I am about to embark on a Krell KSA-200S Class-A Amplifier Repair and Restoration, in this case for a very good friend of mine.
As many of you will know, the Krell KSA-200S is a beast of an amplifier, up there with the very best products Krell ever made. It is almost unliftable by one person, being hewn from solid slabs of steel and aluminium.… Read more
I decided to build a resistance standard, for use with my test and measurement gear and good enough that I could some calibration on test and measurement equipment owned by other people. I wanted to build something that would not be prohibitively expensive and that would allow me to reliably calibrate the resistance ranges of my two Keithley bench multimeters and various Fluke hand-held DMMs to at least 0.01% accuracy.… Read more
I’ve purchased some great new vinyl of late and recently took delivery of some great new polypropylene record sleeves. I get asked lots of questions about how I sleeve and house my records, so I figured I’d write an article about re-sleeving your record collection!
There are two main types of record outer sleeve: polyethylene and polypropylene.… Read more
I recently finished another round of modifications to my Musical Fidelity Tri-Vista 21 Class A Tube DAC. In this post, I go into details about the changes and the MIL-spec vintage parts I’ve used!
Actually, I will do some more power supply modifications in 2018, more on that when it happens. This is part three, in an ongoing process to develop and evaluate the best performance mods for the wonderful Musical Fidelity Tri-Vista 21 DAC.… Read more
I recently built a dual-mono LM3886 chip-amp / gainclone amplifier from a kit sold by Brian Bell, at chipamp.com. In this article, I discuss the history of the gainclone and how I built my first chip-amp!
The LM3886 is one of National Semiconductor’s single-chip monolithic amplifier integrated circuits. It’s almost an entire amplifier-on-a-chip, with only a few extra parts required to build a fully functional, high-performance amplifier.… Read more
After successfully building my LM3886-based gainclone project amplifier, I’ve decided to build a version that is better suited to driving low impedance loads.
This lead me to the LM4780 chip from TI, which is just two LM3886 dies in the one package. It can be used as a stereo amp, or a bridged or paralleled mono amplifier.… Read more