Considerable effort was taken to design a preamp that is as clean as possible to satisfy discerning audiophiles, while maintaining the best performance even- and specially if connected to solid state power amplifier. Combining the most advanced, triode/junction FET hybrid topology and solid-state regulation - without any feedback - the Asty Line is a remarkable performer. This also reduces the output impedance to about 100 ohms - capable of driving any power amplifier, tube or solid-state. It is the answer to the impassioned quest by music lovers for a high performance, reliable and affordable tube preamp. While conventional tube preamps have always been recognized as the ultimate, and expensive, way of listening to music there have been serious impediments to wider scale use. The rumors you heard about conventional tube circuitry are true, tube preamp are expensive, tubes can get noisy and you cant get much gain from a tube circuit. The Asty Line hybrid tube/FET circuit eliminate all of these conventional problems and gives you the sound quality of tube and the reliability of solid state. The only way to bring the sound quality of tubes to the masses is by eliminating the tube tremors. By integrating FETs with tube we eliminate all the weakness of tubes and preserve their unique ability to reproduce real music. The preamp circuitry uses FETs in those sections that are stressed and usually create noise, in addition, the FETs eliminate all tube microphonics. In the Asty Line all of the audio information appearing at the input including imaging, dynamics, purity, and musicality are preserved completely and delivered to the output without any distortion or alteration. One of the design factors that is responsible for the Asty Line.
The LS17 SE preamplifier benefits from a long tradition of exceptional preamplifier technology from Audio Research and shares many common traits with its larger peers.
The REF5 is only the second Reference preamplifier to have its main board laid out horizontally, after the REF Phono2, with its transformers off the board and mounted on the sides of the chassis. The new audio circuit is fully balanced, pure Class-A triode, with zero feedback. The tube complement includes four 6H30s in the analog stage, with a 6550 and a 6H30 in the power supply. Massive energy storage, the most of any Reference preamplifier, provides tremendous dynamic capability. Total gain is 12dB via the balanced outputs and 6dB via the single-ended outputs.