pioneer pd-71 schematics wanted

[federico moreno]

I have an old Pioneer Elite Cd player whose laser is dead. The audio pcb is fitted with 2 Burr Brown PCM-58 18 bits da converters -long ago obsolete, but very good sounding and with specs very similar to PCM-53-.
I want to make a standalone non oversampling dac using that PCB, but I have no info about the topology of the circuit.
Have any of you, nice persons, some schematics of that old horse?
Thank you very much in advance...

[guido]

PCM58 is 18 bit 'version' of PCM56. Interface is equal (except for 2 more bits ) Search here and on the net, think there is enough on the 56.

Next question is to find the dig filter and the decoder. You need to find out how to bypass the filter and connect the decoder to the dacs.

This probably requires logic, since the dac's are mono:
the serial interface holds only one channel. The connection filter-decoder is probably left/right combined.

What more chips are inside?

[federico moreno]

Sorry for the delay, Guido.

Inside the PD-71 I have found the following IC´s:

NPC5803ap -as far as I know, this is a eightfold dig. filter-

sony cxa 1082b
sony cxa 1081 -I think that the pair is for servo purposes-

pioneer6301ycp -maybe display and controls-

sony cxd1135 (? )

sanyo lc3517. a dual opa next to the PCM58

I suppose, based on my readings of other recently founded threads, that I´m in need of a spdif receiver, maybe cs8412 o cs8414. I have ordered samples of the 8414, but recently Argentina was deleted of the samples program of Burr Brown -a sad affair, because BB products show an amazing level of excellence-, and maybe CirrusLogic -manufacturers of cs8414- will adhere to that politic too, because I have not received any answer yet.
You know, Argentina is some sort of finisterre, and there isn´t a lot of demand of good electronics audio parts here. My country is not an ¨economically viable¨ entity as far as ¨the powers that be¨are concerned.

As a matter of fact, Burr Brown free samples program looked too good to be true: free chips in a couple of days delivered to your door... Not the sort of thing that we argentinians are used to.
Here, everything strange -like good diy audio, for example' - is straight out of the blue, nerdish or futile .
A sad reality for diyers in this beautiful and difficult country.

You can´t imagine the price asked here for a mere opa604: 15 us dollars each! the price of a opa627! And you have to wait weeks for the local dealers to stock the ítem...
but i'm a little out of topic...

Well, I'll wait for those cirrus samples meanwhile and I´ll let you know. I´m not very experienced with digital audio, but I´ll try to do my best.
Thank you very much.

[guido]

Hi,

I dont know much about the sony chips and the npc dig filter.
One of the sony's is the decoder which feeds the dig filter.
This then feeds the dacs.

You need to look at the 8412 output and convert it into the signals the dacs use. So get the datasheets and design glue logic.

I think it can be easier to leave the npc in and connect the 8412 to it. Might be without any glue logic (?), again a matter of reading the datasheets. This time the npc one. This might also tell you what the dacs need if you cannot find info on them.


Regards,

[guido]

How to implement dual PCM56 from CS8412

think of pcm58 as 18bit version of pcm56. The 8412 only gives 16 bit data, so you loose the 18bit accuracy of the dac. Dunno if it is as easy with the 58 as with the 56 in the above post. It's all in the datasheets.