ProLogue Premium Monoblock Amplifier - $4399/pr

The critically acclaimed PrimaLuna monoblocks just got better! By incorporating the best elements of the critically-acclaimed ProLogue Six and Seven monoblocks, plus many of the ground-breaking features from the more advanced DiaLogue Series, the next generation ProLogue Premium Series, is an engineering marvel — tube monoblock amplifiers that sets a new benchmark in high-performance audio with the following features:

  • Primaluna's exclusive Adaptive AutoBias. Bias is very important, and before you buy anything you need the click that link (it's in red) to learn the basics. If anybody tells you that they have auto bias, ask them precisely how. It's 99% likely to be untrue. As with all PrimaLuna amps, you never have to worry about biasing your amp ever again, and the need for matched tubes is eliminated. You can run EL34, KT88, KT120, even KT150 tubes, as well as many others. AAB does the rest while improving sound quality. Tubes are constantly monitored and kept in their best operating range, reducing distortion by up to 50%!

  • Custom wide bandwidth output transformers No other brand can copy the PrimaLuna sound for one simple reason: PrimaLuna output transformers. Almost every manufacturer buys their output transformers off the shelf; with varying degrees of success. Transformers are the most important (and most expensive) ingredient in making an amplifier. Our output transformers are custom wound in-house. The designs are the result of collaboration between engineers in the Netherlands and the United States, and built to the same standards that you come to expect from the world’s authority on tube amplifier manufacturing.
    That’s why PrimaLuna bass extension is deep and tight, the top end extended but without even a hint of grain, and that famous PrimaLuna midrange, which creates a sense of space and shape you won’t get anywhere else.

  • KT150 Compatible and designed for the future – In 2006 PrimaLuna introduced the original DiaLogue series; the first amplifiers designed to be as close to being future proof as humanly possible. Back then nobody imagined a tube like the KT120, let alone the KT150, which combines the sweetness of a 300B with bass and control never seen before. Now other companies are scrambling to make a product built to handle the demands of this incredible tube.

    All PrimaLuna DiaLogue Premium and ProLogue Premium amplifiers and integrated amplifiers are built with huge power transformers and filaments supplies needed to run KT150 tubes. And the ingenious design of our exclusive Adaptive AutoBias circuit means that PrimaLuna buyers from ten years ago don’t have to sell off their system to enjoy new tube developments.

    No planned obsolesce. Isn’t that a refreshing concept? And while we can’t guarantee being future-proof, we seem to have done a good job thus far.

  • Zero negative feedback - as with the ProLogue Series power amplifiers, the ProLogue Premium Power Amplifier uses a zero negative feedback topology for greater tonality and better overall musicality.

  • SmartWatts design with a tube life of up to ten years. When you buy any tube product, you need to think about the operational costs to own it. Many brands quote changing power tubes after 2000 hours. Not PrimaLuna. If an amp runs the tubes hard, its sound quality can start to degrade in 9 months and need to be re-tubed in a year. What’s fun about that? Understanding tube life is easy when you understand this.

    Click Here to Read More About SuperWatts

    Tube life is simply a matter of how hard you run the tubes. That’s it. The only way to extend tube life is to run them as close to zero as you possible can, making sure it is not so low you go into crossover distortion. The life of a tube will depend on two things:

    1. Plate and screen voltage. If the plate and screen voltage is high, you are more likely to get tube shorts when you turn the amp on and you get cathode stripping which greatly effects the cathodes ability to spit out electrons. Manufacturers that run the hell out of tubes to pump up their power ratings will never tell you what voltages they use. They’ll say it’s “proprietary” as if it’s some secret sauce. There is no such thing. But if they told you that they used 575, 600, or even 625 volts you probably wouldn’t buy.

      No secrets here. We proudly tell you our tubes run at just about 417 volts for the plates and screens. This greatly reducing the chance of a shorted tube sending your amp off on a trip to the shop (Remember, PrimaLuna’s Adaptive AutoBias has a circuit that protects against tube shorts, not seen anywhere by any manufacturer). Cathode stripping is reduced because the plate and screen voltage is low, and because our SoftStart circuitry ramps up voltage slowly.

    2. Bias setting of the tubes. Bias is like setting the idle on a carburettor. The higher the tube is idling, the hotter it is and the shorter the life. Tubes can be run all the way to “Class A” which by definition means hot. We bias our tubes cool. You can sense it when you hold your hands over a PrimaLuna and compare it to a competitor. The PrimaLuna generates less heat.

