Upgrade output Shanling CD-S100 MkII

[CeeVee]

The 3u3 caps, should they be nonpolar ?

[Zen Mod]

Originally posted by CeeVee
The 3u3 caps, should they be nonpolar ?

for test - irrelevant
use whatever you have , even mixed (few in parallel )

everything from 3u3 up will do the job .

hehe - just try to have same caps in all 4 legs ........

NB - point of test is to hear have you gained in clarity and "singing "

frequency extremes should be better in final variant , when we adjust all impedance and voltage/current conditions

edit : whatever caps you use - it can't be worse than it is now

OPA xxx ........... gimme a break .........

[CeeVee]

Ok ZM,

Test is done, as for level...i don't see much difference...with or without op-amps, so DAC easily drives UGS.

Guess that is why there is one more Resistor going from pin DAC 20 to both op-amps, one each to where pins 2 and 3 are connected to each other ( this is not in the app-note schematic ).

In terms of tone.....oh yes much better, although ofcourse there is distortion at top end but tone is much more open and true.
Distortion is i guess due to the "beautifull" rat's nest.

I can now believe the piano in Diana Krall's CD, sounds right...and this has been my reference all along, before it sounded dull, not as a piano should, sharp and clean...up front.

by the way i have all same components in both channels.

[Zen Mod]

Originally posted by CeeVee
Ok ZM,

Test is done, as for level...i don't see much difference...with or without op-amps, so DAC easily drives UGS.

Guess that is why there is one more Resistor going from pin DAC 20 to both op-amps, one each to where pins 2 and 3 are connected to each other ( this is not in the app-note schematic ).

In terms of tone.....oh yes much better, although ofcourse there is distortion at top end but tone is much more open and true.
Distortion is i guess due to the "beautifull" rat's nest.

I can now believe the piano in Diana Krall's CD, sounds right...and this has been my reference all along, before it sounded dull, not as a piano should, sharp and clean...up front.

by the way i have all same components in both channels.

OK - while you still have rat's nest - try to vary our I/V resistor values - say - from 820 to 2K2 ...... and try to find value where overall sound is at best ;

you can also try to decrease these 4n3 caps ...... gradually to 2n7

hehe

just for my pleasure - give me few pics of rat's nest ........

[CeeVee]

Of course ZM,
I'll post today's rat's nest in awhile but more tests only for tomorrow.
I'm preparing for a conference next week....I'll be all week in Oostende ( north Belgium ) but i'll be able to do a few more tests until Thursday...after that it's a whole week for your fertile mind to think on the issue...along with all others here of course.

[CeeVee]

A closer look.

Just a thought; i did not lift the caps in parallel with the resistors,

Guess i need to do this and test again.
Also maintained the 100n caps to ground.

[Zen Mod]

Originally posted by CeeVee
Of course ZM,
I'll post today's rat's nest in awhile but more tests only for tomorrow.
I'm preparing for a conference next week....I'll be all week in Oostende ( north Belgium ) but i'll be able to do a few more tests until Thursday...after that it's a whole week for your fertile mind to think on the issue...along with all others here of course.

on second thought - try altering values of those 4n3 first , and later try to alter values of resistors ;

bon voyage ....... in any case ........ (manu - did I wrote it OK ?)

[Zen Mod]

Originally posted by CeeVee
A closer look.

Just a thought; i did not lift the caps in parallel with the resistors,

Guess i need to do this and test again.
Also maintained the 100n caps to ground.

I didn't saw that post of yours , while typing previous .....

be sure that output pins at DAC are completely free of any load ( form original circuit ), be it cap or resistor

you remember that I don't know exactly how that output configuration looks in Drekling .......

100n to ground ?
where ?

[CeeVee]

don't wish me bon voyage yet...you will here more from me this week before i go.

I'm the one that can´t wait to hear the Shanling singing properly.

On a curiosity note: i was looking at the Shanling CD-200T board, a picture on the web....and you would not believe it..., same DAC but more interestingly...same output, even board layout.

..cookbook ?

...100n on board are the C11, C12 and C21, C22 on schematic you posted from data sheet.
They are still in, should i lift them as well to have a clean output from the DAC ?

What i'll do before i go is post an exact schematic, ill get it from the PCB by tomorrow, np.

[Zen Mod]

Originally posted by CeeVee
don't wish me bon voyage yet...you will here more from me this week before i go.

I'm the one that can´t wait to hear the Shanling singing properly.

On a curiosity note: i was looking at the Shanling CD-200T board, a picture on the web....and you would not believe it..., same DAC but more interestingly...same output, even board layout.

..cookbook ?

you can give me that link ....

anyway - if you wanna Cook Book and dedicated output stage , you must send me one - for testing and later proper disposal ........

Originally posted by CeeVee

...100n on board are the C11, C12 and C21, C22 on schematic you posted from data sheet.
They are still in, should i lift them as well to have a clean output from the DAC ?

What i'll do before i go is post an exact schematic, ill get it from the PCB by tomorrow, np.

desolder them promptly ; they're choking output in our raw topology.