The input impedance of a.c.-coupled op amp circuits depends almost entirely on the resistance that sets the d.c. operating point. If CMOS op amps are used, the input is high, in current op amps up to ...

This HiFi headphone amplifier circuit design is normally used to drive a headphone with a relative low impedance. It provides one watt power output and it can also be applied as an output stage for ...

Audiolab has unveiled the sequel to its five-star 6000A stereo amplifier. The new unit – logically dubbed the Audiolab 6000A MkII – promises to take the original's performance to new heights, and ...