Q-tron Audio PA3B 2x8W push-pull tube OTL power amplifier

The A3B is a vacuum tube OTL amplifier that achieves 10 times lower distortion than other OTL (Output Transformer Less) amplifiers through a unique driver circuit. With two 6C41C tubes on each channel, the unique driver stage achieves an output power of 8 W. Distortion at 0.5 W is as low as 0.01%, and active noise reduction keeps hum and noise to a very low level.

The PA3B employs the Futterman circuit, a circuit design that eliminates the need for an output transformer, resulting in excellent frequency response and outstanding low distortion. The Futterman circuit is known for its ability to maximize sound transparency and realism, especially in OTL (output transformerless) amplifiers.

The PA3B is a lower output version of the PA12, which was reviewed by Dick Olsher in "Enjoy The Music" and described as "The Q-tron PA-12 is unmatched. He also praised it as "a tube amplifier that redefines the possibilities of push-pull design. The PA12's excellent sound quality and transparency can be fully enjoyed with the PA3B.

The PA3B design uses large PCB boards, except for critical parts that have a significant impact on sound quality, and critical parts are assembled using point-to-point (PtP) technology. The structure is constructed to withstand up to 5 kV using ceramic solder supports. The chassis is made of 10 mm thick aluminum, providing exceptional mechanical stability and completely eliminating noise caused by vibration.

The PA3B takes the rich expressiveness of a tube amplifier and the transparency of an OTL amplifier to the extreme. Its clear sound delivers new excitement to true music lovers.