This is a Nakamichi PA-304S tuning & full overhaul amplifier. I was using it until the other day, so there are no problems with its operation.


The primary power supply has been replaced with two low ESR capacitors made by Rubicon, and the secondary power supply has been replaced with a low ESR made by Nichicon. Other power supply capacitors have been replaced with Nichicon low ESR capacitors and Toshin Kogyo low ESR capacitors. In addition, to prevent heat generation, the resistor in the power supply section has been replaced with a metal oxide film resistor.

Regarding the amplifier part, we have socketed the operational amplifier and replaced it with two operational amplifiers (MUSE01). The power supply part of the operational amplifier may also be burnt, so we have strengthened it as a countermeasure. Other coupling capacitors have also been replaced with film capacitors and Nichicon KZ capacitors.

The resistance in the audio input/output section has been replaced from a carbon resistor to a metal film resistor, and the film capacitor has also been replaced with a German-made film capacitor. Small capacity capacitors have been replaced with styrene capacitors.

The image is also attached, so please check it before considering purchasing. I think Nakamichi's already wonderful PA-304S will be further upgraded and you will be able to enjoy great sound for a long time. Please understand that there are individual differences in how people listen to sound.