how to ad digital coax out to cd player without it?

ferninando

Lunatic Member
hope some of you DIYrs can help me.
I need to know what to do to ad a digital coax out put
tp one of my cd players that does not now have one
so I can use an external DAC with digi coax input.
anyone want to tackle this?
any info is appreciated
 
Buy a new CD player with digital out. You need to convert from analog to digital, the quality all depends on the converter even if you have a perfect CD player. You don't want to go into the internal of the CD player to do that, that's likely to be way way way too complicated if even possible.
 
Buy a new CD player with digital out. You need to convert from analog to digital, the quality all depends on the converter even if you have a perfect CD player. You don't want to go into the internal of the CD player to do that, that's likely to be way way way too complicated if even possible.

there are some how can do it no prob. just have to know where to tie in to. .
dont need more new cdps.
need to add coax digital output to existing cdp that does not have one..
I want to be able to use an external DAC, of which I have 2 and getting another.
thanks for the reply .

PS: one CDP is a sony and one is a pioneer
 
This is a non - trivial procedure. There was an article on how to do this years ago in Audio Amateur. You have to add additional circuits.
 
in general, you tap the digital output of the digital signal processor (DSP) - at the junction
where it meets the internal DAC.

look at Harman Kardon hd7500/7600, one has only RCA analog outputs, and the other
has both analog and digital outputs. there's added circuitry for this.
 
As I recall, in the article they said you have to reclock the data. Also you may need to add a buffer because the DSP probably isn't meant to drive the capacitance of a cable.
 
You can make a huge improvement in the sound by replacing the opamps in the filter and final stage of the CD player. The internal DAC is usally very good, but the opamps garbage up the sound. Sony used lousy opamps in their players. You can replace them with a drop in replacement; LM4562 and the sound will rival a high end player. This is usually the reason for lackluster sound in CD players.
 
dr*audio is absolutely correct. and this is the easiest way.

alternatively, if you are really serious about this, read all 700+ pages at diyaudio on digital sources
you'll get everything on I/V conversions, reclocking, adding DACs, oversampling, etc.

AK is great for specific information on a given CDP. and of course, the great tips on fixing CDP
from dr*audio.

I have two CDPs from the golden age that have implemented DACs using discrete components
and will probably do the same as you - time and energy permitting.
 
I am going to put the LM4562s in my sony 302, the one with no digital coax output..
Just to see what happens, using sockets for kwik change.
BUT, Due to the incredible complexity of the circuits, that without a PHDEE degree, it appears
that installing a digital coax out is a futile exercize and I dont think I will persue it any further.
Unless someone can give me all the technical info needed to do it. More web searching .
That HK 7600 is a true nitemare.

PS: I will look more at diyaudio for sure.

thanks to all for the info.
 
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there were kits that you "attach" to your CDP main board. some came as parts and some
came as finished boards.

how is the HK 7600 a nightmare. there are two places where they attach a transformer
and another where there's a circuit for both types of digital outputs. don't let the parts
count deter you - you're not touching the rest of the circuit only tapping the DSP output.

compare the 7500 (no digital outputs) and the 7600 with digital outputs. It doesn't get
simpler than what I described above - two parts with maybe a dozen solder points
including most of the hard work in punching through the back panel and adding
connectors and labels.
 
Bob, I really apppreciate your encouragement.
I am gonna let it go for now and maybe wait and see what someone has actually done that works
without any problems.
I appreciate everyones info. thanks.
 
On the CDP-302, also tighten the screws that secure the pc board. Sony used those screws to complete the ground path. They get loose over time and the sound degrades. Highs sound mushy.
 
but even new ones do not always provide digital outputs.
and I know to look for them when shopping and never get one without.
 
and then there's the models that play both CD and SACD, CDs output both the digital and
the analog, but the SACD comes only through the analog which you means you are
chained to the quality of the built-in DAC. the good news is that the DAC was chosen to
support the DSD (and who knows what DSD to LPCM to analog conversions along the way)
and CD was dragged along.
 
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