I have a very nice old CD player (Xindak MUSE 1.0 Tube from 2005)
This player has 96/24 DAC and tube on the analogue output.
I wish that there was a way to ad optical/coax in to this CD player to make use of the DAC and tube output from my other digital devices like that Airport Express.
Does anyone know if this is possible, or how much time this would require from someone with the knowhow?
I have seen several threads about this topic on other CD players, and think that it seems doable, even if i lack the skills with the circuits i can easily handle the soldering and other such related stuff.
I added some images, of the text where the CD transport connects to the DAC/analoug part of the PCB.
Anyone knows if there is simple I2C connection here (or what it is called) or if another solution is possible? I am very thankful for any insights.
//GF
This player has 96/24 DAC and tube on the analogue output.
I wish that there was a way to ad optical/coax in to this CD player to make use of the DAC and tube output from my other digital devices like that Airport Express.
Does anyone know if this is possible, or how much time this would require from someone with the knowhow?
I have seen several threads about this topic on other CD players, and think that it seems doable, even if i lack the skills with the circuits i can easily handle the soldering and other such related stuff.
I added some images, of the text where the CD transport connects to the DAC/analoug part of the PCB.
Anyone knows if there is simple I2C connection here (or what it is called) or if another solution is possible? I am very thankful for any insights.
//GF
Attachments
You would need to find out which chip is the DAC chip. If you write down all the part numbers on the chips and google each one to find the data sheet for that chip, eventually you will find a data sheet that describes the chip as a DAC.
Its the circuitry right around that chip you would need to tap into. However, you would need to add some other parts, maybe build a small circuit board and a power supply for it in order to do conversion from SPDF/TOSLINK to the I2S signals the DAC chip needs.
If you consider all the work involved to do what you are thinking about, there is no way it makes sense given the time and effort involved. If you just want to do it because you think it would be a fun way to spend time, then maybe. You should also have an oscilloscope and know how to use it.
Another thing to consider is that DAC technology keeps getting better and better as time goes on, it just happens very slowly. But 15 years is plenty of time for much better sounding DACs to become available. Probably makes the most sense to spend time, effort, and other resources directed towards finding a newer technology replacement DAC that will do everything you want.
Its the circuitry right around that chip you would need to tap into. However, you would need to add some other parts, maybe build a small circuit board and a power supply for it in order to do conversion from SPDF/TOSLINK to the I2S signals the DAC chip needs.
If you consider all the work involved to do what you are thinking about, there is no way it makes sense given the time and effort involved. If you just want to do it because you think it would be a fun way to spend time, then maybe. You should also have an oscilloscope and know how to use it.
Another thing to consider is that DAC technology keeps getting better and better as time goes on, it just happens very slowly. But 15 years is plenty of time for much better sounding DACs to become available. Probably makes the most sense to spend time, effort, and other resources directed towards finding a newer technology replacement DAC that will do everything you want.
Hello!
Thanks for your reply, that is a true insight you have there about time and money invested.
I was thinking its possible to tap in between the CD transport and the PCB, that if one knows the output signals of the CD transport it would be best place to tap into the signal chain, or am i wrong about this? (there is a flat ribon cable there on the pictures, and also all the pins on the connector is clearly marked)
Is there any way to know if the signal from the transport of the CD is I2S or if it is another format?
How many hours do you think it would be for a experienced audio DIY person to do this mod? If i would like to pay for the design but execute the work myself?
Thanks again!
Best regards
/GF
Thanks for your reply, that is a true insight you have there about time and money invested.
I was thinking its possible to tap in between the CD transport and the PCB, that if one knows the output signals of the CD transport it would be best place to tap into the signal chain, or am i wrong about this? (there is a flat ribon cable there on the pictures, and also all the pins on the connector is clearly marked)
Is there any way to know if the signal from the transport of the CD is I2S or if it is another format?
