| Cobra2 |
Finally, one is heading my way...
And since a search did not get much results; please give me some upgrade suggestions!
For "integrated" use, op-amps & blocking-caps are obvious.
But what about clock(s)? Witch is most important?
For 1) audio out use? 2) digital out use?
Would maybe a Tent clock with "feedback" be usable here?
(guess not, frequencies does not add up)?
Arne K
P.S.: My Teac VRDS-10 is up for trade / sale...incl.new laser.
(and another new as spare!(KSS-151A). -looking for new KSS-272A ) |
|
|
| Cobra2 |
-but I need some help...
On the audio-board, after the DAC, signal goes to op-amp IC402/502.
On schematics it says "DE-EMPHASIS" on these, and there is no switch....so is the signal filtered for de-emphasis all the time?
Should I remove/modify/bypass the filter?
Arne K |
|
|
| Elso Kwak |
| Hi Arne, I will look it up tomorrow, with a clear head :drunk: |
|
|
| Cobra2 |
Another thing I also noticed...the difference in signal-path; the filtering & buffering of the RCA signal vs the less treated balanced signal...
Arne K |
|
|
| Elso Kwak |
Hi Arne,
That whiskey was not a good idea........
I have a look at the schematic. Deemphasis is simply wrong, should be IV-converter for IC402 & 502.
Balanced out takes a separate route after these IC's.
If you are using the player only as a transport the 16.9344 MHz clock is only important. Digital out will even work with the 45.1584MHz clock disabled if you install a 16.9344 clock.
The 45.1584MHz clock is needed for the Sigma-Delta DAC. When using the player integrated you run across the two clock problem as these two clocks need to be synchronised.
:cool: |
|
|
| Tube_Dude |
| quote: | Originally posted by Cobra2
On schematics it says "DE-EMPHASIS" on these, and there is no switch....so is the signal filtered for de-emphasis all the time?
|
Hi Cobra
Sometimes the switching is done by a Fet or transistor and not by a switch... |
|
|
| Cobra2 |
This time it is a error in the schematics...!
Another error; the balanced output is wrong (+/-)(swapped).
Try also dis-connecting the digital out wiring...it makes a change in sound !???!
I also noticed that the internals are quite warm..a few vent-holes would help!
Arne K |
|
|
| Elso Kwak |
| quote: | Originally posted by Tube_Dude
Hi Cobra
Sometimes the switching is done by a Fet or transistor and not by a switch... |
Deemphasis is done in the digital filter in this Sony model.
:cool: |
|
|
| DragonMaster |
| quote: | | Try also dis-connecting the digital out wiring...it makes a change in sound !???! |
I added a coax out on my Sony CDP-295, if analog is plugged in it at the same time as a coax receiver, the SPDIF signal starts sounding like ****, but if I use my DIY coax 2 mini-optical plug, the signal is OK. |
|
|
| Cobra2 |
DragonMaster,
I ment the internal wire, (it's separate, to a "digital-pcb" in my player).
But it will probably always be best leaving out the wiring you do not use...?
Have just "updatet" a X202ES, new op-amps, a few caps, some damping & weight. It has one of the same Dac-chips as the 779, and does sound allright now.
Arne K |
|
|
| DragonMaster |
| Well, I use both : Analog is plugged in the amp, and coax out to the mini-optical plug for the midi-disc. |
|
|
| rfbrw |
| quote: | Originally posted by Elso Kwak
The 45.1584MHz clock is needed for the Sigma-Delta DAC. When using the player integrated you run across the two clock problem as these two clocks need to be synchronised.
:cool: |
Whenever this 2 clock thing crops up it is always presented as a huge problem. Can't see what all the fuss is about. There is at least one off-the-shelf solution and generating 1024Fs and 384Fs from a single source is not difficult. |
|
|
|
