Hi All,
I recently purchased a used Marantz CD52 unit with the intention to mod it and implement my own non-os DAC module with direct i2s input from the SAA7310GP.
Interesting enough, while tracing the wirings of the SAA7310GP I found that the xtal_in (pin 26) is not connected to any crystal oscillator! The PCB layout is rather intricate and without any service manual on hand, you can imagine it's a tough job trying to put all the pieces together. In any case, I did find a crystall oscillator but it is only connected to the stock DAC chip (SAA7350GP); there's no trace from the DAC XSYS1 pin back to the SAA7310GP.
In case you are wondering about the layout, the DAC chip is connected to a NPC SM5840FP digital filter for up-sampling purpose and it in turn is connected to the micro-controller and the SAA7310GP.
Qn1: The music reporduction of this unit is fine. That seems to imply that it is not necessary for the SAA7310 chip to have have clock input or sync. But...how can this be the case? I mean, surely the SAA7310 chip must need to know when to clock the data out to the Digital Filter/DAC, right?
Qn2: for my mod, I intent to re-use the crystall oscillator and implement the Kwak Clock with clock input to the SAA7310. However, I'm not sure whether this may screw things up. I doubt so but would like some confirmation from the guys who have done mod on Marantz CD52 or with in-depth knowledge of the SAA7310.
Thank you in advance for your help on the above!
I recently purchased a used Marantz CD52 unit with the intention to mod it and implement my own non-os DAC module with direct i2s input from the SAA7310GP.
Interesting enough, while tracing the wirings of the SAA7310GP I found that the xtal_in (pin 26) is not connected to any crystal oscillator! The PCB layout is rather intricate and without any service manual on hand, you can imagine it's a tough job trying to put all the pieces together. In any case, I did find a crystall oscillator but it is only connected to the stock DAC chip (SAA7350GP); there's no trace from the DAC XSYS1 pin back to the SAA7310GP.
In case you are wondering about the layout, the DAC chip is connected to a NPC SM5840FP digital filter for up-sampling purpose and it in turn is connected to the micro-controller and the SAA7310GP.
Qn1: The music reporduction of this unit is fine. That seems to imply that it is not necessary for the SAA7310 chip to have have clock input or sync. But...how can this be the case? I mean, surely the SAA7310 chip must need to know when to clock the data out to the Digital Filter/DAC, right?
Qn2: for my mod, I intent to re-use the crystall oscillator and implement the Kwak Clock with clock input to the SAA7310. However, I'm not sure whether this may screw things up. I doubt so but would like some confirmation from the guys who have done mod on Marantz CD52 or with in-depth knowledge of the SAA7310.
Thank you in advance for your help on the above!
Hi,
Does your CD-52 have 2 PCBs? One for the PS/Controller/Decoder and another for the Filter/DAC/Output Stage?
If yes, it certainly looks like my CD-62. I don't have the service manual for it (if anyone has, please tell me!) but I made some schematics myself by looking at the traces.
If you don't find the datasheets for the ICs in your player, tell me, I'll send you them
Alex
Does your CD-52 have 2 PCBs? One for the PS/Controller/Decoder and another for the Filter/DAC/Output Stage?
If yes, it certainly looks like my CD-62. I don't have the service manual for it (if anyone has, please tell me!) but I made some schematics myself by looking at the traces.
If you don't find the datasheets for the ICs in your player, tell me, I'll send you them
Alex
moemoe said:
Hi moemoe,
The original crystal was probably connected to the SAA7350.
So you have to connect the KWAK-CLOCK here too!
From there the clock is further linked to the digital filter and digital signal processor.
Just remove the crystal, the two small caps connected to it and the 100k or 1M resistor.
See fig. 12 of the datasheet:
http://www.ultranalog.com/data/frits/saa7350_bw.pdf
BTW instructions for the CD52 are also on www.lcaudio.dk
Hi Elso,
"The original crystal was probably connected to the SAA7350.
So you have to connect the KWAK-CLOCK here too!"
Yes, the crystal is directly connected to the SAA7350. I was able to trace the wirings with the help of the SAA7350 datasheet. However, since I'm going to use my own TDA1541-based non-os DAC, I was thinking of connecting the Kwak Clock straight to the SAA7310. One good reason of doing that, I think, is because I would like to input the clock signal directly to the SAA7310 instead of subjecting it to potential noise as it winds its way along the PCB from the SAA7350 to wherever it's supposed to go.
