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 31 pounds.
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.