I came across this old Marantz CD4000 with such a irresistably low price tag, and bought it just for fun. Then I remembered that the extinct Dutch-made AhTjoeb4000 CD Player was build using the same base.

The idea of tubing was then born. However I wish to use octals instead of the standard 9pins as by AhTjoeb. My understanding was that the bigger the tube plates surface, the better sounding it will be.

This poses a challenge of much higher heat dissipation within the confined chassis. Rather than ruining the top plate by perforating it, I installed a small computer fan at the bottom plate to suck out the heat, adequately reducing the RPM so as to eliminate the fan-rotation noise.

The tube topology is a SRPP on a balanced power supply where the B+ and the B- will each cancel any existing hum. A additional transformer was custom wound to supply the tubes HV and the heaters requirement.

NOS paper in oil as coupling and output caps. Cardas binding posts. Internal wiring uses CAT6 single strands. Due to tight space within the CD player chassis, I devised a self designed and made PCB to accommodate the tube topology and the rectification array.

Unfortunately there was no space left in the chassis for 600:600 Ohm output transformers, I had to use only PIO 1uF output capacitors.
The project was completed end year 2010 and burned in thoroughly over year 2011.

Comments

• Orronoco
• 13 January 2015 at 07:47PM
• I cannot believe this CD player actually consist of small board in the bulk case.
  
  But you make this CD player very nice looking, great job. Cheers!