Hello Folks,
Can anyone tell me how to upgrade my CD850 MK1 player ?
I only want to upgrade its DAC part but not sure to choice which ways that will have a best sound outcome.
1) to modify it original DAC (which things to replace and wiring modification need)
2) just to replace the modern DAC (any suggestion for me )
Also I want to have its schematic , can anyone help ?
CK Wong
Can anyone tell me how to upgrade my CD850 MK1 player ?
I only want to upgrade its DAC part but not sure to choice which ways that will have a best sound outcome.
1) to modify it original DAC (which things to replace and wiring modification need)
2) just to replace the modern DAC (any suggestion for me )
Also I want to have its schematic , can anyone help ?
CK Wong
I've got the service manual, send me a message with an email address capable of accepting a 3MB attachment.
It's an interesting CD player, using two SAA7321 DACs in a differential configuration. The first thing I would do with this player is recap it. Its got to be at least 15 years old, and will need it.
As for the possibility of connecting it to a new DAC; it is certainly possible, the player uses I2S for the internal digital bus, and has an S/PDIF output, either of which are useful for an aftermarket DAC. However, I would try it out with the original DAC in place first, you might like it!
It's an interesting CD player, using two SAA7321 DACs in a differential configuration. The first thing I would do with this player is recap it. Its got to be at least 15 years old, and will need it.
As for the possibility of connecting it to a new DAC; it is certainly possible, the player uses I2S for the internal digital bus, and has an S/PDIF output, either of which are useful for an aftermarket DAC. However, I would try it out with the original DAC in place first, you might like it!
One more question about the DAC connection. This CD-Player seems too complicate I don't know how to extract its I2S port connect with my DAC1955
http://www.feverhifi.com/thread-1105-1-1.html
Over there I know if use I2S , I need to know what the clock of this CD player's transport . Is it a 11.2896MHz or 16.9344MHz or 8MHz ?
http://www.feverhifi.com/thread-1105-1-1.html
Over there I know if use I2S , I need to know what the clock of this CD player's transport . Is it a 11.2896MHz or 16.9344MHz or 8MHz ?
Like most Philips CD players, the clock is 256Fs, or 11.2896MHz.
Where you capture I2S depends on whether you want to use the SAA7220 digital filter or not.
Are you intending on using the DAC1955's clock generator? And are you planning on installing the DAC into the CD player, or into a separate case?
Where you capture I2S depends on whether you want to use the SAA7220 digital filter or not.
Are you intending on using the DAC1955's clock generator? And are you planning on installing the DAC into the CD player, or into a separate case?
I will use this additional board I2S for DAC1955PRO (I2S support both I2S & s/PDIF I/O)
Is it below only the adapter for I2S ? So I need to buy additional broad with SAA7220 ?
http://www.feverhifi.com/viewthread.php?tid=1067&extra=page=1
If DAC + I2S broad cannot fit inside my CD player , I will trying to use another small case to house them.
Quoted : Are you intending on using the DAC1955's clock generator?
I can find the additional broad DAC1955PRO I2S has the oscillator. Also I think the DAC1955 can provide the clock. Then how can I choose among them.
Can you suggest a good method for me ?
Thanks to your support in advance !!
Is it below only the adapter for I2S ? So I need to buy additional broad with SAA7220 ?
http://www.feverhifi.com/viewthread.php?tid=1067&extra=page=1
If DAC + I2S broad cannot fit inside my CD player , I will trying to use another small case to house them.
Quoted : Are you intending on using the DAC1955's clock generator?
I can find the additional broad DAC1955PRO I2S has the oscillator. Also I think the DAC1955 can provide the clock. Then how can I choose among them.
Can you suggest a good method for me ?
Thanks to your support in advance !!
Considering what you want to do, I am not convinced that the DAC1955PRO is the right DAC kit for you. It is a well built, solid looking DAC, but the following things would make me not want to use it in your case:
- It is physically quite large. I don't think you are going to have a chance of fitting it into the CD850's case.
- It has a digital receiver section, which is completely unnecessary when using I2S. While this is not directly a bad thing, it adds cost to the kit, meaning you're paying for things you're not using.
