Auralic Preamplifier - June 2024 Service / Modification

This preamplifier was sent in by a good friend of mine Colin in the UK. He had been having some issues in his system that almost sounded like there may have been a failing transistor or op amp. Either way it needed shipped to the US for diagnostic and repair, and Auralic quoted him triple my hourly labor charge, so he sent it to me first. 

Luckily there weren't any failing amplification stages, and I say that as it is very obvious that they do not want unauthorized repairs. The output section is actually fully encased in separate modular units. I didn't notice any distorted output, but there was a presence of noise that was easily found after a full disassembly of the preamp. The input side of the preamp is located in the right side, and the output on the right. The power supply sits dead center of the component and the input is connected to the output via a very small gauge cable with plug in connectors, with the volume pot in the center. This cable also tied the two signal ground planes together and utilized this ground connector also as a shield that was very poorly connected. On top of this, this signal wire was glued to the bottom of the PCB with some attempt to keep it over a flood ground plane, but still crossed directly underneath the power supply. 

I replaced this skimpy wire that fell to pieces on removal with a quality star quad microphone cable and directly soldered this signal path, removing the multiple connections between input, output, and the volume attenuator. All in all I removed 6 excess points of contact ensuring the most direct path for the signal, and rerouted the signal wire away from the power supply.