gear has always been super easy on tubes, so investing in a good set of premium NOS (New Old Stock) tubes has always been solid thinking.  Fortunately, where the best 12AX7s are now pushing $200 – $350 each, equally good 12AU7s will only set you back about $75 each.  And PrimaLuna’s US importer Kevin Deal can hook you up.

You don’t need to invest in NOS tubes if you don’t feel inclined.  The DiaLogue Premium sounds great out of the box.  Tube rolling is only for those who are part curious, part OCD, and can yield different results for those wanting to chase the rabbit.  Most of you will just unbox your DiaLogue Premium and enjoy.  There’s nothing wrong with that.

The biggest advantage of the 12AU7 though, is it’s lower gain.  With so many of todays sources having a four volt output, the 22 -28db of gain that most contemporary line stages provide is just not needed.  You end up with the volume control always being used in the 7:00 to 9:00 position and not only having precious little range of control, but noise can be an issue because the preamp is not running in it’s sweet (and lowest noise) spot.

Less gain, less pain

The DiaLogue Premium, having 10db of gain, gives you plenty of volume control range and is dead quiet throughout.  Using it with my Zu speakers (101db sensitivity) and a pair of 845 SET amplifiers, I had the silky smooth silent treatment, even with my ear right up against the ribbon tweeter.  When substituting the DiaLogue Premium, for the Nagra Jazz preamplifier in an all Nagra system, thanks to the low gain, the PrimaLuna was quieter than the mighty Nagra, costing three times more.

A dual mono design with five inputs and two variable outputs, the DiaLogue Premium should be able to handle anything you can throw at it, except balanced sources. (You can use an adapter if need be)  As a tape enthusiast, I really appreciated the additional, fixed level, buffered tape output to make mix tapes on my trusty Revox.  A home theater pass through is also incorporated, for those needing to make the DiaLogue part of a home theater system.

Running the DiaLogue Premium in our main reference system, displacing the $13,000 ARC REF 5SE preamplifier and the $32,000 Robert Koda K-10 was highly insightful.  While the big bucks preamplifiers revealed more music and more dynamic slam at the extremes, the mighty PrimaLuna was never embarrassed.  Kind of like comparing a Porsche Cayman S to a GT3.

Trying the DiaLogue Premium with about ten different power amplifiers from Simaudio to Burmester again underscored it’s versatility.  Only the Burmester 911 Mk. 3 really needed the volume control cranked all the way to get full output.  (no doubt because we were using balanced adaptors here, all of the other balanced power amplifiers tried had separate, single ended RCA inputs. That lower gain was a real blessing when using vintage power amplifiers like the Conrad Johnson MV-50, which only need about .6 volts to be driven to full output.  FYI, combining this preamplifier with my MV-50 that has had all of the caps upgraded to CJD Teflon was absolutely heavenly, mated with my Quad 57s.

I’ve always found PrimaLuna gear to be a wonderful combination of old and new school design and sonics, yet as you go up the line, the top components in the PrimaLuna line sound more like current vacuum tube electronics, i.e. more linear and neutral, where the entry level pieces sound slightly more vintage.  Much of this is due to the beefy power transformers used, combined with premium Takman resistors, SCR foil capacitors and Swiss sourced, silver plated oxygen free copper wiring throughout.

It’s also worth mentioning that the DiaLogue Premium has no problem driving long runs of interconnect cables.  Comparing the sound between a 20 foot run of AudioQuest (find cable here) and a one meter pair revealed no difference, and no rolling off of the high frequencies, so those that like having their power amplifier down on the floor close to the speakers, with the rest of their components further away on a rack will be pleased.  I had similar luck with cable from Cardas and ALO Audio.

Love that tube

Personally, there is always something special to me about the sound of a preamplifier built around the 12AX7 or 12AU7 tube, they just always seem to paint the sonic picture with a little bit more air and gradation than the 6DJ8/6922 designs do, and feature more sonic gradation between heavy and soft tones than a preamplifier utilitizing the 6H30 tube.  Neither is better or worse, just different.  A Lotus Elise gets around the curves with a little less effort than a Corvette or a Viper.

