Hi🙂
Last time I read about modding SONY CDP-227ESD to NONOS by omitting digital filter and delaying digital signal by 7 bits straight to DA TDA1541 with excellent results.
Experienced autor declared unbelievable sound: sony227ESD
I would like to do the same with SONY CDP-228ESD, but its DA is made of PCM85 excellent chip, which is 18 Bit.
So it looks like digital filter in 228ESD adds 2 Bits and omitting it became impossible…
Do you have the idea if 228ESD can be rebuilt to NONOS without serious surgery?
Thank you in advance for any response and ideas
Last time I read about modding SONY CDP-227ESD to NONOS by omitting digital filter and delaying digital signal by 7 bits straight to DA TDA1541 with excellent results.
Experienced autor declared unbelievable sound: sony227ESD
I would like to do the same with SONY CDP-228ESD, but its DA is made of PCM85 excellent chip, which is 18 Bit.
So it looks like digital filter in 228ESD adds 2 Bits and omitting it became impossible…
Do you have the idea if 228ESD can be rebuilt to NONOS without serious surgery?
Thank you in advance for any response and ideas
Yahoo couldn't find me the DS for PCM85 and I've never heard of it before. Is it a typo or do you have any more details?
Attachments
If you have the Sony's schematic you're welcome to send it, I'll take a peek to see what might be possible. Going NOS you'll want to remove any opamp I/V and go passive.
please find attached schematics.🙂 the service manual has >6 MB and is secured. I will try to send better pictures later.
This was my intention too, maybe with 6SN7 tube🙄
Attachments
From a quick browse through those, it looks like there are two digital filters - first the CXD1244 then a CXD8003. I can't find a datasheet for the 8003.
Input to the 1244 is in EIAJ (perhaps called 'Sony') format which is incompatible with feeding two mono DAC chips. So you'd need to either design some logic to de-multiplex the data stream or alternatively program a CPU/DSP with the requisite serial ports to do it. Neither approach is trivial.
Input to the 1244 is in EIAJ (perhaps called 'Sony') format which is incompatible with feeding two mono DAC chips. So you'd need to either design some logic to de-multiplex the data stream or alternatively program a CPU/DSP with the requisite serial ports to do it. Neither approach is trivial.
Thank you
unfortunately I do not know nothing about digital/formats/logic, I cannot make it by myself, so I will leave it as it is and make the best possibly power supply for those chips.
I haven't read the thread myself but you might find something useful to you here - http://www.diyaudio.com/forums/digi...1541-fifo-universal-i2s-pcm-driver-board.html
Hi Pawel,
Read your request on the other I2S-PCM thread... (if understanding some simple timing diagrams qualifies us as experts then we really are 😀 )
Had a quick view on what you would like to do... and have to join abraxalito's answer: "you'd need to either design some logic to de-multiplex the data stream or alternatively program a CPU/DSP with the requisite serial ports to do it. Neither approach is trivial. "
The other thread has an I2S-PCM converter, that is not useable for you since you have Sony format (24 bit right justified) not I2S.
The single _costly_ solution that would work for you out of the box is to use Ian's FIFO kit (the default with single clock) + I2S-PCM board.
Since firmware v3.80 FIFO optionally supports 16bit or 24bit (per channel) right justified input format and will output 32bit (per channel) I2S, so you could use I2S-PCM after that.
CXD1244 and CXD8003 are probably in DIP package so you could swap them out and simply use some pin headers to connect cables to FIFO+I2S-PCM board. This solution needs some space that you might not have in your player...
For me this seems overkill for a CD player mod...
Zsolt
Read your request on the other I2S-PCM thread... (if understanding some simple timing diagrams qualifies us as experts then we really are 😀 )
Had a quick view on what you would like to do... and have to join abraxalito's answer: "you'd need to either design some logic to de-multiplex the data stream or alternatively program a CPU/DSP with the requisite serial ports to do it. Neither approach is trivial. "
The other thread has an I2S-PCM converter, that is not useable for you since you have Sony format (24 bit right justified) not I2S.
The single _costly_ solution that would work for you out of the box is to use Ian's FIFO kit (the default with single clock) + I2S-PCM board.
Since firmware v3.80 FIFO optionally supports 16bit or 24bit (per channel) right justified input format and will output 32bit (per channel) I2S, so you could use I2S-PCM after that.
CXD1244 and CXD8003 are probably in DIP package so you could swap them out and simply use some pin headers to connect cables to FIFO+I2S-PCM board. This solution needs some space that you might not have in your player...
For me this seems overkill for a CD player mod...
Zsolt
- Status
- Not open for further replies.