How many hours do you think it would be for a experienced audio DIY person to do this mod? If i would like to pay for the design but execute the work myself?
Thanks again!
Best regards
/GF
Modifying a CD player for receiving an external digital input is fraught with difficulties even for relatively experienced engineers. Its really not a suitable project for someone who on their own admission lacks skills with circuits.
The key difficulty is that a CD player is a clock master - meaning it contains a crystal which the output from the disk is synchronized to. A DAC receiving an external S/PDIF signal is necessarily a clock slave - the transmitter of the data is the master. Trying to convert a device which is designed as a clock master into a clock slave is a significant re-design and most certainly isn't for those without a good grasp of digital audio systems.
The key difficulty is that a CD player is a clock master - meaning it contains a crystal which the output from the disk is synchronized to. A DAC receiving an external S/PDIF signal is necessarily a clock slave - the transmitter of the data is the master. Trying to convert a device which is designed as a clock master into a clock slave is a significant re-design and most certainly isn't for those without a good grasp of digital audio systems.
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Ok!
So basically it is very difficult to make a circuit that "emulates" the CD transport device and hooks up in between the units for this reason? Am i understanding this correct?
So there is some circuit further down the road, from the CD transport, that converts the CD transport signal to I2S? And then the I2S signal is fed into the DAC?
Thanks for interesting points!
//GF
So basically it is very difficult to make a circuit that "emulates" the CD transport device and hooks up in between the units for this reason? Am i understanding this correct?
So there is some circuit further down the road, from the CD transport, that converts the CD transport signal to I2S? And then the I2S signal is fed into the DAC?
Thanks for interesting points!
//GF
Just to be sure here, the markings on the PCB indicates:
TX
OGND
MUT/L
MUT/R
SCLK
DAT
CLK
BCK
DGND
NC
And even with these markings there is still no indication of how the communication protocol is setup? These markings does not tell any important things about how data is formatted or how to hook up other source of data here?
Thanks!
TX
OGND
MUT/L
MUT/R
SCLK
DAT
CLK
BCK
DGND
NC
And even with these markings there is still no indication of how the communication protocol is setup? These markings does not tell any important things about how data is formatted or how to hook up other source of data here?
Thanks!
IC217 and IC218 positions are marked as D/A but empty. Perhaps on the underside? Also there are many hints on the PCB like markings: SCLK, BCK, WS, DATA. These must be I2S signals but you'd need an oscilloscope (DSO) to step further.
Hello!
Yes, if you look on the other pictures, you can se the corresponding IC's that is located under the PCB.
I tried to lift it and take pictures on the underside, but i couldnt disconnect all the cables and remove the PCB completly at that time.
Its difficult to read out all the numbers on the DAC IC's, but it is showing all of them on the images attached in first post.
Ill try to read out some of them, however some signs are hard to read:
TDA1305T
K7D394
HSH0334 4
74**00D
AW634 34
URG0550H
74*86D
AG830 06
Un03520
74HC1640
AX550 41
UR60605C
74HC74D
AW997 18
UN606014
74HM**4D
A*****57
UN60525C
Are these the DAC IC's, or some other kind of IC's?
Yes, if you look on the other pictures, you can se the corresponding IC's that is located under the PCB.
I tried to lift it and take pictures on the underside, but i couldnt disconnect all the cables and remove the PCB completly at that time.
Its difficult to read out all the numbers on the DAC IC's, but it is showing all of them on the images attached in first post.
Ill try to read out some of them, however some signs are hard to read:
TDA1305T
K7D394
HSH0334 4
74**00D
AW634 34
URG0550H
74*86D
AG830 06
Un03520
74HC1640
AX550 41
UR60605C
74HC74D
AW997 18
UN606014
74HM**4D
A*****57
UN60525C
Are these the DAC IC's, or some other kind of IC's?
