If you're going to feed it S/PDIF why not put it in a separate box?
If you're putting it inside I reckon it is much better to tap into the I2S inside the player and use a TDA1543 (less jitter).
The I2S in this player is non-OS as the oversampling occurs in the digital filter which is inside the original NPC DAC. Good news.
TDA1543 accepts I2S and TDA1545 accepts EIAJ.
Or why not do both and see which sounds the best!
TDA1543 via I2S would not need a receiver...
If you're putting it inside I reckon it is much better to tap into the I2S inside the player and use a TDA1543 (less jitter).
The I2S in this player is non-OS as the oversampling occurs in the digital filter which is inside the original NPC DAC. Good news.
TDA1543 accepts I2S and TDA1545 accepts EIAJ.
Or why not do both and see which sounds the best!
TDA1543 via I2S would not need a receiver...
Thomo said:
So you have 5V on the laser side of C505 and 0V on the decoder side of R509?
The HF pins should be floating at half the supply and the cap C505 should block any DC current flowing between the HF amp and the decoder. I'd check all these parts for shorts.
If your HF amp is fried the cap would save the decoder (and vice-versa).
What do you get either side of R505 (HF amp supply)?
Glenn2 said:
Yup.
It seems to be doing exactly that.
What do you get either side of R505 (HF amp supply)?
4.9v & 5.04v
Thanks for your help Glenn. I think the problem is the hf area. I've measured all resistors but they measure ok. I have replaced the transistors so they should be good. Could it be the caps?
Lee.
Glenn2 said:
Just my point of view. I'd like a one box solution.
At my present skill level I need a complete kit. As long as you keep that limitation in mind I can try anything.
I see where DIY Paradise has a TDA1543 Kit listed but it has SPDIF input as well.
I also see where the much respected Peter Daniel was offering a 1543 kit. AudioSector
I would've really liked to have tried one of Scott Nixon's TubeDAC's but he doesn't offer them in kit form anymore.
Have I missed any other worthy candidates?
Regards,
Dan
dantwomey said:
You could get this PCB and just build the right-hand side!
And looking elsewhere on that site, this chap has done it already.
See this.
He shows you what pins to connect to what resistors on the 63 (but 67 will be easy to adapt). You could trace those pins around to the empty component holes on the receive side for your inputs (or bend pins 1,2 and 3 into the air).
I'm tempted to try that myself - I have an old 63 lying around.
Glenn2 said:
If I want to do an I2S feed directly from the SAA7345 could the solution be as simple as this?
An externally hosted image should be here but it was not working when we last tested it.
Regards,
Dan
Glenn2 said:
Hi Glenn,
I should have been more clear.
My power supply was built with 5 wires coming off it for:
1) DAC clock at RD01
2) DAC digital at RD04
3) DAC analogue at U199
4) Decoder digital at R508
5) Decoder analogue at R511
For my latest test, I just used 2 & 3.
I had connected the ground for the whole power supply board to U170 (but U203 looks like a better option
)BTW I missed out on the EBay CD63
Glenn2 said:
No, these are supplied from 1x12v extra tx. The regs are perfect, I have tried them on another circuit and they are good. Everything worked fabulously until the coax mod!
When you say i'm getting dc both sides of the cap, do you mean c505? If so then I think I got it wrong. I'm getting 4.2v on one side and 0v on decoder side.
Lee