The original PrimaLuna integrated amps, the ProLogue One and Two, have reached cult status and are now a collectible that will no doubt be iconic in the years to come. Some are going so far as to call them "The Marantz 8B of our time". The multi-award winning ProLogue One was in a recommended system called "Tube Nirvana" by The Absolute Sound's Robert Harley. Stereophile's Art Dudley stated "Lustily, heartily, and enthusiastically...recommended." The ProLogue Two was loved the world over in review after review.
If something works, don't fix it. But there were still improvements that could be made. PrimaLuna engineers in The Netherlands went to work to make this the new classic.
The ProLogue Classic Integrated brings you to a world of glorious tube sound and superior engineering and quality.
Wide-Bandwidth Output & Toroidal Power Transformers
250 watts of power will have no top and bottom extension if the output transformers don't have enough bandwidth. PrimaLuna uses lower power to extend tube life, and bandwidth to give you slam. Their output transformers are custom wound in-house for deep and tight bass extension, an extended top without even a hint of grain, and the famous PrimaLuna midrange.
Unlike standard EI power transformers, toroidal transformers don’t radiate a magnetic field, which can is easily detected in preamp circuits as low-level "hash". Although expensive to manufacture, PrimaLuna power transformers are built huge and rated for 200% of their duty cycle. PrimaLuna transformers are also potted and enclosed to protect the windings from moisture and deterioration forever.
Bad Tube Indicator
PrimaLuna engineers wanted to make owning a tube amp so simple you would have no excuse not to have your tube dreams come true.
If a tube fails, Adaptive AutoBias will instantly put the amplifier into protection mode so no parts can get damaged. A red LED will light up in front of the tube that needs replacing. (ProLogue Classic illuminates an LED on the front panel.) Simply plug in another tube, and listen. No guesswork. No smoking amp. No getting out the soldering iron or dropping your amp off at UPS.
What most companies call Auto Bias is actually "Cathode Bias"- A commonly used method that is cheap to make, and often found in guitar amps, but also $20,000 high end audio amps. It reduces the available power of the amp and runs the tubes hard, meaning shorter tube life and failures via "shorts".
PrimaLuna's Adaptive AutoBias is a true, smart technology employing an array of sensors to monitor tubes and make adjustments seamlessly in real time. Adaptive AutoBias is completely passive and NOT in the signal path. The result is low to no maintenance, long tube life, and the lowest possible distortion for amazing sound.
Adaptive AutoBias also provides unparalleled flexibility by allowing use of almost any tube on the market today.
SmartWatts - Extended Tube Life
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: 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. PrimaLuna proudly tells you their tubes run at just about 417 volts for the plates and screens.
PrimaLuna runs their output tubes at a minimum dissipation without going into crossover distortion. When you look at their 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. 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 they didn’t stop there.
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.
Point to Point Wiring
You spend a lot of money on interconnects. So why have the signal go right from the RCA jacks or speaker terminals into circuit boards with copper traces so thin you can hardly see them? What’s high-end about that
PrimaLuna employs Point to Point Wiring on all products. The entire signal path, including resistors and capacitors, is painstakingly hand wired with heavy-gauge cable by craftsman.
PrimaLuna Amps Are Perfect. But Your System May Not Be
Ask any seasoned tube-head what the most musical output tube is and they will most certainly declare it the EL34. Other amp manufacturers would love to use it. Only PrimaLuna, through their proprietary output transformer designs, can give you EL34 midrange beauty with top-end air that goes on forever. And, bass extension with so much slam, their amps are used to power subwoofers.
However, every system is different. What if you bought a speaker with bass that overloads the room? Or, that is too dark? Or, too bright? What if you just want to have fun trying the different colors of sound from a vast pallet of tubes? With other manufacturers' products, you're stuck. They're a one-trick pony. How are you going to fine-tune your sound? Buy some different cables?!
With PrimaLuna, you get to choose. Go for it. 6L6G, 6L6GC, 7581A, EL34, EL37, 6550, KT66, KT77, KT88, KT90, KT120 (ProLogue Classic is not KT150 compatible). A future-proof design, PrimaLuna is compatible with NEW tube types not even thought of today!