I noticed this the most when listening to acoustic music of any kind.  Spinning the XRCD of Lee Morgan’s Tom Cat, it was easy to discern the differences in rendition between my vintage ARC SP-11 (6922 design), current REF 5SE (6H30 design) and the Koda K-10. (best solid state I’ve ever encountered)  Morgan’s trumpet has more “blat” and slightly more contrast with the REF 5SE, but the cymbals are dreamier, more palpable, and smoother through the DiaLogue Premium.

Going back to some of George Winston’s solo piano records on the Windham Hill label, the pianos decay is equally enticing through the DiaLogue Premium.  This is a totally musical preamplifier, always getting out of the way of the presentation, so that you don’t focus on the gear.  Not all preamplifiers can do this regardless of price, so this is a home run for the PrimaLuna – and amazing for $3,199.

Each preamplifier brought its own palette to the reproduction, yet the DiaLogue offers an excellent balance, and cohesion to the musical presentation, almost like listening to a full range ESL, rather than a speaker made of woofer, tweeter and midrange.  The DiaLogue provides fatigue free listening at its finest, and made for many 12-hour listening sessions without wanting to ever turn the music down.

While the DiaLogue Premium turns in good performance at the frequency extremes, offering solid, defined and tuneful bass response, combined with extended highs that are never screechy, it’s this coherence and ability to nail instrumental tone and texture that makes it so compelling.

The DiaLogue Premium does what tubes do best, providing a dreamy, three dimensional sense of ambiance, giving the listener a healthy dose of “you are there” realism. Eschewing female vocals, I spent a lot of time listening to Johnny Cash, Elvis and Tom Waits through the DiaLogue Premium and I always came back impressed.  The soundstage painted is huge, in all three dimensions, making my Dynaudio Eminence Platinum speakers disappear in the room, no small feat.

Rounding the bases

The DiaLogue Premium preamplifier offers incredible sound and value for $3,199. If I were building a system in the $20 – $50k range, I can’t imagine needing to spend more than this for a linestage, provided you didn’t absolutely have to have balanced outputs.  The ability to tube roll with ease and modest cost is another big bonus with this preamplifier, allowing the ability to either fine tune the sound, or just play with a different feel.

Best of all in over a decade now, PrimaLuna has not compromised a molecule on build quality.  They are still making gear that feels bank vault solid, encased in a dark blue, high gloss metallic finish that would do an Aston Martin proud. (and a set of cotton gloves to keep fingerprints off of said finish)  Even the shipping cartons are the best in the business, with three layers of heavy cardboard to make sure your purchase arrives without blemish.

Combining all of these small touches and world class sonics, makes for gear that owners don’t want to part with.  Perusing Audiogon or EBay rarely reveals used PrimaLuna gear, and when it does go for sale, it fetches top dollar.  Another home run from PrimaLuna!

PrimaLuna DiaLogue Premium Preamplifier

MSRP:  $3,199

www.primaluna-usa.com

www.upscaleaudio.com

PERIPHERALS

Digital Source	dCS Vivaldi Stack
Analog Source	AVID Acutus Reference SP/TriPlanar/Lyra Atlas
Phonostage	ARC REF Phono 2SE
Power Amplifiers	PrimaLuna DiaLogue Premium Power Amplifiers    Burmester 911 mk. 3   Conrad Johnson MV-50C1    Nagra 300B    Pass Xs300    Pass Aleph 5
Cable	Cardas Clear
Speakers	Dynaudio Eminence Platinum,    Acoustat 2+2, KEF Blade

Seriously, the only thing I don’t like about PrimaLuna gear is lifting it. Recent hours at the gym notwithstanding, PrimaLuna amps keep getting heavier. Continuously improving the breed, the Dutch company keeps improving the quality of it parts, which results in bigger capacitors and beefier transformers. The DiaLogue Premium power amplifier now tips the scale just over 70 pounds. Yikes! But listening to Miles Davis’ classic album Bitches Brew float between the Focal Maestro Utopias (also reviewed in this issue), I’m not worrying about moving these amplifiers anymore. The relaxed yet resolving presentation the DiaLogue Premium amplifiers provide is sufficiently soothing to take my mind off of the manual labor.

