Marantz CD-94 MK-2and MK1
Blonde or brunette? MK1 or MK2 ? what lies inside the legendary Marantz players?

here is the mk1 story

What can I say, after spending time with fantastic sounding players which go on ebay for 50 Euro, I was surprised to find out that this one goes for 1500-2000. Why?
There is nothing special about it. Electrically it is like Marantz 40, only with one extra DAC. The CD94 MK1 is really not any more special than any TDA player. The market "fame" is very powerful  tool indeed.
I am not saying it is a bad player - I love it. It is great. But it is not 10 or 20 x better than others.

So why did I buy one for myself ? Because the MK2 has balanced DAC and after lampization I can connect them to my beloved OTL amps via XLR and enjoy the music not only SILICONE FREE from DAC to Speaker COILS but also BALANCED from DAC to SPEAKER COILS. Not to mention that the whole system is RESISTORLESS - meaning that the CD, lampizator, amplifiers and the speakers do not have a single series resistor, not counting the amplifier's volume pot.

This is the famous PCB which makes the 94 being the MK2 - with DAC section, sitting on suspended legs above the output stage PCB. Not a very neat solution. Anyway, the tricky part is this: there is a small PCB which supports toslink digital output. On this PCB there is a chip which flips the digital signal in "mirror mode" - zeroes become ones and vice versa. This inverted digital datastream is then routed to one of the two DACS where mirror analog signal is produced.
This is the perfect example of balanced operation. For completely unknown reason marantz decided that we are too dumb to appreciate it, and mixed these two signals inside an op-amp. Producing only normal SE output via RCA. I can not believe how stupid it was. What did they have to loose - the cost of two XLR sockets? (Of course SE outs could have been kept paralelly to XLR).

But now we clever DIYers can reach back to the DAC chip legs and resurrect the balanced signal, making this a trully balanced player - from DAC to output, and all tubed at the same time.

Wonderful CDM1 with a drawer built like a dream. People say, that after years (20 years old !!!) the v-belts either break or slip and the mechanism fails. I say - change these belts (4 of them) and it will run for another 20 years! It took me an hour to change all belts and the mechanism is a wonder to operate.

General view.
The lampizator transformer will go to the upper left corner.

I decided to use octal tubes with black glass - the Kenrad / RCA black glass 6SN7GR  from JAN NOS.
This is an attempt on the overkill...

The CDM1 is really well made - it is sort of equivalent of Mercedes Diesel engine from the seventies.

Look at these monstrous Elna caps in main PS board. The twin towers !

The main PCB with output op-amps removed. Blackgates awaiting to be saved and rescued.
In the upper right corner you see the small vertical PCB which flips the digital phase for one DAC. Not a very neat solution but anyway - thats how Marantz operated.

This is the digital board standing on the side.

Oh  this drilling was a nightmare.

Sockets are already in place.

Octal sockets inside 27 mm holes. So far so good.

Because the power supply wires had to be quite long, I decided to add a smal lytic cap near the anode. So small impulses of current can be realized immediately. without drawing current from main cap, 40 cm away from the tube. These are 22uF/200V caps between legs 1 and 9.

In such tight space fitting 4 tubes is a real challenge.

These 6sn7GT tubes are 100% elecrical equivalents of the 6H1P from Russia, the 6H8C, 6N9P from China, and you can try thousends of variants from around the world, including the famous red-bases.

Transformer of lampizator sits in the space of the corner - the AC input PCB with RFI filters used to be here, now it will sit atop the toroid.

LISTENING: Without hesitation, the balanced output of this CD is the best I heard to date (october 2007) and I was completely satisfied by feeling of doing justice to the legend status of this unique player. Since I prefer XLR connection - this player is now my KING OF ALL CD's. But for those who use RCA single ended connections - the 94MK1 is a better choice (and cheaper too). The Grundig 9009 is still better as a SE source by a very small margin. But my amplifiers come to life only in XLR mode.