TDA1541 DEM reclocking

Attached find the Grundig schematic.
I currently use 8u smt polymer caps soldered right on the 1541a pins, and a Riken carbon resistor to the WS pin for clock signal.

Here is a useful thread where I first learned about modifying a tda1541a dac.
Arcam Alpha mods but the caps now used are better.

I even share an old pic of my first prototype using 220nU film caps to prove this does not need to be neat to sound great. I also put a choke between the +15v pin and the DEM circuit to keep each other from poluting the other's power supply. The big red cap is a BG N right on 15V. No wonder it sounds so good. Forgot that is under there!

so the images in this post fom page 26, I take it the red line is the new work required to do the grundig dem mod?

cheers adie
 
Re Grundig

It has been a really long time since I did this... but yes the red lays out the mod... a lot of the red is already in place so you'll have to figure it out for your mod.
FWIW, I still think the Grundig mod is excellent. ECDESIGNS 100hz DEM may be better. That is what I now use, but I have not done an A/B comparison to the Grundig design.
 
this image then, it looks like the diagram but does it have an extra capacitor? the upper one of the two.
 

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In EC Design DEM reclockin the value that works best for you has to be found by try & error according the dashboard John published about the cap/resistor value. The 100 Mhz didn't work for my hifi. Anyway a air cap trim pot should be insert to lock and ask an osci. This is a refinment vs the first thing that shoud be done on a cd player, like the main clocking, the powersupply, the work on reg nd I/V + buffer.
Imho you don't start by the DEM reclocking to improve your sound : you finish by such tweaks after the main improvments for voiving little by litttle your DAC; CD player. Btw adie moore I answered your thread in the digital line section as a road-map for "beginners" as I don't know your knowledge level so answered as if it was the first time you tweak a cd player. If so I insist to try on a less ambitious tda1541a to improve skills first : polarity errors, shorts , etc come fast nd can break the cdplayer without possible fix. If not ignore the advice.
 
If it's the Henk ten Pierick who used to be my colleague, and I think it is, then he deceased quite suddenly in November 2013.

Edit: I hadn't noticed yet that it is a very old thread.

I am very sad to hear that! :(
I remember long time ago when Henk T. P. was so supportive and willing to help about many things and DEM reckl.
...Neka mu je laka zemlja...