ART27A

Speaker systems vary in sensitivity with some highly regarded speakers measuring an output of 86 dB or less from one Watt at one meter to other high-efficiency systems producing as much as 104 dB. Further, room dimensions, speaker placement, and listening placement vary widely – also significantly impacting power demands. Accordingly, the power demands of different high-end audio installations vary widely. To address a range of these needs, we offer these two amplifiers utilizing the same basic circuits and built to identical standards, differing only in the number of output tubes, size of the output and power supply transformers, and scale of the power supply required to achieve their different output power levels.

The circuit for these amplifiers is designed for Class A operation of KT88 output tubes configured as triode devices – a single pair for each channel achieves 36 Watts per channel in the stereo ART27A suitable for highly efficient systems, while the mono ART108A employs four pair to produce 160 Watts – ample power for the vast majority of applications.

The amplifiers boast independent discrete regulated power supplies for the output stage in addition to separate regulated supplies for both input and inverter stages (with separate regulators for each channel in the ART27A).