So, almost one month work in my sparetime:
My Nakamichi OMS-5EII updated with the Placid/Buffalo/Ivy combo.
A future-proof marriage, even though the Nak is 20 years old, I still have spares:
Lasers, belts, gear. Bought them 15 years ago, when Nakamichi declined.
Never needed one spare till now, except a belt.
With the Buffalo, the Nak made a giant leap: being one of the best players at its time (around 1986),
it now sounds like a crappy mp3 compared to the Buffalo.
The tricky part of the mod:
The Placid/Buffalo/Ivy combo + toroids would have easily fit where the original PCM-54KP based DA-board was.
But there, deep in the machine, the placids would not have been well vented.
But venting holes are only at the back of the Nak.

So for better ventilation the placids had to be attached to the backpanel, with
1mm room left for the Placid bipolars pcb not to touch the cover or bottom plate of the Nak.
That is why the the connectors for the powerlines are not there any more, there was no room
for the cables coming from the sides. So they had to be soldered, coming from the back or front.

So this had to be precise - with only a handrill, well, at hand.
Also the aluminium subcase, where the original DA-Board was located, hat to be sewn open for the Placids.
It originally reached to the backpanel.

For all cabling I used XLR-cable, so even the DC-powerlines are shielded, but the shields are not connected to Placid/Buffalo/Ivy combo.
The cables´shields are connected to the players case, on both ends.

The stacked Buffalo and IVY are even in an aluminium box inside the player, because who knows, what 25 year old digital circuitry emits. But for fitting them into the box, the height had to be reduced with some tricks:
Shorter standoffs and shorter connections between the boards.
The Nak and Placids run with two custom wound transformers, the transformers have several secondaries. Surprisingly cheap, only about 50$ each.
You can have them made her in Germany by a company named Badel in Munich.

So the electronics are completely seperated and are powered seperately, by two power switches on the back.
The Nak communicates with the Buffalo via SPDIF.
The SPDIF output for the Nak had to be constructed as well by the original Decoder (Sony CX23035) communicating too a DIT4096 SPDIF Transmitter.
Originally there was no Digital Out on the Nak, later decoders had a SPDIF output already implemented

So the Nak also serves as a D/A converter now, it has 5 SPDIF inputs, one of them optical
(but with a cinch-jack, I cannot drill square holes)
How inputs are selected? The the former power button on the front has become the input selector.
One push, source two, next push source three etc.
When being powered up, the input selector resets to source 1, the Nak itself.
The (black) board for it (and some extra power supplies) is behind the tray assembly,
The toroids are beneath it.

I only have a video camera for making pictures, so quality is not good...
And, as I now see, the images are very big, 1920 x 1080, you´ll have to zoom back in your browser.
BTW, the Nak´s top cover is made of black opaque glass, of course shielded with copper....

Edited by user Friday, October 22, 2010 9:33:44 AM(UTC)  | Reason: Not specified