PrimaLuna DiaLogue Three preamplifier

At what point does a domestic audio product cease to be an appliance and assume a loftier place in one's home and heart?

We all can agree that a Bose Wave CD player sits at one end of that continuum, a Koetsu Jade Platinum phono cartridge at the other—but what of all the products in between? Scarcity, mode of manufacture, appearance, even sentimentality ("This is just like the one my father used to have!")—each plays a role, but there's no doubt that price tops the list: The more we pay, the more we love (footnote 1).

If we remove price from the equation, what then? Is sheer quality enough to tip the balance? Given the availability of audio goods designed in America or Europe and manufactured in the Far East, the answer may already be at hand: Although hand-wired vacuum-tube electronics have long been among the most cherished audio heirlooms, those sorts of thing are now available at popular prices, as the saying goes.

Consider PrimaLuna, who design preamplifiers, power amplifiers, and integrated amplifiers in the Netherlands, and manufacture them in their own factory in the People's Republic of China. Far from being just a me-too maker of undistinguished gear or—worse still—a forger of other people's designs, PrimaLuna has impressed me and other reviewers with their innovative circuits and very high build quality, not to mention a level of performance that, nuances aside, can be summed up in three beautiful words: classic tube sound. Thus, when John Atkinson asked me to audition their new top-of-the-line DiaLogue Three preamplifier ($2599), I was, as they say, all over it.

Description
The first thing I noticed about the DiaLogue Three—before the nice paintwork, before the point-to-point wiring, before the sound—was its considerable weight: 53 pounds of iron, steel, and copper, not to mention all those vacuums. This preamplifier weighs half again as much as some of my favorite tube power amplifiers, and three times as much as my dog.

That's because the DiaLogue Three is designed and constructed as a dual-mono preamp—all the way through, including the power supply and, unusually, the mains transformers. Said trannies appear to have been made specifically for the Three, and are protected with a circuit that detects excess heat and temporarily interrupts the primary feed, should things require cooling down. Shoppers in hell, take note.

The DiaLogue Three is housed in a steel chassis whose shape also calls to mind that of a classic tube amp. A vented transformer cover towers over the rearmost portion of the low-slung surface, the latter interrupted by six tubes: two rectifiers and four dual-triodes. The tubes are protected from the user, and vice versa, by a removable cage shaped like a roll-top desk's most distinguishing feature, and the front of the chassis is fitted with a modestly sized faceplate. The latter is aluminum alloy with a satin finish, while the remainder of the DiaLogue Three is painted with five coats of hand-rubbed blue-gray lacquer. (Black is also an option.)

The preamplifier circuit is straightforward: In each channel, the line-level input signal is conducted, by means of a shielded cable, to the signal grid of a 12AU7 dual-triode tube, the two halves of which are operated in parallel. The ganged plates of that tube are tied, via a Solen capacitor, to the input of a motorized Alps Blue Velvet volume pot, the output of which is sent to the signal grid of a second 12AU7, also operated with its two halves in parallel. The plates of that tube are capacitively tied to the output jacks . . . and there you have it. Except for that very last connection (the printed circuit board for the power supply is also home to the chunky Solen signal-output caps), the preamp section is hand-wired, point to point, with liberal use made of nice-looking ceramic terminal strips, which are cemented to the inside of the chassis.

The DiaLogue Three's power supply, which is constructed using both point-to-point wiring and the remainder of that PCB, uses a single 5AR4 tube for the rail voltages of each channel. Filament voltages for the rectifier tube are supplied by dedicated secondaries of the mains transformers, while full-wave rectifiers constructed with discrete diodes are used to heat the signal tubes.

A modestly sized solid-state preamp board ($199) can be used to change one of the DiaLogue Three's inputs to a moving-magnet phono input, but that option wasn't provided with my review sample. As typically supplied, the preamp's rear panel has five line-level inputs, two system outputs, one tape-monitor output, and pass-through jacks for driving a surround-sound device in a home-theater system. The front panel sports only a volume knob and a source-selector knob, which of course prompted my usual teary whine: I wish the PrimaLuna had a balance control and, especially, a mono switch. I would happily trade that surround-sound thing for the latter.