"From there the clock is further linked to the digital filter and digital signal processor."
No such luck...I look at the layout a few times and there's just no clock input back to the digital filter and the SAA7310. The XTAL_in pin of the SAA7310 is left opened and not linked. The XSYS1 pin of SAA7350 is also left opened and not linked. Frankly, I myself is quite puzzled by this. The only explanation I can think of is that there's a internal VXO inside the SAA7350 that's doing the clocking and synchronisation (at least the datasheet seems to imply this)
"The original crystal was probably connected to the SAA7350.
So you have to connect the KWAK-CLOCK here too!"
Yes, the crystal is directly connected to the SAA7350. I was able to trace the wirings with the help of the SAA7350 datasheet. However, since I'm going to use my own TDA1541-based non-os DAC, I was thinking of connecting the Kwak Clock straight to the SAA7310. One good reason of doing that, I think, is because I would like to input the clock signal directly to the SAA7310 instead of subjecting it to potential noise as it winds its way along the PCB from the SAA7350 to wherever it's supposed to go.
"From there the clock is further linked to the digital filter and digital signal processor."
No such luck...I look at the layout a few times and there's just no clock input back to the digital filter and the SAA7310. The XTAL_in pin of the SAA7310 is left opened and not linked. The XSYS1 pin of SAA7350 is also left opened and not linked. Frankly, I myself is quite puzzled by this. The only explanation I can think of is that there's a internal VXO inside the SAA7350 that's doing the clocking and synchronisation (at least the datasheet seems to imply this)
It is possible to remove the DAC and digital filter and connect the clock direct to the SAA7310. Did once myself when i removed a 7220 dig filter from a player (clock was connected to the 7220, as usual).
However, the xtal needs to be the 11.xx MHz xtal found in those old philips based players.
I cannot imagine that there is nothing connected to pen 26 (unless the 7310 is a DIP version and it is pen 19).
Regards,GuidoB
However, the xtal needs to be the 11.xx MHz xtal found in those old philips based players.
I cannot imagine that there is nothing connected to pen 26 (unless the 7310 is a DIP version and it is pen 19).
Regards,GuidoB
take a multimeter and test if the the 7310's pin 26 (Xtal1 or clock input) is connected to the digital filter's clock output (not to the cristal! look at the filter's datasheet, it certainly has a buffered clock output)
In my CD-62, the 7310's pin 26 seems to be unconnected, but in fact it is, and the PCB trace is under the chip, so not visible
In my CD-62, the 7310's pin 26 seems to be unconnected, but in fact it is, and the PCB trace is under the chip, so not visible
moemoe, datasheet of SM5840 can be found here:
http://www.npcamerica.com/discontinued_part_list.htm
That must be a mistake Elso. I would leave the 100k or 1M in place
The 1k must be omitted. Had some nasty side-effects when the resistor from Xin to Xout wasn't there.
http://www.npcamerica.com/discontinued_part_list.htm
That must be a mistake Elso. I would leave the 100k or 1M in place
The 1k must be omitted. Had some nasty side-effects when the resistor from Xin to Xout wasn't there.
Nast Side Effects?
Hi Jean-Paul,
It depends on whom you consult. Lcaudio does remove the resistor while Audiocom leaves it in place.
I more political correct answer from me would be: don’t remove the resistor but if the CD player goes crazy remove the resistor too.
In my Philips CD931 I removed the 220k resistor without causing any problem.
Glad to be of help
jean-paul said:moemoe, datasheet of SM5840 can be found here:
http://www.npcamerica.com/discontinued_part_list.htm
That must be a mistake Elso. I would leave the 100k or 1M in place
Hi Jean-Paul,
It depends on whom you consult. Lcaudio does remove the resistor while Audiocom leaves it in place.
I more political correct answer from me would be: don’t remove the resistor but if the CD player goes crazy remove the resistor too.
In my Philips CD931 I removed the 220k resistor without causing any problem.
Glad to be of help
?????
