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<\/p>\nThe F2 is a stereo power amplifier which offer 5 watts output. Like the F1, it is a current source, but it is different in several ways. The F1 operates in what I would call \u201cbalanced single-ended Class A\u201d and the F2 operates as simple single-ended Class A. The output impedance of the F1 is 80 ohms, but I have provided the F2 with an output impedance of 15 ohms, based on the observation that no useful application of the F1 called for a higher figure. As a single-stage single-ended circuit the F2 has no use for balanced input connectors so it simply has RCA inputs, as seen here in this simplified schematic:<\/p>\n
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While the F1 has a crisp sounding 3rd harmonic signature, the F2 has a richer pure 2nd harmonic character, and this difference is the primary justification for offering a second no-feedback current source amplifier.<\/p>\n
Another remarkable thing about the F2 is the very wide bandwidth \u2013 it is down about 0.5 dB at 200 Khz.<\/p>\n
Will it replace your favorite 300B SET? Maybe, maybe not. In any case the only copies are available used. For a short time there are a very few F1J units available which use new power Jfets instead of the Mosfets \u2013 see the F2J product page.<\/p>\n","protected":false},"excerpt":{"rendered":"