Included in the price is a remote-control handset that incorporates all the user controls for this and, apparently, all other PrimaLuna products—including the Triode/Ultralinear mode switch for the DiaLogue Seven power amplifier. The handset is built into a chunky aluminum-alloy housing of reassuring heft, although a seam between the two halves of the housing had an edgy feel that, in time, discouraged me from using the remote. (I needed the exercise anyway.)

The DiaLogue Three's external fit and finish were very good, and its internal build quality was nothing short of magnificent.



Footnote 1: That, of course, is a sliding scale unto itself: To the consumer of comfortable means, a $500 record player might be little more than a commodity, while the person who's saved for months or even years to buy such a thing would think of it as a cherished possession, and rightly so.
Company Info
Durob Audio BV
US distributor: PrimaLuna USA
2504 Spring Terrace
Upland, CA 91784
(909) 931-0219
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Comments
Hoser Rob's picture
SoftStart?

Hmmm ... that sounds just like tube standby mode to me.

I applaud the fact that they have a standby mode, and that it's automated, but it amazes me why that's not more standard nowadays.  It used to be.

And with the quality of today's tubes it should be standard, especially for power amps.  Not preheating the filaments really decreases tube life.  I can't believe how much costly tube gear doesn't do this.

maury's picture
Can't Wait!

I just ordered one of these, along with the DiaLogue Severn Monoblocks. They'll be here next week, but I still have to get my speakers here so I can't try them yet!

Pete's picture
Question for Art Dudley

Hi there.

Thanks for the honest review.

But why do you compare so speciffically to a pre amp 4 to 7 times the price? Wouldn't it be the same to compare it to an amp of say $400,00?

And then stating the differences?

In this way, allthough I insist on honesty and realism in audioreviewing, I always get the feeling that it is still not a very good amp. That it is 'only mid range' you will buy. Or am I the only one that feels that?

Why not compare this 2,6k amp a little bit more to Tube Pre Amps of about 2 to 4k? Or heck: even up to 6 or 7k? Instead of 10 to 18k? More from an upgrader's perspective?

Of course we still all do want to know how it compares to 10 to 18k amps... But the remark about the bass remains a bit unfair I think.. Even if you 'haste to remind'... It sticks with me anyway.

Because I look for an upgrade! I come from 'lower'. I have a top class Tentlabs cd player of $4600 (please do review sometime!) and a Power Amp of about $3300.

My Pre Amp is a modified Rotel RC 995 of about $1000. So although this thing is still surprisingly good, it's still also my 'bottleneck'. I know I have some very top class speakers allready too and my room and setup are other topics of course (not bad at all).

So I'm looking for a Pre Amp upgrade: say about $2600! So I want more comparison to 2-4k amps, not speciffically to 10 or 18k amps, reviewing a 2,6k amp... 

Allthough it's a fair remark and I'm sure you meant that it is very good at it's price (which you also stated..), in my humble opinion you still end the review with a touch of 'looking downward' on this amp.. And I don't say that because I'm dutch just like the amp... But because I'm 'looking upward'...

Anyway. You're not a salesperson for Prima Luna (neither am I). So thanks for the effort and for the honest information.

Maury: how are they?

Et Quelle's picture
Dialogue 3

This thing is good looking for a pre-amp under $3,000. Why do others look like small simple metal boxes with tubes on top; AVM looks average though. If stereophile raves over it, then it I trust their opinion even though I would jump at the chance of an audition at a dealer. That tells you a lot, but half of what it will sound like with my interconnects, non thousand dollar speakers and components. The only way is to buy everything in the artice (a dream) or just buy the Dialogue 3 and see.

DLKG's picture
Prima Luna pre amp vs integrated

I hope you answer this question.  Why is it that you can get an integrated Primaluna for only a few hundred dollars more than the pre amp alone?  I've also read rave reviews about the integrateds but would I be better off with the pre amp and using my existing (Hafler Transnova)?  I guess I'm finding it hard to believe that a pre amp with a few hundred dollar amp section could be as good as a separate amp even though it's really old.  Primaluna price points makes things very confusing.  Not just that but the fact that I have not found. A dealer where I can compare the integrated and the pre amp with a separate amp.  

 

DLKG

myvpi@aol.com

 

 

 

 

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