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. More important, it is the ONLY circuit of its kind that is truly "adaptive" by addressing "tube pinch off" at higher volumes, therefore reducing distortion by over 50% and greatly extending tube life. 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. It even has a fine-tuning switch for EL-34 and KT88/KT120/KT150 tube types.
POINT TO POINT WIRING W/ SWISS MADE WIRE
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.
EVO 300 and EVO 400 models use Swiss-made, silver-plated, oxygen-free continuous crystal (OCC) copper with a Teflon dielectric in the critical signal path for superior signal speed and increased clarity.
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. We proudly tell you our 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 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. 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.
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.
OUR 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 our 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, our 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!