For those of you who are unaware, my journey as an audio writer began with PrimaLuna. My review of the ProLogue One integrated amplifier was featured in The Absolute Sound just over 10 years ago. Time flies when you’re having fun. I bought that little integrated that could, and a decade later (on only its second set of power tubes), it still can. It’s been passed on to my niece, and she’s still rocking out with it after all these years—a testament to the build quality and longevity of PrimaLuna products. Best of all, the company is building the stuff even better than when I bought that review sample, so your chances of a field failure are slim to none—a great feeling when you’re shelling out close to $10,000 for a preamplifier and a pair of monoblocks. The DiaLogue Premium amplifiers are $3,199 each, and the preamplifier will also set you back $3,199.

They’re not quite the budget components that they were in 2003, but in comparison to your favorites from ARC, CJ, McIntosh and VAC, they’re still an incredible bargain for the price asked. Those nervous about PrimaLuna being a new company back in 2003 can breathe a sigh of relief. There is now no question that the company has been making all the right moves in terms of building an empire.

The DiaLogue Premium amplifiers are especially cool, because you can start with just one and run it in stereo. Should you want or need more power, add a second amplifier, flip the stereo/mono switch on the back panel and you’re rocking. A single amplifier produces 42 watts per channel in ultralinear mode and 25 per channel in triode mode. Switching to monoblocks doubles that, making this amp a nice option for budgeting future system upgrades.

The Magic of the EL34

The enchanting midrange of that first PrimaLuna amplifier always gave me pause, thanks to the EL34 output tubes, but 30 watts per channel isn’t always enough to take care of business. Fortunately, the DiaLogure Premiums give you a choice of 82 watts per channel in ultralinear mode or 50 watts per channel in triode mode, configured as monoblocks.  And there’s just something so scrumptious about using these amplifiers thusly. I suspect you may just seek out slightly more sensitive speakers so that you can always do so.

While 50 watts per channel is enough to adequately drive my 90-dB KEF Blades, the additional 3 dB of sensitivity provided by the Focal Maestro Utopias is just enough to really give the DiaLogue Premiums in mono mode that extra push over the cliff and make them that much more compelling. In the context of a system consisting of a dCS Vivaldi stack, Audio Research REF SE linestage and phonostage, along with a pair of AVID Acutus Reference SP turntables, the DiaLogues are in some pretty exclusive company. And they fit right in.

The delicate acoustic guitar at the beginning of the Verve Pipe’s “Colorful” is projected well beyond the speaker boundaries, but when the driving bass line kicks in, these amplifiers take impressive hold of the Maestros’ woofers. All this from a pair of EL34-powered monoblocks is indeed impressive.

A quick switch back to ultralinear mode delivers tighter bass, but at the expense of less midrange delicacy; the ultimate choice will be yours, but I know what I love and it’s all about the midrange with these amplifiers. Whatever your reason for going ultralinear, should you decide that is your path, go all the way and replace the EL34s with a set of KT120s. Even though the power rating is no higher, a simple flip of the switch on the right side of the amplifier resets the Adaptive Auto Bias to the correct range for this tube, eliminating potential midrange distortion. The KT120 tube has a more authoritative feel, with a deeper, tighter bass response. Overall, the amplifier has more drive and slam, feeling more like an Audio Research REF amp. Running the EL34s in triode mode makes the DiaLogue sound more like an AirTight amplifier.

Listeners who find tube amplifiers too relaxed in their presentation may think these amplifiers in triode mode are even slightly more relaxed. But this sonic characteristic works wonders when listening to recordings that are less than perfect—like my favorite records from the Monkees. “Pleasant Valley Sunday” is pretty much rubbish, but the extra sweetness that the DiaLogue Premium brings to the dance really improves recordings like this (especially in digital form), making a much larger percentage of your music collection not only listenable but enjoyable. There’s no such thing as listener fatigue with these amplifiers.

Changes Under the Hood

PrimaLuna has always paid meticulous attention to detail when building its amplifiers, which are reminiscent in quality of the great Marantz and McIntosh tube amplifiers from the 1960s. The point-to-point wiring used throughout is so neatly done that you’d swear robots did it, but this is not the case. The solder joints are all perfection and there is not a hint of untidiness anywhere. These amplifiers are as beautiful underneath their hand-finished chassis as they are above.

