Ikke det at jeg er noe særlig bevandret med elektronikk, men mosfet utganger i en pre er uvanlig. Mosfets er jo kjent for å ha en litt rundere lyd enn vanlige transistorer. Dette gjelder antakelig denne også? Nedsiden er at de ikke gir like mye strøm, men det er vel neppe et problem i en pre. ;D
Hele konstruksjonen virker å være spesiell. Den skal kunne gi 10w ut !!!! Står litt mer i brosjyren her for den det måtte interessere.
https://www.canadianhifi.com/sites/...nuals/Belles LA 01 Stereo Preamp Brochure.pdf
Klipp fra en annen test:
The power supply is housed in a separate box and isolated from both the preamp and the AC power source. Connecting the two boxes with a specially designed power cable keeps the noisy power supply from affecting the signal. Four stages of decoupling from the outside AC power line are intended to give the LA-01 a level of performance approaching that of battery-powered preamps.
The LA-01 has four single-ended inputs and two single-ended outputs. The lack of balanced inputs and outputs made me question whether the LA-01 was the ideal companion to the MB-01 monoblock, which has a balanced-input option. Dave Belles said that he has developed and seen the value of balanced designs in situations where many circuits are connected (for instance, when he was involved in wiring the literally thousands of communications circuits at the Cape Kennedy control center in the 1960s), and also when power amps are bridged. But he sees little advantage to balanced circuits in home audio as long as other key elements, such as the ground, are designed well and there’s enough output power. "You just end up paying for extra things you don’t need," he told me.
Bruce Jacobs raised the potential advantage of a balanced design in driving long or high-impedance cables, or an amp with high input impedance. "But this isn’t a problem for the LA-01," he said. "The preamp is producing 10W of class-A, which, even unbalanced, can drive any amplifier and accommodate any cable." Belles himself was straightforward about the benefits of his preamp, which uses power MOSFETs in the output stage: "The LA-01 can give any power amp a good swift kick in the ass."
Beyond power, the LA-01 is designed to provide high-quality amplification without coloring the sound. Belles’s goal is that it produce detailed sound with clarity and openness, and he expects it to be able to compete on quality and performance with any preamp on the market.