"The Fi 2A3 is the result of a search for the purest, simplest and most elegant single-ended amplifier. It's direct-coupled, which is to say there are no coupling capacitors. The signal path consists of a 6SF5 single triode driver (nothing paralleled), a 2A3 directly heated triode, a MagneQuest DS025 output transformer and a few inches of ...

Here we have perhaps the most well known of Don’s amps, the 2A3 / 45 monoblocks. These amps run the 2A3 tube with a 5V4 rectifier, but changing that to a 5Y3 (or an 80 on adapter) brings the voltage down and allows the amp the run the 45. This same basic design was also used in Don’s X amps, one of which it was my pleasure to own a few years ago.

“The fi 2A3 amplifier is the simplest and most direct amplifier available today. It consists of a single triode voltage amplifier direct coupled to the 2A3 output stage, one of the best output transformers around, all connected with a few inches of silver wire.

To afficionados of single-ended triode (SET) power amplifiers, the 2A3, directly-heated triode is the stuff of legends. Many believe it has the best balance: a superior melding of audio charm and power compared to other power triodes.

2024年9月3日 · Fi 2a3 Stereo Amplifier. In perfect working order. New Sofia Electric 2a3 tubes. Plus other NOS tubes included. Original shipping box and correspondence from Don Garber. Some upgrades original to amp as included and described by Don. I am the original and only owner. A landmark in audio design, construction and sound.

The Fi X 2A3 doesn't exactly hang around in mass quantities. Turns out the X is Don's entry level bonanza, costing a paltry $995 in stock (Hammond 125E transformer) form, though you can specify an upgraded transformer from Magnequest which brings the price up to just under $1400.

2022年7月17日 · So, I started with a typical operating voltage for the 2A3 (250Vak), using a B+ of 295V. There's supposed to be 45V across R5, which is the grid leak resistor for the 2A3 and plate load resistor for the 6SF5. This results in some pretty unorthodox operating points, with about 15Vak/0.5mA across the 6SF5 and the 2A3 operating at just 5mA.

2012年1月7日 · The Fi 2A3—first produced as a stereo amp, then as a monoblock—is elegantly simple: a single-ended-triode (SET) amplifier with a completely tube-rectified power supply, in which all tubes are heated by AC, straight off a secondary winding of the mains transformer.

The Fi 2A3 amplifier is the simplest and most direct amplifier available today. It consists of a single triode voltage amplifier direct coupled to the 2A3 output stage, one of the best output transformers around, all connected with a few inches of pure silver wire.

2024年9月24日 · The new old stock 2A3 tubes from Emission labs have spec sheets and they are an extra, $600 for the pair, plus $25 shipping for the tubes if you want them.. The amp will ship to lower 48 and for about $150 with insurance, UPS ground.