CS4397 dac

Some news:
Capacitors C32 and C33 (original value 56pF) should go out. Op-amp will not oscillate without them :eyebrows:, they are killing highs.
Capacitors C34 and C35 (original value 1nF) should go out. Or minimal value of 100-150pF, as Leo suggested.
C44 and C51: desolder original 100μF, put 47μF.
C40 and C50: leave original SMD, bypass with 0.1μF MKP (small size)

Bottom side of the board:
Solder lytic capacitor 4.7μF or 10μF directly to op-amp legs 4 and 8 (4=negative, 8=positive) for decoupling. Use good quality cap.

This guy did tests and proved that it Improved the highs..
http://theartofsound.net/forum/showp...&postcount=210

Removing those capacitors, are we replacing it with something else? Or just leaving it empty?

Hi
I'm Marco from Germany (sorry for my bad english).
My Kit arrived today.
I compared the "stock"-dac-kit with my CD-Player ( a Sony SCD-XE670).
The only difference I heared was that the DAC is a bit louder than my CDP.
I'm a bit disappointed. Is this normal in "stock"-state?

What is the first thing I could do to improve the Sound?

My equipment:
Sony CDP SCD-XE670
Amp: Rotel RA-931 (I use its headamp)
Sennheiser HD650

Thanks in advance


Marco

Hi Marco, from another Marco :)

Welcome to AOS. Where in Germany are you? My wife has relatives in Köln and Bergisch Gladbach.

Marco.

Quote:

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Originally Posted by Marco

Where in Germany are you? My wife has relatives in Köln and Bergisch Gladbach.

Marco.

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Hi Marco

I live in western Germany. About 100km to Köln and 10km to the Netherlands.

Hi Marco,

Are you anywhere near Euskirchen? My wife also has relatives there. We usually spend a week in Köln and a week in the countryside near where you are :)

I love Germany!

Anyway, we better keep the thread on topic ;) I just popped in to say hello.

Marco.

Quote:

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Originally Posted by Marco

Hi Marco,

Are you anywhere near Euskirchen? My wife also has relatives there. We usually spend a week in Köln and a week in the countryside near where you are :)

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Euskirchen is in the South of Köln. I live in the North (about 100km) of Köln.

Quote:

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Originally Posted by Marco

I love Germany!

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Me too! ;)

Quote:

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Originally Posted by Marco

Anyway, we better keep the thread on topic ;) I just popped in to say hello.

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Yes we should. I think the others are getting nerved by this.


So could anyone make a guide/tutorial or simply a list of what improved the sound? That would be awesome!

I read the whole thread (and also this and this) but I'm a bit confused because some mods are contradictory.
One persons changes Capacitor-A like this and another like that.

Thanks in advance

Marco


P.S.: There is actually no thread in our german hifi-forum. If I suceed with my mods, I will post one.

im gonna try firefly's mod when people start confirming it is good. Yea I am confused too. Leo has 4 capacitors around the opamp when firefly removes 2 of them. And he removes the resistor mods too. Leo hasn't been on in a while, but I will do the mod once he agrees with firefly lol.

Things like PSU's and type of op-amps can cause varying results, I personally don't like Oscon caps in a lot positions yet some others do, as with everything else its best to try it out, if you don't like it, just rip it out;)

I've not tried removing the caps in the op-amps feedback positions yet.
I'm currently using AD826 which can be a little touchy so requires a bit of care
Soon as I get time I'll remove the caps and have a look on the scope

If you remove the the caps and notice excessive brightness this can be a sign of HF distortion caused by ringing, some op-amps shouldn't cause any issues so should be fine

I have capacitors like this except 4uF on my outputs. http://www.parts-express.com/pe/show...number=027-200

It does not show polarity.. can it go any way?