- It's a very 'conventional' design. The implementation of the AD1955 appears to be straight out of the datasheet, loads of op-amps. The sound quality will probably be good, but not great, and will depend greatly on what op-amps are used.
I would be looking for a design using a solid state discrete output stage, or a minimalist op-amp one, with just the basic I2S input. That said, I don't know if there are many (any?) kits out there that fits those requirements. I don't build kits much myself, so I'm not really up to speed with what's out there at the moment, maybe another member could suggest a suitable candidate.....
If you do want to go with the DAC1955PRO, say so, and I will post a diagram to show you how to connect it up. The CD850 is an ideal CD player for this type of thing. The I2S bus is easy to get to in this player, and the transport / decoder combo (CDM-4/19 and SAA7310) is excellent (and the same as what I use, in the pair of Arcam Alpha +'s I use as test beds).
Anton
- It is physically quite large. I don't think you are going to have a chance of fitting it into the CD850's case.
- It has a digital receiver section, which is completely unnecessary when using I2S. While this is not directly a bad thing, it adds cost to the kit, meaning you're paying for things you're not using.
- It's a very 'conventional' design. The implementation of the AD1955 appears to be straight out of the datasheet, loads of op-amps. The sound quality will probably be good, but not great, and will depend greatly on what op-amps are used.
I would be looking for a design using a solid state discrete output stage, or a minimalist op-amp one, with just the basic I2S input. That said, I don't know if there are many (any?) kits out there that fits those requirements. I don't build kits much myself, so I'm not really up to speed with what's out there at the moment, maybe another member could suggest a suitable candidate.....
If you do want to go with the DAC1955PRO, say so, and I will post a diagram to show you how to connect it up. The CD850 is an ideal CD player for this type of thing. The I2S bus is easy to get to in this player, and the transport / decoder combo (CDM-4/19 and SAA7310) is excellent (and the same as what I use, in the pair of Arcam Alpha +'s I use as test beds).
Anton
Well, I had a closer look at the CD850, and I noticed a couple of things:
- The SAA7220 digital filter does not actually act as a digital filter in this player, it is just used to provide a S/PDIF output and decode subcode output from the decoder into the mute and attenuate flags.
- The I2S bus runs via a cable in this player. This provides a particularly tidy way to modify the player.
My suggested way to tap the I2S on this player would be:
- Remove the 'audio output' and 'variable headphone' boards completely and set them aside.
- Attach the new DAC board using the now empty header No. 33. Its pinout is as follows:
1) MUTE
2) ATT
3) XSYS
4) XSYS1
5) WS
6) CL
7) GND
8) DA
9) DEC
10) VDD
The MUTE and ATT lines both silence the DAC during start up, track change etc when the audio data may be invalid. Most DIY kitsets won't implement this function, so you probably won't use these lines.
The XSYS line provides a 11.2896MHz system clock to the motherboard. This is where you will connect the output of the clock module. XSYS1 is the ground for that signal, and should be connected to the clock module's ground.
WS, CL and DA form the I2S bus. They are the word clock, bit clock and serial data lines respectively.
GND is, obviously, ground. This should be connected to the DAC board's ground.
DEC is the de-emphasis line. Again, most DIY kitsets won't implement this function, so you probably won't use this line.
VDD provides a +5v supply. You could use it to power something, but you probably won't need it.
The whole lot should look like the picture attached below:
- The SAA7220 digital filter does not actually act as a digital filter in this player, it is just used to provide a S/PDIF output and decode subcode output from the decoder into the mute and attenuate flags.
- The I2S bus runs via a cable in this player. This provides a particularly tidy way to modify the player.
My suggested way to tap the I2S on this player would be:
- Remove the 'audio output' and 'variable headphone' boards completely and set them aside.
- Attach the new DAC board using the now empty header No. 33. Its pinout is as follows:
1) MUTE
2) ATT
3) XSYS
4) XSYS1
5) WS
6) CL
7) GND
8) DA
9) DEC
10) VDD
The MUTE and ATT lines both silence the DAC during start up, track change etc when the audio data may be invalid. Most DIY kitsets won't implement this function, so you probably won't use these lines.
