MK2703 PLL clock in SACD, good or no good?

[tubee]

I have a Yamaha S657 SACD/DVD/CD upsampling player. Have downloaded the service manual to look at the schematics. (philips DVP 720 is allmost the same)

The clock is provided by a PLL chip, the Audio Clock Synthesiser MK2703. Is this any good?

Another SACD player, the Philips DVP 963SA has 3 cristals which are switched (But switching of clock signals is not the best way imo)

What can possibly done to mod the clock of this Yamaha SACD player? I only can think of good bypassing with sanyo oscon near PLL chip.

[Guido Tent]

Originally posted by tubee
I have a Yamaha S657 SACD/DVD/CD upsampling player. Have downloaded the service manual to look at the schematics. (philips DVP 720 is allmost the same)

The clock is provided by a PLL chip, the Audio Clock Synthesiser MK2703. Is this any good?

Another SACD player, the Philips DVP 963SA has 3 cristals which are switched (But switching of clock signals is not the best way imo)

What can possibly done to mod the clock of this Yamaha SACD player? I only can think of good bypassing with sanyo oscon near PLL chip.

it provides the correct frequencies (good), but jitter wise..........

Neverthjeless, these PLL chips provide better clocks if their source is better: Replace the standard crystal attached to these ICs with a better clock and you will bennefit. Decoupling helps, but better take a separate regulator for the PLL chip.

best

[JonHarrison]

Hi Tubee,

Do you have a url link for the S657 manual? I have the DVP720SA manual and would be interested to review the Yamaha.

Presumably this is another co-design like the DVP9000SA / S2500 ?

Cheers,

Jon

[tubee]

Hi Guido

I was hoping allready that you could reply to this question, thanks a lot.

Didn't open the player, but saw indeed in the datasheet of PLL a cristal is used, the block diagram of Philips DVP720 didn't mention about a cristal. I thought the frequency was defined by the PLL chip only. Will upgrad clock to PLL, and build separate (& choked) PS for it.

Hi Jon.

Yamaha S657 has used same Philips mainboard of Philips DVP720, but omitted the eco board and has another keyboard pcb. I could only find 720's serv. manual.

[tubee]

The PLL uses MCL from mechanism, and buffers it. No cristal near PLL used, but there must be a cristal found somewhere, i assume near DVD mechanism.
Opamps used: LM833, yuk. Should try LM4562's

[tubee]

Here 27Mhz clock source.

[Guido Tent]

Originally posted by tubee
The PLL uses MCL from mechanism, and buffers it. No cristal near PLL used, but there must be a cristal found somewhere, i assume near DVD mechanism.
Opamps used: LM833, yuk. Should try LM4562's

mcl from mechanism, yuck....

I wouldn't spend too much money, other than to see if replacing the master clock on the mechanism, improves anything

best

Guido

[tubee]

I wouldn't spend too much money, other than to see if replacing the master clock on the mechanism, improves anything

Thanks for tips Guido.
But this player doesn't sound bad at all out of the box. The cristal freq. must be tapped somewhere else, that's problably why they used a PLL chip afterall.

[tubee]

I couldn't hold myself any longer, lifted the hood of the Yamaha. 3 pcb's, switching PS, mainboard and mecanism board. Opamps are 4 smd LM833,s
One cristal: 27000 ceramic smd(27Mhz) near mechanism.
What i could do is build a new and simple oscillator, buffer it with 3 And gates and lead the 3 clock signals to the parts who need it.

And what about this very simple clock: (found it on diyaudio somewhere else)

[Guido Tent]

Originally posted by tubee

And what about this very simple clock: (found it on diyaudio somewhere else)

Textbook design, hence no good for serious audio. And no suggestion for a a slicer.......

cheers