I didn't consult any company but it was from experience that I commented. The resistor isn't there for nothing. I made the mistake of removing it once in Marantz CD38 and had the cdplayer going crazy. Tried it again in another type cdplayer with the same resulting problem. The ports at the chip need the resistor but newer chipsets have the resistor in them so you probably won't see one in the schematic. For instance with SAA7220 you definitely will have problems when you remove the 100k.
It should be there and it does no harm so why removing it and thus take unnecessary risks ?
Hi tbklbl,
Yes, I did.
I have just completed my tda1541a-based non-os DAC and have successfully integrated it inside my marantz cd52 using i2s as inputs into the dac. I will post more information on my mod soon.
back to the clock discussion, I am using the kwak clock and feeding the 11.2896MHz signal directly into the Xtal_in of SAA7310. the trace of xtal_in runs underneath SAA7310 (thanks to Bricolo for pointing this out to me). U could either feed the clock into this trace at the appropriate junction or desolder the xtal_pin from the trace and lift the pin slightly above the pcb and feed the clock signal directly into it. I went for the latter. it is not necessary to connect xtal_in and xtal_out via a resistor, my xtal_out is not connected to anything.
I removed the digital filter, digital_out chip (can't remember the chip model code off my head) and the saa7350 dac chip as well.
Let me know if you have more questions.
Best regards,
Moe
Yes, I did.
I have just completed my tda1541a-based non-os DAC and have successfully integrated it inside my marantz cd52 using i2s as inputs into the dac. I will post more information on my mod soon.
back to the clock discussion, I am using the kwak clock and feeding the 11.2896MHz signal directly into the Xtal_in of SAA7310. the trace of xtal_in runs underneath SAA7310 (thanks to Bricolo for pointing this out to me). U could either feed the clock into this trace at the appropriate junction or desolder the xtal_pin from the trace and lift the pin slightly above the pcb and feed the clock signal directly into it. I went for the latter. it is not necessary to connect xtal_in and xtal_out via a resistor, my xtal_out is not connected to anything.
I removed the digital filter, digital_out chip (can't remember the chip model code off my head) and the saa7350 dac chip as well.
Let me know if you have more questions.
Best regards,
Moe
Moemoe,
The CD52 REALLY benefits from the following:
1. Incresae the size of the filter cap immediately after the 7805 regulator to 200uF. This will chnage the blotted bass to something really tight!
2. Identify the secondaries feeding the 7815/7915 for the analogue circuit. Desolder these from the board and solder in a seperate transformer to feed the required AC to the rectifiers for the 7815/7915. This will result in fantastic seperation and detail across the frequency range.
Ryan
The CD52 REALLY benefits from the following:
1. Incresae the size of the filter cap immediately after the 7805 regulator to 200uF. This will chnage the blotted bass to something really tight!
2. Identify the secondaries feeding the 7815/7915 for the analogue circuit. Desolder these from the board and solder in a seperate transformer to feed the required AC to the rectifiers for the 7815/7915. This will result in fantastic seperation and detail across the frequency range.
Ryan
cd52's space is limited
Hi Moe Hsiang,
How do manage to squeeze the TDA1541 nonos dac + separate power supply I presume into the chassis? Do u hav a pcb for the DAC?
I am intending to put a TDA1543 dac build on a veroboard and a similiar Kwak clock cct. Both hav their own power supply. But the space inside cd52 is the problem now to fit them in
Currently i just changed all the BIG Ecap to fresh one as mentioned by Dr. H, and changing the rectifier diode with a parallel cap onto it.
BTW did u trace the path that uses 4 in4002(part no. 6523~26) rectifying cct? I am confused what are them use for. It connected to 2 SMT transistors, C548 transistor, 1 zener and 1 small signal diode and then going nowhere.
Do u aware that there is 2 unmounted regulators (+/- 12Vdc) presume to be used by the TCA0372 and JRC4560 opamp for the laser focus/radial pickup circuitry? Or maybe your cd52MKII already have them mounted.
Hav u trace the ground path to check for ground loop? Initial visual inspection seems to be better than those I saw in philips AK6xx CD player. the AK6xx hav the laser cct ground sharing pull from the processor.
Hi Moe Hsiang,
How do manage to squeeze the TDA1541 nonos dac + separate power supply I presume into the chassis? Do u hav a pcb for the DAC?