The XSYS line provides a 11.2896MHz system clock to the motherboard. This is where you will connect the output of the clock module. XSYS1 is the ground for that signal, and should be connected to the clock module's ground.
WS, CL and DA form the I2S bus. They are the word clock, bit clock and serial data lines respectively.
GND is, obviously, ground. This should be connected to the DAC board's ground.
DEC is the de-emphasis line. Again, most DIY kitsets won't implement this function, so you probably won't use this line.
VDD provides a +5v supply. You could use it to power something, but you probably won't need it.
The whole lot should look like the picture attached below:
Attachments
Dear Sir,
Thanks to your great comments. Sure this broad with comment , people need to modify something to have nice sound.
I completely know how to make them connect together according to your illustration.
Do you know what advantage of using I2S ?
How about this one from Taiwan ?
http://www.alexchiangaudio.com/shop/goods.php?id=398
***********************************************
You claimed "the transport / decoder combo (CDM-4/19 and SAA7310) is excellent". I have asked some people this is a good product.
If an alternative way to let this player have modification to improve sound quality. Then how can I do ? Please give me advice (any main concerning parts active & passive etc. should I to renew and change)
CK
Thanks to your great comments. Sure this broad with comment , people need to modify something to have nice sound.
I completely know how to make them connect together according to your illustration.
Do you know what advantage of using I2S ?
How about this one from Taiwan ?
http://www.alexchiangaudio.com/shop/goods.php?id=398
***********************************************
You claimed "the transport / decoder combo (CDM-4/19 and SAA7310) is excellent". I have asked some people this is a good product.
If an alternative way to let this player have modification to improve sound quality. Then how can I do ? Please give me advice (any main concerning parts active & passive etc. should I to renew and change)
CK
The main advantage of using I2S is a reduction in complexity, and the benefits this brings. The SAA7310 outputs I2S, and most DIY kitset DACs accept I2S. There is simply no need to convert I2S to S/PDIF and then covert it back to I2S again.
The Taiwanese DAC you suggest suffers from the same things I pointed out already, except it does not have an I2S input, so is even worse! Maybe you should go with the first kit, the DAC1955PRO.
To improve the parts of the CD player you will still be using, you will need to recap it. Most caps you can replace with equivalent 105oC general purpose caps, such as the Nippon Chemicon (NCC) KMG series (these are what I use). Replace the caps that decouple the more critical ICs (TDA8808, TDA8809, SAA7310, etc.) with equivalent low ESR 105oC caps, such as the NCC LXY series. Replace the cap that decouple the SAA7220 IC with a super low ESR solid polymer type, such as a NCC PSA series.
The Taiwanese DAC you suggest suffers from the same things I pointed out already, except it does not have an I2S input, so is even worse! Maybe you should go with the first kit, the DAC1955PRO.
To improve the parts of the CD player you will still be using, you will need to recap it. Most caps you can replace with equivalent 105oC general purpose caps, such as the Nippon Chemicon (NCC) KMG series (these are what I use). Replace the caps that decouple the more critical ICs (TDA8808, TDA8809, SAA7310, etc.) with equivalent low ESR 105oC caps, such as the NCC LXY series. Replace the cap that decouple the SAA7220 IC with a super low ESR solid polymer type, such as a NCC PSA series.
Hi Anton
I also have a CD 850 I have decided to upgrade/restore? I have noted your comments regarding replacing the electro caps. If you have any other thoughts about possible improvements please do share them. I don't think that I will bother "upgrading" the DAC, it sounds ok to me.
I would be pleased if you were willing to let me have a copy of the service manual for the CD 850 Mk1 It'll make the job a lot easier
If so my email is lesliep@adhb.govt.nz
Thanks for your help Anton
Les.
I also have a CD 850 I have decided to upgrade/restore? I have noted your comments regarding replacing the electro caps. If you have any other thoughts about possible improvements please do share them. I don't think that I will bother "upgrading" the DAC, it sounds ok to me.
I would be pleased if you were willing to let me have a copy of the service manual for the CD 850 Mk1 It'll make the job a lot easier
If so my email is lesliep@adhb.govt.nz
Thanks for your help Anton
Les.
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