Quad hifi revision

As design engineer, I like to figure out how things work and I have a soft sport for eye-catching design. This Quad hifi installation was at the top of its game back in the day it was made. Nowadays they’re popular second-hand.

After years of use, the sound of my unit wasn’t quite as high end as it used to be. It didn’t sound right, was a bit noisy and sounded like a distant thunderstorm when switching off. So I decided to revise the model 33 pre-amp and model 405-2 power amplifier. Luckily, both units were from a time when electronic components were sizeable and simple. So, no small SMD components or chips, making soldering a lot easier.

The 33 was disassembled completely and all capacitors and part of the resistors were replaced. At the same time, I corrected the input levels of CD-player, pickup and radio to just about the same level, to ease switching between channels and prevent loud mistakes.

The 405-2 was serviced with new connectors, internal wiring and  power supply capacitors.

With a matching pickup, a piece of seventies hifi is revived!

The next project is already waiting: a run down Beocenter 1900-2, found at a second-hand store.