I just design it on paper 
Thomo said:
I would suggest the free version of Eagle or kicad. Having said that, I use the free software from ExpressPCB - which is pretty good - but doesn't allow you to make gerber files. That is something I wish I had realized in advance of designing the ezDAC. On the plus side, I'm pretty happy with the boards they produce, so I don't have a real good reason to switch.
rowemeister said:
Thanks, for posting these Brent. This gives me an opportunity to remind folks that what may look like solder bridges are actually due to the short traces that connect some of the pins together on each chip. People should make sure they know which these are, otherwise, frustration with the excessive use of solder wick may ensue.
Also, although Brent knows what he's doing, I suggest in the ezDAC construction guide that some of the smt components (C36, C37, C31, R36) seen in Brent's pics be soldered before the chips. Soldering these components first should be easier than doing the chips first, and shouldn't affect soldering the chips, because they are not adjacent to the IC pins. This suggestion comes from my own experience, feeling "trapped" by having done the chips first.
One last thing...(as Steve Jobs like to say)...I think all these ezDAC posts are a little off topic for this thread. Since many of you guys are now working on it, maybe you should start posting in the ezDAC thread that already exists here:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=87873
rowemeister said:
Thank you Lee and Brent.
I will order four inittially.
Before I swap the opamps I think I need to implement the regulators. I believe I can put up something based on the LM317 and LM337, but need some help.
The layout I saw, has only fixed resistors and some caps. As the regulators are not fixed voltage ones as 78 / 79, what should be the perfect values of the resistors ? What happens if the Tx does not exactly output +-18V ? Can I use a TX of +-20V ?
Best Regards
Ricardo
Re: Capacitor Multiplier
Thank you Andy
So in the Super Raygulator, the BC547 / BC557 layout acts as a Capacitance Multiplier.
The 4.7uF are multiplied several times by the circuit..?!
Nevertheless, I still do not know if this circuit depends or not of the TX output to provide +-12V.
Does the output voltage of the TX matter ?
Thank you for the support.
My CD is starting to sing......
poynton said:
Thank you Andy
So in the Super Raygulator, the BC547 / BC557 layout acts as a Capacitance Multiplier.
The 4.7uF are multiplied several times by the circuit..?!
Nevertheless, I still do not know if this circuit depends or not of the TX output to provide +-12V.
Does the output voltage of the TX matter ?
Thank you for the support.
My CD is starting to sing......
6h5c said:After modding a Marantz CD63 and a CD67OSE I decided to make a list of all the various mod's I found here and elsewhere on the internet.
I'd like to donate my files to this forum, for all to enjoy!
Of course I do not pretend this list to be complete.
This is all I've done to the players so far and more good tips are welcome!
Greetings,
Ray.
Hi Ray
I am finally starting to upgrade the analog output of the CD 53.
Inittially, I will be using the stock TX and intend to replace the 78 / 79 regulators by the LM317 / LM337, following your schematics.
Can you please advise on the pcb pins you are using ? Can I get all the parts from Farnell ?
If this goes allright I will try the Super-Raygulator... for now I am not at ease with the layout.
Regards
Ricardo
SimontY said:
Hi,
My experience,
When I blew my modded CD67 I bought a Cambridge 640c v2 to tide me over while I waited for a suitable replacement off Ebay.
Brand-new, out of the box the 640 sounded stuinning for a £250 player. Much better than I remember the basic KI-S sounding.
Anyway, I rebuilt the 67 with all the mods from my blown machine and it sounded slightly better than the unmodded 640. Similar lever of detail but the 67 just sounded nicer! Not a lot in it though.
So I modded the 640 audio board:
Swapped the 6 opamps for 4 * LM4562 and 2 * AD827 (should be all LM4562 but I blew one!)
Swapped the 5v dac regs and +/- 15v opamp regs from 78/79 to raygulators.
Swapped the main ecs to Pana FC
Swapped the reg decoupling to Rubycon ZAs
Removed the DC blocking caps.
Now it sounds pretty stunning, much more detail than the 67 and a nice easy to listen to sound as well. I only got it all working yesterday so nothings run in yet but I spent the afternoon listening to cds with a big fat grin on my face!
Next steps are the additional LM4562s, super-reg for the clock and seperate PSUs for the clock and dacs.
Regards
Pete
SimontY said:Pete,
That's really interesting! It's as I suspected tooOlder players will need more more mods to compete.
Simon
I think the cambridge is a pretty well designed machine to start with, (reportedly) very low jitter clock, twin dacs, 2 seperate regs for each dac, seperate reg for clock. Really, just let down by some cheap components. I'm sure there are other modern machines around which would require an awful lot more work.
BTW, audiocom now offer a mod package for the 640 at £250.
Regards
Pete