    PrimaLuna runs their output tubes at a minimum dissipation without going into crossover distortion. When you look at our amps, they provide less power from each tube. With KT-120’s as an example, a PrimaLuna will give you only 21 watts per tube. So running a pair of them you get 42 watts. That’s a lot of power, but the demands per tube are a fraction of some manufacturers that give you 100 watts from a pair of KT-120’s. It’s a cheap way to get big power, and it’s cheap. In fact, free. That’s why it’s something that’s common in guitar amps, and sadly adopted in high end audio somehow. The birth of PrimaLuna HP. To get more power the right way is expensive. It requires bigger transformers, sockets, wiring, resistors, capacitors, and the tubes to do it. Which is exactly what PrimaLuna did. But we didn’t stop there. We added a second Adaptive AutoBias board.

    Read this carefully: Power has nothing to do with sound quality. Or bass slam. You can buy a 200 watt receiver for $299, and it will even have surround sound. Do you think for a minute it will sound better than a 50 or 100 watts high end amp costing $10,000? Of course not. Only first-time buyers think that way. Experienced audiophiles know that for the majority of listening sessions, you use maybe 10 watts of power.

    So are we exaggerating when we say up to a ten year tube life? Absolutely not. We have customers with PrimaLuna’s that have been getting regular use for well over ten years, with their original tubes, all the time. What’s ironic is our design philosophy had never been done in high end before, so we really didn’t know how far the improvement in life could go.

    This is what we found:

    A customer from Los Angeles, California named Les, bought an entire PrimaLuna system with pre-amp and monoblock amps, and had a home theatre installer wire it into his home. The installer knew nothing about tubes, and told Les that the system would sound better if he never turned it off and let it run 24 hours a day. Les did just that for over SIX MONTHS before calling us to ask if it was OK. We told him firmly “NO, and by doing the math found he had over 5000 hours on his tubes. He bought a new set and we offered to test his tubes to see if anything was worth salvaging. What happened shocked even us: With over 5000 hours, the power tubes tested at 90% of their original measurements!

    We recently had a customer get over 12,000 hours from a set of tubes. Even the power tubes! Using the factory figures from other brands who quote an average power tube lifespan of 2,000 hours, that same customer would have re-tubed six times!

    This is exactly why people rarely sell a used PrimaLuna. After such a great experience, they may buy another one, but it’s hard to let go of something that works so perfectly, gives so much joy, and asks for so little in return.

  • Panel mounted ceramic tube sockets and rear jacks. Some brands will mount tube sockets or hook up jacks to a printed circuit board. As the product ages, these boards can crack by simply changing tubes or cables. All PrimaLuna products mount ceramic tube sockets to a stand off, and the rear panel jacks are secured directly the the chassis.

  • Point to point wiring and premium parts. The ProLogue Premium is a work of art with internal construction you won't find elsewhere. It takes more time to build, and is assembled buy artisans, but it is built to last a lifetime. We beautiful smooth midrange use Solen capacitors made in France and for great bass large Nichicon capacitors.

Next, the ProLogue Premium Series introduces four innovative circuits that protect the amp at every level:

  • BTI-circuit. BTI stands for "Bad Tube Indicator." On the chassis’ deck in front of each power tube, is a small LED that lights up if the tube goes bad. The circuit then puts the amp into protection mode. With other brands, this may be when you have to break out the soldering iron to replace a plate resistor, and replace two or four tubes because your amp requires matched sets. With PrimaLuna, you just replace the tube it tells you to (no matched tubes required), and turn the amp back on. No hassles, no headaches.

  • PTP-circuit. If the power transformer should overheat, this "Power Transformer Protection" circuit cuts primary power, allows the amp to cool down, then resets itself.

  • OTP-circuit. The "Output Transformer Protection" circuit protects the output transformers in the event of a massive tube failure or user error.

  • +B relay. Replaces the plate fuse and works in conjunction with the OTP-circuit to protect the amp against tube failure. This method is less intrusive sonically and the relay resets itself once the faulty tube is replaced.

All packaged in a heavy steel chassis using five coats of high-gloss, hand-rubbed finish.  Silver or black face plate available.  

Owner's manual

To Get a Closer Look Inside, Click on the Red Boxes


Output: 70 watts x 2 EL34 or KT88, 80 watts x 2 KT120, 90 watts x 2 KT150
Freq. Response: 20Hz-85kHz +/- 0.5dB
THD: Less than 1% at full power
S/N Ratio: 101 dB
Input Sensitivity: 911mV
Power Consumption (per amp): 210 watts
Dimensions: 14.5 " x 8" x 15.5" (WxHxD)
Weight (per amp): 46.3 lbs
Inputs: 1 each RCA
Outputs: 2, 4 and 8 Ohm speaker taps
Standard Tube Compliment (per amp): 4 - 12AU7, 4 - EL34