Q-tron Audio PA34B 80W OTL Mono Power Amplifier

The A34B is a monoblock amplifier with an output power of 80 W. The circuit design is based on the PA12, but modified to drive four output tubes; with twice the current drive capability of the PA12, the PA34 is capable of driving less efficient speakers.

Q-tron's OTL (Output Transformer Less) amplifiers provide a clearer, more expansive sound quality than other tube amplifiers. By eliminating the output transformer required by normal tube amplifiers, the distortion and frequency response limitations caused by the transformer are avoided, resulting in improved sound clarity and response. In particular, the output stage is configured in a push-pull arrangement, and the Futterman circuit, uniquely designed to achieve low impedance without the use of a transformer, provides low output impedance and excellent balance. It also features active noise canceling technology to keep noise below 100 dBA and a design that achieves very low distortion without excessive feedback. In addition, the minimal use of vacuum tubes has proven to be highly reliable and long-lasting. All parts are designed and manufactured in Sweden, and the use of high-quality components ensures high performance over the long term.

The amplifiers are largely built on large PCBs, but point-to-point (PtP) technology is used for critical components. In addition, ceramic solder supports capable of withstanding 5kV are used, and chassisThe chassis is made of 10 mm thick aluminum, providing excellent mechanical stability and completely eliminating noise caused by vibration.