In this second article on the Marantz SC-80 and SM-80, we look at the SM-80 power amplifier and a tricky repair and restoration. The Marantz SM-80 stereo power amplifier is a reasonably powerful, well-made, mid-range consumer amplifier from around 1990. It typically sold with its companion, the Marantz SC-80 preamplifier and I have just finished […]
In this article, I discuss the history of the LM3886/chip-amp/gaincard and run through building my own dual-mono LM3886 gainclone amplifier. The LM3886 is one of Texas Instrument’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. The LM3886 features low
I recently restored this gorgeous Luxman M-4000A power amplifier and matching C-5000A preamplifier. Let’s start with the beautiful M-4000A. Apparently, the legendary Tim De Paravicini designed the original M-4000. The improved and even rarer Luxman M-4000A probably also came from De Paravicini’s hand, but nobody seems to know for sure. UPDATE: Check out my recent
I recently modified a Musical Fidelity X-CAN V3 headphone amplifier. My goal was to see what sort of improvements I could make without spending too much cash. The Musical Fidelity X-CAN V3 uses bipolar output devices, with a tube driver stage. The tube driver stage is a JAN (Joint Army/Navy) 6922 mil-spec dual-triode tube, per
Musical Fidelity X-CAN V3 Headphone Amplifier Upgrades Read More »
After successfully building my LM3886-based gainclone project amplifier, I’ve decided to build a version better suited to driving low-impedance loads. This leads me to the LM4780 chip from TI, which is just two LM3886 dies in one package. It can be used as a stereo amp, or a bridged or paralleled mono amplifier. The datasheet
One of my recent jobs was inspecting and servicing a lovely example of a Krell KSA-150 Class A Power Amplifier. You may have already watched my restoration video, where I completely refurbish one of these beasts. This video has actually generated a great deal of interest and I receive lots of queries in relation to
This video documents my comprehensive overhaul and restoration of a gorgeous Krell KSA-150 class-A power amplifier. This wonderful KSA-150 developed a serious fault at some point in the past. This had been quickly fixed and was sold to me in very poorly repaired condition. Because of this, I decided to completely overhaul the amplifier and
