Evo 200 Preamplifier
JAPANESE ALPS BLUE VELVET POTENTIOMETER
The best tube preamps use analogue volume controls. Not volume control chips. Look inside the most well-known brand of tube preamps and you will see a chip called a DS1666-10 Digital Resistor IC. At Primaluna, we understand the temptation to use this chip as they cost $4 each (half that in quantity!). The preamp will sound fine and be quiet, but true to “chips” it will add an electronic “sheen” to the sound. PrimaLuna prefers analogue. And we use the Gold Standard in motorized potentiometers: The iconic Alps Blue Velvet. Why? Because they track perfectly, stay quiet, and don’t sound like chips!
In the world of preamps, experts agree that tube rectification is the gold standard. It’s quieter than solid state rectification, dropping the noise floor. And it offers the most natural, textured, and vibrant presentation because the circuit is now pure tube. But because it is expensive to implement, you’ll only find it in the top of the line models typically costing $10,000 or more. Finding a preamp using one rectifier tube is sweet. PrimaLuna goes even further using two 5AR4 rectifier tubes in a dual-mono design to present your music with a three-dimensionality that will give you goosebumps.
Expensive and exotic preamps always use a dual-mono design to achieve a level of imaging not possible otherwise. Most manufacturers don’t employ dual-mono because of expense. It requires two power transformers, double regulation circuits, and in fact….everything is double. In effect, dual-mono means building two discrete and separate preamps into one box. It is so expensive to build, it’s a rarity even at the highest price points. All PrimaLuna preamps are dual-mono for the ultimate in stereo imaging and a sense of space that goes on forever.
DUAL TOROIDAL POWER TRANSFORMERS
Power transformers generate two types of noise, magnetic and acoustic. That's why toroidal power transformers are used in the very best audio products. Compared to standard transformers, toroids radiate about 1/10 the magnetic field that pollutes music and obscures detail. Additionally, the absence of an air gap typically means toroids have an 8:1 reduction of acoustic noise. As transformers are the most expensive components in any audio product, manufacturers will even house cheaper C-core and EI-core transformers in an outboard power supply box with an umbilical cable rather than upgrade to an expensive toroid. The increased cost is significant, but PrimaLuna doesn’t cut corners. All PrimaLuna products use massive, potted toroidal transformers. PrimaLuna transformers are enclosed in a metal housing and then potted in a non-microphonic resin to further reduce noise and to protect the windings from moisture and deterioration forever. They are massive, resulting in a preamp weighing a substantial 39.6 pounds.
SUPER QUIET LINE INPUTS
Input selector switches leak noise and signals from other sources, as they never turn off the other inputs completely. And, they deteriorate with age, requiring the use of cleaners. Many are mounted on the front panel requiring long runs of wires to the back panel inputs. These wires pick up stray noise from 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.
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.
Custom Wide Bandwidth Output TransformersOutput transformers are the most important part of any tube amp. They determine how low the bass will reach and how high the top end goes. 250 watts of power will have no top and bottom extension if the output transformers don't have the bandwidth. We use lower power to extend tube life, and bandwidth to give you slam. Transformers are the most expensive components in an amplifier, so manufacturers save money by using ‘off the shelf’ units available on the market. PrimaLuna output transformers are custom-designed, wound in-house, and massive. One reason why no other brand sounds like a PrimaLuna. "The flat tops and bottoms of these squarewaves correlate with the amplifier's extended low-frequency response; PrimaLuna's output transformers are of excellent quality." -John Atkinson, Stereophile Magazine
The best way to add power and keep running cool is an bigger build. We increased the size of the power transformer, added all the supporting circuitry including tube sockets, Swiss silver-plated OFC wiring, Takman resistors, SCR Tinfoil caps and a second Adaptive AutoBias board. And of course, four more EL34's for unrelenting power. And if you want the ultimate, add a second HP later and flip the switches to mono. Incredible!