OTOMON LAB 71A drive 45/2A3/300B compatible tube amplifier monoblock 9.5W power Zero NFB (O.U.D.D.C). The output power is 9.5W with 300B tube. 6W with 2A3 tube and 2.5W for 45 tube. With Zero NFB, the response frequency is flatted from 30Hz to 25Khz, this is impossible to all amplifier that I made before.
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