old sansui cd player mods

[sss]

hello guys
i got an old cd player from sansui ,model cd 200.
its working well over 8 years allready so now i'm trying to mod it .
i'm thinking of using a new dac for it but i dont know if all new exotic dacs will be compatible
the dac inside the cd player is kda0316 from sansui
according to the datasheet the dac is for cd players that uses a dynamic level shift conversion method , whats that ?
i guess i cant just replace the chip , i gotta make a whole new dac circuit with filters and all that is it worth it?

[Chris Daly]

Dear sss

You should view the DAC and Oversampling chip as one
they are a bit like girlfriend and boyfriend the way they
combine ... umm starting to sound saucy

A modern DAC probably wouldnt be compatible and
You could however look at the output opamp
and replace that , invariably this will be a cheap
that will do type that the manufacturer has provided
(washing machine mentality)

You need to define if its a dual or single op amp
singles are much better as they invite less crosstalk
and can be connected with seperate power supplies

Look at OPA134 or AD 847 , and attend to a seperate
regulated supply running at 17volts + and -

Id look at a more recent player for more extensive mods
Pioneer stable platter is a good place to start
and be happy with the service from the Sansui
with upgraded op amps.

Cheers / Chris

[sss]

thanks for the reply Chris
i think the inside dac includes oversampling
can just take the input of the dac and put it into a better - new one?

[Chris Daly]

As I said before the DAC and Oversampling ic
perform as one , inviting a different DAC may not be wise

The output you refer to is not just a
single pin , there are usually 3 seperate
codes happening here called 1. Data 2.LRCK.3 Bitclock

You need to firstly find a schematic diagram to identify
these codes ( Contact Sansui - they may even have a
download , I recall NPC provided me with some simply amazing service getting application data from Japan in about 3 days to australia ).

Generally speaking the three codes will function into
Model X Dac , but there are variables. I would study and
choose a Burr Brown model looking at that application data
Burr Brown may even be able to supply you with a test
board and sample - I know they had a service like this in
the early 90's.

But lets remember all of this is somewhat wasted unless the output opamp is up to the task. So before getting in deep
with changing the DAC change that opamp, give it a seperate
well regulated supply and see what you think.

Cheers / Chris