nx2-Amplifier Update
July 25th Update. More testing underway over the last few days, including improvements to the compensation design and offset adjustment along a few layout bugs that have to be ironed out. June 23rd Update. Not much further progress as I’ve been assembling an X-Altra Mini II ‘BB’ for a friend. Once that is completed, I’ll […]
The ax-Amp: a 60W RMS class A Current Feedback Amplifier
Click this link to order 2 off ax- Amplifier PCB’s https://hifisonix.com/shop/2-off-ax-amplifier-module-pcb/ Part 2 of the ax-Amplifier was published in audioXpress, 15th April, covering the power supply, power control, mechanical assembly and wiring, followed by detailed measurements. Here is a short synopsis provided from the AX website:- Click on the link to visit audioXpress Part 1 […]
Ground Loops
Updated with new material 7th January 2019 This set of c. 70 slides is the culmination of my experience over a period of about 25 years building numerous power amplifiers and preamplifiers. I first started out in audio around 1975 or 76 as a teenager. Some of my creations were reasonably quiet – through pure […]
How to wire-up a Dual Mono Bloc Amplifier
A few people have asked about wiring up a dual mono amp aka dual mono bloc. In a dual mono bloc there are separate power supplies and lots of opportunity for cross channel ground loops and ordinary ‘classic’ ground loops as well. This wiring scheme addresses the situation were unbalanced connections between the source equipment […]
Amplifier History: The JBL SA-600
The beautifully styled JBL SA-600 amplifier was launched by the James B. Lansing company in 1966, and Bart Locanthi (the designer) wrote the technical article linked to at the bottom of this write-up in January 1967. I’ve included this in the hifisonix power amplifier library because it is one of the earliest – if not […]
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 between VFA’s and CFA’s, and even how to tell them apart. So, this document is […]