TDA1305T is the DAC being used - the blurb I read said they were using two of them so presumably its a dual-mono approach since that DAC is stereo. It's not really a great performer - if you love it though you can find DAC boards with it on. For example here : MINI ?? ?? TDA1305 DAC ???-???
If I were you I'd install one of these boards in your player (its about $12) and tie its output into your tube buffer. A project with more likelihood of success than unpicking the I2S.
If I were you I'd install one of these boards in your player (its about $12) and tie its output into your tube buffer. A project with more likelihood of success than unpicking the I2S.
<If I were you I'd install one of these boards in your player (its about $12) and tie its <output into your tube buffer. A project with more likelihood of success than unpicking the <I2S.
Now this sounds extremly interesting.
Lets say now that i was trying to hijack the signal chain in the start, before the DAC, just because i want the tube output stage.
Maybe it would be MUCH smarter as you say, to hijack the signal path later and get the tube output only and ditch the DAC, that you describe as "not a great performer".
Thing is that i kind of think it is fun to tinker, and i like to re-use this nice looking CD player, and i really love the tube output. If i can re-use the tube output only, and still get to keep the CD as it is. Is this still possible with the method you describe?
Maybe it would be possible to pick an even better DAC and then output the signal straight to the "tube buffer"?
If i can take the power supply from the CD (there is clear markings of voltage levels) and use the chassie + output of the CD i would be happy. Especially if its still possible to use the CD player as it is, with no cutting of traces on the PCB.
Is this how you intended this done?
Thanks!
//GF
Now this sounds extremly interesting.
Lets say now that i was trying to hijack the signal chain in the start, before the DAC, just because i want the tube output stage.
Maybe it would be MUCH smarter as you say, to hijack the signal path later and get the tube output only and ditch the DAC, that you describe as "not a great performer".
Thing is that i kind of think it is fun to tinker, and i like to re-use this nice looking CD player, and i really love the tube output. If i can re-use the tube output only, and still get to keep the CD as it is. Is this still possible with the method you describe?
Maybe it would be possible to pick an even better DAC and then output the signal straight to the "tube buffer"?
If i can take the power supply from the CD (there is clear markings of voltage levels) and use the chassie + output of the CD i would be happy. Especially if its still possible to use the CD player as it is, with no cutting of traces on the PCB.
Is this how you intended this done?
Thanks!
//GF
Thing is that i dont really understand how these small items (DAC from aliexpress) can replace all of those components and dual channel DAC processing in the old board with same quality of sound? Do these small boards deliver good quality output?
This is another DAC, will it be similar result?
Aliexpress DAC 24/192
Is it possible to use one of the famous products from this site:
MiniDSP
Thanks, this idea sounds most interesting to me right now.
This is another DAC, will it be similar result?
Aliexpress DAC 24/192
Is it possible to use one of the famous products from this site:
MiniDSP
Thanks, this idea sounds most interesting to me right now.
All you need is access to the dac chip, an ability to measure voltages and the datasheet for said dac. That will get you the definitive information you need to determine if the effort is worth it.
If you're not that enamoured of TDA1305 then I'd recommend another DAC board to retrofit into your player.
I like tinkering too but can't follow your question. You want to keep the CD player as a player but upgrade the DAC chip and keep the tube output? Certainly that's possible but I'm not clear that's what you are saying here.
I agree that would be better. But when I suggested a TDA1305 board I didn't know which features of your player you wished to preserve through the upgrade. Hence I kept the same DAC.
You'd need to ascertain what voltages are available internally and make an educated guess about the current capability. If current is a scarce resource you might need to disconnect the existing DAC circuitry in order to accommodate the new. Armed with knowledge of the environment then make a choice about the most suitable DAC board which can exist in that environment.
I think Goodfi is happy with the sound of his xindac as a cd player and now inspired by the thread to add another better? dac inside and connect it to its tube output. This way it will act as a player with extra digital input for his other devices.
edit: This:
Cheers!
edit: This:
- but keeping the existing dac for CD
Cheers!
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