In addition to bigger, beefier, more robust power and output transformers, the “premium” designation comes from careful refinement of the circuit, which was executed with top-quality parts—parts you’d expect to see in amplifiers with five-figure price tags. All of the critical wiring is done with Swiss-made silver-clad oxygen-free-copper wire, the input and output connectors are first rate, and there is a plethora of premium capacitors and resistors. No corners have been cut anywhere.

And what fun would a vacuum-tube amplifier be without at least considering a bit of tube rolling? This is a bit tougher with power tubes these days, as vintage EL34s can be difficult to find, and expensive when you do find them. It’s not uncommon to spend $400 to almost $1,000 on an awesome set of NOS output tubes. Rolling in a set of Siemens and GE 6CA7s (a suitable substitution) proves sweet, eliminating grain from the presentation of the upper registers in a way that today’s modern tubes just can’t.

Fortunately, the DiaLogue Premium runs the output tubes very conservatively, and thanks to PrimaLuna’s patented Adaptive Auto Bias, adjusting tube bias is a thing of the past. The benefits are multiple: Tube life is extended, distortion is reduced, and the need for a matched quartet of output tubes is eliminated. It’s as painless as it gets for a vacuum-tube amplifier. There is even a Bad Tube Indicator, a red LED that lights up, should an output tube fail.

However, if you aren’t feeling that adventuresome but still want to get in on the action, consider swapping the small signal input tubes. Past PrimaLuna designs used at least one pair of 12AX7 tubes, which are now becoming scarcer, and consequently more expensive. A single pair of primo vintage 12AX7s can set you back $300 to $400, but this amplifier uses six 12AU7s. And these tubes are reasonable, with cool vintage examples available for $30 to $50. But remember, standard new-edition 12AU7s are only about $20 each. Either I’m getting lazy in my old age, or Kevin Deal is supplying these amplifiers with even better tubes than he was 10 years ago. In any event, I just don’t feel the need to screw around with the tubes here.

True to the PrimaLuna party line, the Adaptive Auto Bias will let you run different tube types in the various output tube sockets, but having lived with PrimaLuna amplifiers for a long time, I know that they just don’t eat tubes, so you’ll probably never need to take advantage of this feature. Sure, it does work, but if you have a tube amplifier of any kind, it’s not a bad idea to have at least a pair of output tubes of the same type on the shelf, just in case something bad does happen.

Once hefted into place and tubes installed, the DiaLogue Premium amplifiers immediately settle into reproducing music. The harp in Lloyd Cole’s “Music in a Foreign Language” floats easily behind the plane of the speakers, sounding almost like it’s in another room, well separated from Cole’s voice and acoustic guitar. Even in the 15 minutes it takes for these amplifiers to warm up, the magic is there. Unlike a few megabuck tube amplifiers we’ve used that take hundreds of hours to sound their best, we only noticed a modest change in sound character after about 50 hours. And had we not had a pair of these, so that one could run for 50 hours while the other one just sat there, we’d never know—the difference is pretty minimal. Bottom line, unbox these beauties and enjoy them.

Grab a Pair

If there’s been a better success story than PrimaLuna in the high-end audio market over the last decade, I haven’t heard it. The Dutch company continues to make top-notch products, while refining its brand and expanding its current offerings.

If you’ve ever felt intimidated by using a vacuum-tube power amplifier, PrimaLuna takes all the hassle and guesswork out of the process. The more adventurous hobbyists can tube roll to their hearts content, and the rest of you can just use the supplied tubes and dig the music.

We are happy to award the PrimaLuna DiaLogue Premium amplifier our Product of the Year award in the tube-amplifier category. A most excellent amplifier—and I suggest you get two while you are at it.

DiaLogue Premium amplifier

MSRP: $3,199 each

www.primaluna.nl (factory)

www.primaluna-usa.com (U.S. distributor)

Peripherals

Speakers	KEF LS-50    KEF Blades    Focal Maestro Utopia
Analog source	AVID Volvere SP turntable    SME 309 tonearm    Lyra Kleos cartridge
Digital source	OPPO 105    dCS Vivaldi stack
Preamplifier	PrimaLuna DiaLogue Premium    Robert Koda K-10    Audio Research REF 5SE
Phonostage	Simaudio MOON 610LP
Cable	Cardas Clear
Power	Cardas Clear    Running Springs Dmitri