NAD C521BEE mods - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 22nd March 2009, 03:09 PM   #1
udovdh is offline udovdh  Netherlands
diyAudio Member
Join Date: Jan 2009
Default NAD C521BEE mods


I am thinking about putting a DEXA/NewClassD clock in my C521BEE.
Where would I get the 9V power for this clock from?
At the input of the 7808 that I can see in the C521 (not BEE) datasheet?
(Anybody who has a C521BEE datasheet who can advise me?)
This is a regulator for digital power, I do not want to use analog power supplies for fear of polluting the power.

Is the C521BEE schematic very similar to the C521 one?

Also, while the player is opened, what other quick mods are in place?
The capacitors near the opamps? (Yes, I do use a Zhaolu D2.5C DAC but any improvement is welcome)
Anything else which can help significantly?

Please post!

  Reply With Quote
Old 22nd March 2009, 08:59 PM   #2
udovdh is offline udovdh  Netherlands
diyAudio Member
Join Date: Jan 2009
Also: how is the DAC chip clock tied to the S/PDIF clocking?
  Reply With Quote
Old 23rd March 2009, 03:43 PM   #3
udovdh is offline udovdh  Netherlands
diyAudio Member
Join Date: Jan 2009
So a D-clock (Dexa) should be in the mail.

Power to be taken from the input of the 7808.
Rest of assembly:
Remove the 2 capacitors and the old xtal.
Connect the clock wire screen to near by GND, and the inner
conductor to pin 5 if PCM1710. Careful, this chip is a bit
sensitive to static electricity.

(Straight from Claus)

(assuming the C521BEE is similar to C521 in digital design)

What about the quick analog tweaks?
Are capacitor values same as in C521 for BEE version for the opamp capacitors?
  Reply With Quote
Old 23rd March 2009, 07:17 PM   #4
udovdh is offline udovdh  Netherlands
diyAudio Member
Join Date: Jan 2009
On the C521 schematic that I have (not for BEE) I see small markings near the IC pins like 0V, 5V, 2.3V etc.
Are these indeed voltage indications?
How should I interpret the markings of 2.3V near the pins where the crystal is connected?
The D-clock does 3.3 and 5V. Which mode should I use in this case? (CD-players mostly do 5V and there is no 3.3V supply in the C521...)
Who can explain?
  Reply With Quote
Old 3rd April 2009, 02:31 PM   #5
udovdh is offline udovdh  Netherlands
diyAudio Member
Join Date: Jan 2009
I just did it.
The D-clock is in the C521BEE. I set it for 5V. Works OK.

The power wire is a bit short.
I attached it to the bottom of the board at U504 and ran it to the top of the board via the backside of the case.
At the PCM1710 location I removed the crystal and dual capacitors.
I soldered two pins through the board connecting to GND and pin 5 of the DAC chip using the remaining holes.
At the top of the board I connected the coax to these pins.

I used a standoff from a PC case in the hole near M320 to fasten the D-clock.
The other end rests over RL101.
  Reply With Quote
Old 3rd April 2009, 03:02 PM   #6
udovdh is offline udovdh  Netherlands
diyAudio Member
Join Date: Jan 2009
BTW: Anybody know a reliable S/PDIF coaxial switchbox with about 4 inputs that works at 192/24?
  Reply With Quote
Old 6th April 2011, 11:10 AM   #7
diyAudio Member
littleant's Avatar
Join Date: Apr 2011
Location: Tartu
Default Replace C521BEE display with C542s display

Is it possible to replace C521BEE display with C542s display?
I have C521BEE and C425 Tuner. I like C425 fluorescent display and C542 has also fluorescent display which seems to have identical data with C521BEE.

And if it is possible then is it possible to get C542s display (with reasonable price)? Maybe someone has broken C542 which display still works.
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
NAD C521BEE service manual needed udovdh Digital Source 3 6th May 2009 08:05 AM
Tweaking My NAD C521BEE CDP Dino-Indo Digital Source 0 16th August 2007 05:39 PM
NAD C521BEE mods Roeland Digital Source 4 28th October 2006 07:32 AM
ns-10 mods nvinyl66 Pass Labs 42 17th February 2006 01:21 PM
What are Mods? pinkmouse Everything Else 4 4th November 2004 12:33 PM

New To Site? Need Help?

All times are GMT. The time now is 09:36 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2