Mastersound PH1 Phono Preamp
This is one of those products that looks very attractive, and sounds pleasing. But something is missing.
Mastersound put a lot of thought into the design, but seemed to be on a tight budget. Parts quality is mediocre with mismatched parts and a weak power supply.
First we started with the power supply.
A custom toroidal transformer was installed.
The undersized rectifiers were then replaced on both filament and high voltage.
All filter capacitors were changed from the cheap no-name brand to Panasonic (other brands may be used). Filter capacitance was increased 80% on the high voltage and 50% on the filament in the process.
We also noticed carbon composition resistors in several key locations. These noise makers were changed out for quality metal film types.
The last change is to install new coupling capacitors.
Total cost $550.00