HPA-1 Class A Headphone Amplifier
This class A headphone amplifier from 2014 is based on the design I used in my ‘Symphony’ preamp. It will drive a pair of 32 Ohm headphones to 6V pk-pk and remain in class A with < 330 parts per…
kx-amplifier: A very high performance 28 Watt class A Current Feedback Amplifier
The Hifisonix kx-Amplifier is a 28 Watt class A DIY Current Feedback (CFA) power amplifier featuring low distortion, wide bandwidth and fast rise/fall times. It can be operated either in pure class A mode, or in class AAB mode with…
JLH 10 Watt Class A Amplifier
This is a copy of the original John Linsley-Hood article that appeared in Wireless World in 1969. This design, almost 50 years old, is still built in its hundreds all over the world. A quick root around on the web…
Class A Buffering the Correct Way
Here’s a simple way to force an opamp output stage to run in class A when used with a discrete buffer output stage – it takes just 1 resistor to provide a near constant current source load. Operating the opamp…
Ovation nx-Amplifier: A High Performance 100 W class AB Current Feedback Amplifier
This power amp design is based on the sx-Amplifier topology, but with the TIS and output stage re-configured for class AB operation, enabling it to deliver 100 W into 8 Ohms. I have kept the design very simple, retaining the…
