Help me mod Philips CD960

[@lf]

Hi,

Here is shematics for analog out:

 

[@lf]

Here is shematics for modded analog out I found on the internet:

 

[@lf]

Here is another shematics for analog out:
I need opinion/explanation of this mods before I start desoldering.
Does anyone have any other suggestions for modding analog out?

I will post power supply shematics also.

 

[poynton]

Hi

Neither will work !

Andy

 

[@lf]

Hi

Neither will work !

Andy

There is mistake in first shematic. Here is correct one.

Any other who can comment these mods or have suggestion for different approach?

What about 14 220n caps on TDA1541A?

 

[@lf]

I removed 100uF cap and CDP has much more detail and better bass now.

 

[Bernhard]

You could try to remove the 2,2n slew rate limitation cap.
And the 22n cap on the output.

The first resistor with red X is for DAC current offset compensation, removing it will cause DC offset on output if 100µF is removed.
The middle part is the analog filter, gives lot of HF when removed because of 4x oversampling.

Try change the 14 decoupling caps for higher quality/value,
1k78 I/V resistor for better quality,
better op amps + better decoupling caps.

Upgrade to S1 chip + SAA7220B perhaps.

 

[@lf]

You could try to remove the 2,2n slew rate limitation cap.
And the 22n cap on the output.

Which one? (see red circles in shematic)

Try change the 14 decoupling caps for higher quality/value,

Higher value is =

I have at hand only 100n WIMA MKP


[/QUOTE]
1k78 I/V resistor for better quality,
better op amps + better decoupling caps.

Do you have any reccomendation (KIWAME, VISHAY)?

I have AD825 OP AMPS. Any other/better choice you can reccomend?

Upgrade to S1 chip + SAA7220B perhaps.
cap.

I have SAA7220B, S1 and S2 chip. I replaced TDA1541A with S1 (for S2 I'm not sure is it original or not) and player has more detail and better sound now.

THANK YOU for your replay 🙂

 

[@lf]

correct one

 

[Bernhard]

Which one?

The 2,2n below the I/V resistor.

Do you have any reccomendation (KIWAME, VISHAY)?

Maybe just make sure they are not magnetic.
Or Vishay ?

 

[@lf]

Thank you Bernhard!

Here is first part of PS shematic of my cd player.
What is the purpose of this four (circled in green) resistors?
What if I remove all of this four and bypass with wire?

What can be done here in order to improve power supply?
I replaced diodes with shottky 4A/100V.

 

[@lf]

here is second part of PS

 

[QSerraTico_Tico]

Which one? (see red circles in shematic)



Higher value is =

I have at hand only 100n WIMA MKP



1k78 I/V resistor for better quality,
better op amps + better decoupling caps.

Do you have any reccomendation (KIWAME, VISHAY)?

I have AD825 OP AMPS. Any other/better choice you can reccomend?



I have SAA7220B, S1 and S2 chip. I replaced TDA1541A with S1 (for S2 I'm not sure is it original or not) and player has more detail and better sound now.

THANK YOU for your replay 🙂

Allen Bradley CC and Russian Teflon (R) caps.

 

[Bernhard]

I am not sure, could be rc filter to filter out the last rail noise or overcurrent protection or both, you find those also on the op amps.

 

[QSerraTico_Tico]

Russian Teflons

Like these:
http://cgi.ebay.com/15-Teflon-Capac...yZ122649QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Make sure to wash off excess Pollonium!

 

[@lf]

Thank you for your info QSerraTico_Tico 🙂

 

[@lf]

I made NON OS mod but I found that sound become a little unplesant.

 

[poynton]

I tried today NON OS mod and I'm not pleased with the result.

in what way ?

 

[@lf]

But when I returned it in OS mode and soldered new caps (10.000 uF per rail) on PS - wow!!! more bass, more punch, more details!

 

[Bernhard]

I made NON OS mod but I found that sound become a little unplesant.

TDA1541A in non os becomes fat and sweet.