I am intending to put a TDA1543 dac build on a veroboard and a similiar Kwak clock cct. Both hav their own power supply. But the space inside cd52 is the problem now to fit them in
Currently i just changed all the BIG Ecap to fresh one as mentioned by Dr. H, and changing the rectifier diode with a parallel cap onto it.
BTW did u trace the path that uses 4 in4002(part no. 6523~26) rectifying cct? I am confused what are them use for. It connected to 2 SMT transistors, C548 transistor, 1 zener and 1 small signal diode and then going nowhere.
Do u aware that there is 2 unmounted regulators (+/- 12Vdc) presume to be used by the TCA0372 and JRC4560 opamp for the laser focus/radial pickup circuitry? Or maybe your cd52MKII already have them mounted.
Hav u trace the ground path to check for ground loop? Initial visual inspection seems to be better than those I saw in philips AK6xx CD player. the AK6xx hav the laser cct ground sharing pull from the processor.
tbklbl,
The space is indeed limited, it's made worse with the plastic sturcture above the pcb. So what I did was I placed my pcbs on top of the sturcture. The seperate psu for my DAC is housed outside the cd player box, in another chassis. You might want to give this approach a serious thought.
My dac pcb is hard-wired, not pre-fabricated. I know it is hard work but there wasn't an all-in-one schematic that I liked from the start and my complete design kind of evloved with time. I think there are a couple of shops @ Sim lim Tower that may help fabricate pcb based on given schematic but I have yet to approach them.
so far, my mod is only conc on replacing the dac (with kwak clock and DEM reclocking) and analog output stage of the cd52. I have not gotten around to modify the cd player's psu which is currently used for the transport/uP/servo chip. The kwak clock and dem reclocking draw power from the cd player's psu as well.
I didn't really study the cd player's psu closely but I would presume that the rectifiers (and they fact that there are 4 of them) are there as rectifiying bridge to convert AC to DC. It doesn't seem possible that there are no onward connections. Like initially, I thought the xtal_in of saa7310 wasn't connected to any trace when in actual fact it was running underneadth the chip. I will probably perform cd player psu mod when I get around to doing it. Dr H, thanks for the suggestions. I will look into them
I haven't been paying much attention to the ground path. But I intend to do so. A dread phenomenen I notice is that there's noise pick-up when I connect my dac's rca outputs to my amp. This noise is clearly audible when the interconnect is tightened to the left rca connector of my dac. However, as if by some voodoo magic, when i loosen the connection so that it is just touching the left rca connector, the noise goes away. The right rca connector is ok.
Regards,
Moe
The space is indeed limited, it's made worse with the plastic sturcture above the pcb. So what I did was I placed my pcbs on top of the sturcture. The seperate psu for my DAC is housed outside the cd player box, in another chassis. You might want to give this approach a serious thought.
My dac pcb is hard-wired, not pre-fabricated. I know it is hard work but there wasn't an all-in-one schematic that I liked from the start and my complete design kind of evloved with time. I think there are a couple of shops @ Sim lim Tower that may help fabricate pcb based on given schematic but I have yet to approach them.
so far, my mod is only conc on replacing the dac (with kwak clock and DEM reclocking) and analog output stage of the cd52. I have not gotten around to modify the cd player's psu which is currently used for the transport/uP/servo chip. The kwak clock and dem reclocking draw power from the cd player's psu as well.
I didn't really study the cd player's psu closely but I would presume that the rectifiers (and they fact that there are 4 of them) are there as rectifiying bridge to convert AC to DC. It doesn't seem possible that there are no onward connections. Like initially, I thought the xtal_in of saa7310 wasn't connected to any trace when in actual fact it was running underneadth the chip. I will probably perform cd player psu mod when I get around to doing it. Dr H, thanks for the suggestions. I will look into them
I haven't been paying much attention to the ground path
. But I intend to do so. A dread phenomenen I notice is that there's noise pick-up when I connect my dac's rca outputs to my amp. This noise is clearly audible when the interconnect is tightened to the left rca connector of my dac. However, as if by some voodoo magic, when i loosen the connection so that it is just touching the left rca connector, the noise goes away. The right rca connector is ok. Regards,
Moe
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