We don’t want you to compare the ProLogue Premium to an integrated that sells for $2399. That’s too easy. We want you to compare it to an integrated that sells for $5000. Compare it for the things that really count. Build quality like point to point wiring. Premium parts like an Alps Blue Velvet Volume control. Custom-wound output transformers for super-wide bandwidth and REAL bass that has punch and follow-through. Engineering like Adaptive AutoBias, Bad Tube Indicator, Super Quiet Relay source selection instead of cheap switches, and SmartWatts which assures you no headaches that for years have been associated with tubes. No longer will you be a slave to worry about how much time you left your amp on. Turn it up. Have fun. Use it every day. All day.
You can compare the sound and it will become immediately apparent. But if that's not possible, don't worry. The most well-known experts in audio have done it for you. While most products you read about get good reviews, they don't get chosen by the experts for their own personal use.
Bob Deutsch, an expert in audio and a well-known senior reviewer at Stereophile magazine, reviewed the ProLogue Premium in 2012. Not only did he give it a great review, he loved it so well he asked if he could continue to use it for writing reviews of top-name loudspeakers. For years now it's been mentioned in the pages of Stereophile, but in one 2015 review in particular, he really summed it up by saying:
“Ever since I reviewed PrimaLuna’s ProLogue Premium, for the June 2012 issue, it has been the model I turn to when I wanted a moderately priced integrated amplifier to try with a new speaker. It never disappointed me, and never seemed outclassed, even when the speaker was the Martin Logan Montis ($10,000/pair). At $2399, the ProLogue Premium to me represents the “sweet spot” for systems in the range of $4,000-$10,000 or higher.”
— Bob Deutsch, Stereophile Magazine
Did he say Martin Logan Montis? Those big electrostats? Yup. Just like in solid state, you can have a 100 watt receiver and it doesn’t sound as good as a high quality 50 watt amp. As an experienced audiophile, you probably already know that power has nothing to do with sound quality. Here is proof. Speaker reviews written by a qualified professional using a 36 watt amp. Welcome to the world of educated buyers.
ProLogue Class Power and Output 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. 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.
SuperQuiet Line Inputs
Input selector switches mounted on the front panel requires long wires to run from the switch in the front to the rear RCA jacks, and they invite stray noise like RF and EMI.
PrimaLuna has a better way. Instead of a switch, input selection is done using premium quality sealed relays mounted in the rear where you plug in your components. When an input is selected, that relay closes giving you the best connection possible. All the other relays are left open, so noise and signals from other sources can’t leak in. The signal path is now almost non-existent, so there are no wires to pick up noise.
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.
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.
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.
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, even the monstrous KT150. A future-proof design, PrimaLuna is compatible with NEW tube types not even thought of today!