Fi 2A3

About the Fi 2A3

The Don Garber Fi 2A3 is a minimalist direct-coupled, single-ended triode amplifier using a 6SF5 driver and 2A3 directly heated triode output stage. Its signal path omits interstage coupling capacitors and uses a MagneQuest DS025 output transformer with point-to-point wiring. The amplifier produces approximately 3 watts per channel and is intended for use with efficient loudspeakers. Tube-rectifier versions are documented, although the specific rectifier may vary by production version; therefore, the 5Y3 designation should not be treated as universal. The Fi 2A3 reflects Garber’s emphasis on a very short signal path, simple circuitry, and natural musical presentation.