This may be the Quietest Pre-preamplifer in the World!
Look at the deisgn in details:
- An indenpendent power supply
- There is no power switch
- There is a Trim pot whereby we can adjust the input capacitance to match with the output impedance of the Cartridge!
- Gold plated PCB which is still Bling bling shinning after so many years.
- Consideration of RF interference and to keep hi frequency response by trimming some of the resistance.
- The Expensive dual coupled FET pair X4 on the main board, that component was selling at about USD$20,00 a piece in 1983!
The power supply has a soldered cable of approx. 6 feet in length connecting to the amplifier.
There is no Power indicator nor even an LED pilot lamp, that is why John believes all these are not necessary as they may introduce noises!
I have changed the yellow REL-CAP x4 into Jensen Silver foil and silver leaded capaicitor 0.1 MFD600V. I spent HKD$5,700.00.
I found that the treble is more transparent and the bass is tighter as comparing with the original Rel-cap. Picture shown here is the original designed Circuit board hand made by John Curl.