Lampucerized CD

One of the beautiful features of Lampucera DAC boards is that it is small and fits in small spaces.
Another good feature is that it just requires one 5 VDC by 50 mA  power supply
On this example I will show how a 40 Euro old Kenwood 4090 player gets its second life with high end pretensions.

A lampucera board, with full tuning will be implanted inside the CD player, using its SPDIF signal and parasitic power supply.
The DAC inside is like an Alien inside the belly of Sigourney Weaver.

kenwood 4090

This is well known player, we like it because of high reliability, pretty face, great ergonomics, great dot pixel text display, cool  drawer mechanism and low price. And for biiiig empty space inside.
Just what we need.

kenwood lampucera

First step is installation of new RCA sockets. The old ones are de soldered and removed.
New RCA's must be of course grounded.

lampucera CD

second step - lampucera (on the picture - stock unit without tweaking) is installed on metall hex bolt legs as close as possible to SP/DIF source.
The two holes on the side are for tube socket.


This is the Lampizator output stage power transformer with a three capacitor power supply for high voltage (150 VDC) and the heaters in this system can be AC powered. In Cathode follower triode there is no hum from AC heaters.
The transformer is mounted in the hole where originally the players foot was screwed. Now a 4 mm allen key bolt holds the transformer AND the foot on the other side.
A 820 uF cap and two 100 uF caps are hot melt glued to the transformer.
Resistors are 1 K to smooth the AC pulsation of the anode supply.
Each green cap supplies one anode of the triode - tube halves.

The tube of choice for cathode follower is 6N6P with circa 7 mA current.


This is a quick and dirty power regulated supply - a 7805 regulator without heatsink is soldered by its center leg to the groind which I found nearby (a PCB wire jumper)
The left leg of the regulator is supplied from a 12 V DC supply to the old opamps (opamps are removed now, remember? ) So the 12 V is unused and available.
Output - right leg of 7805 regulator is connected to electrolytic cap - 2200 uF by 16 V and then sent to Lampucera 5 VDC power input.
Lampucera cground is also connected to the GND with the regulator's center pin.

Simple innit?
Lampucera has now very pure, double regulated % V supply - just what the doctor ordered. The player is very happy and we don't need to buid the whole raw supply from scratch. This one costs 3 Eu.

lampizator lampucera

One tube is installed, triode mode, half tube per channel. Screen is grounded, heaters are 6,3 VAC supplied between legs 4 and 5.
150 VDC is supplied directly to legs 1 and 6 of the tube.
Each grid gets signal from lampucera DAC chip via two good caps. I used Tantalums - 47 uF by 6 VDC. Polarization plus towards dac.
Each grid has to see the ground via a 250K - 500 K resistor.
Each cathode has a 330 Ohm resistor to ground.


The cheap plastic sony lookalike transport now provides raw data to Lampucera which becomes a separate dac but sharing one box with the landlord Kenwood.

In this way the cheap and overall nice Ken became a giant crunching machine, with modern, detailed, full blooded sound, full of definition, space, depth and music.
For many people hearing this 150 Euro (raw cost) job would be a REAL SHOCK.

I also did the same in one Marantz 67, one MHZS66 and one other kenwood DPD 5090