
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…

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…

Ovation sx-Amplifier: A 15 W Class A Current Feedback Amplifier
Update January 2018: For the sx-Amplifier, you can now buy a complete set of very high quality Double Sided THP Gold Flashed PCB’s from Jim’s Audio here: sx-Amplifier DSTHP Gold Flashed PCB Set If you are having problems wiring up…

CFA vs. VFA: A Short Primer For the Uninitiated
This article was written in 2014 in response to what can only be described as a vitriolic debate as to what constituted a CFA on diyAudio.com. At the time, many of the participants were struggling to grasp the fundamental differences…
CFA Diamond Buffer IPS: Does it Operate in Class B or class A?
There is a persistent assertion by small group of amplifier design practitioners that the diamond buffer input stage of CFA audio amplifier operates in class B (or AB) mode wherein there is a hard ‘handover’ between each half of the…