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
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.
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
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