Marantz CD63 & CD67 mods list

Btw, IMHO the www.acoustica.org.uk clock mod is sufficient.
I later added a LCclock with separate PSU...not worth the £££. Maybe the LC units have improved since then...?
With all the mods I made, the CD63 got close to a stock Quad 67 or 99CDP, but with an "unbalanced" and "wild" sound, definitely not bad.
I prefer the Quad, though, although I had fun modding my CD63s, learnt a lot from it and all you nice guys here and at audio asylum.

My top 5:
1. Fill it with bitumen and tack-it
2. Remove/short the output caps
3. the 10k/27k (and better 120p caps) match
4. clean up the 5V rail
5. acoustica clock mod
(in order of difficulty)

Maybe using coax for the digital signal transfer to the DAC in the CD67 also is worthwhile, on the CD63 it doesn't travel around the globe to pick up noise.
 
jksmurf said:
Thanks Simon, (please pardon my ignorance) presumably "decoupling is what was meant by "Using a set of 4# 3.6kOhm resistors....

Hi,

Actually what I meant was power supply decoupling. That is to solder a capacitor from each supply pin to ground (close to the circuit you're feeding). This removes noise. This can be considered optional if you have really good caps close by on the circuit (according to Rowemeister).


mods generally. Thanks you very much for your list. Now I just have to look at rays service manual and point out where everything goes....

There seems to be a plethora of clocks... Kwak 7 (DIY), Tent XO, LCClock XO, Superclock ... What's the easiest install / good value assuming my wife can make the Kwak?

You're quite welcome. As I've personally only tried one add-on clock I can't comment on how good each one is. You'll need to do some searching around for that. Some people have compared several.


Mine's a 67SE, presumably all 10 still apply?

Nope, one of them doesn't. The clock divider circuit to feed the servo chip is not needed in the CD67. Because the CD67 has fewer parts, when you reclock the DAC you also reclock the servo automatically. So you should really feel the benefits of a good clock instantly (space, texture, timing, bass, quality top end etc etc.)


Robfow said:
Hi Guys, I will have some spare time in the next couple of weeks. I am thinking of finally replacing the opamps in my CD63. I have read through the pages here but am still a little lost. I might have missed out some information somewhere. I have some OPA124 to use also, I've read that this can be used after the DAC?

a) If I were to use opa627, I need 2 of these to replace each 2114?

b) If I use the LM4562 then it is just a direct replacement for the 2114?

Thank you in advance :)

Hi,

To use OPA627 you need two chips as they only come as single op-amps. You also need an adaptor board. Search for Brown Dog.

LM4562 drops straight in and is excellent.


Zombie said:
:smash: Just can't emphasise enough that perfect matching of the 10k and 27k resistors afte the DAC is necessary to reap full benefits of what is done in the analogue circuit. What's even better, it might be for free!

Cheap alternative: locate other 10/27k resistors on the board (headphone amp), desolder, match within 0.1% (or better) and solder back those that didn't match in the other locations.

Expensive alternative: buy a lot of 1% 10k/27k resistors, or even better, match them in the shop, or buy the right amount of resistors with 0.1% tolerance. The better the match, the better the result!

After you've matched, THEN you start can talking opamps, caps, shottkys, clock mods, separate regulators, etc etc :smash:
(IMHO better opamps just let you hear all the crap that comes out of the DAC much better)

To be honest, as much as I don't doubt what you're saying, it just doesn't reflect my own experience of changing these resistors. I did it some time ago, using 1% metal films matched to 0.1% with a DMM, and the sound actually got worse. It became overly dry and bland. I blame it on the metal film resistors, but the matching can't be all that important for sonics if it gets worse. Maybe my system and player at the time were not good enough to reflect the superior sound. I'm open to suggestions.

I'm getting a discrete output sorted soon anyway. Having heard Brent's player back to back with mine I know that would be a smart move! (also needs more psu work of course, which I'm currently working on...)

Regards
Simon
 
Hi guys,
for the CD53 onwer I am, what is to be done with the R619 R620 ( Factory bypass of the HDAM ), I read 10 ohms on my meters ( no K or anything, just 10 ).
I've all the resistors of Ray's list, which seems to be 10K or 27K and 10.
Guys with le LM4562, what have you done about decoupling? Seems avr300 nothing (but cap on the AD8620), Symonty 2 caps per opamps? Whatever, I can already fit them on the board ;)
What is to be used for linking the new gold RCA and the PCB, any big copper cable as main power wire?

Thanks, soon the Ray's enhanced PCB is done, I'll show you very soon :)
Thanks to all!!
 
Zombie said:
Btw, IMHO the www.acoustica.org.uk clock mod is sufficient.
I later added a LCclock with separate PSU...not worth the £££. ....

A new clock with exclusive PSU is too expensive for the upgrade, fully agree with that. A much better bang for the buck is puttin in new decent caps. If you haven't bought caps, try those Panasonic audiograde (blue jackets), very nice.
Jaap
 
Originally posted by disco A new clock with exclusive PSU is too expensive for the upgrade, fully agree with that.
Do I understand it correctly that the FLEA with e.g. the TENT XO Oscillator on board is a considerably cheaper clock replacement than a commercial clock (but perhaps not a Kwak Clock)? So then the cost is reduced except of course for the seperate PSU?

k.
 
Malefoda said:
what have you done about decoupling? Seems avr300 nothing (but cap on the AD8620), Symonty 2 caps per opamps?

Hi, I have left the 2 x 33uF/50v Pana FC in place under the op-amp sockets. I don't intend to experiment further in this area.

Here's a sneaky peek at what I'm doing for my cd player now...

The first of a potential gaggle of transformers. Each winding will feed a bridge made with schottky diodes, then a 1000uF Nichicon Muse cap for smoothing. The +21 volts will then go via an umbelical cord to the player, where it will meet a further 1000uF, an audiocom super regulator, then a quality cap and feed the clock and servo clock divider. There's a little mains filtering there by the power inlet.

Next could be a transformer for the digital parts of the DAC and decoder... I'm quite excited about this box as I can put all sorts of stuff inside that won't fit under the hood of the cd63 :D
 

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SimontY said:


Hi, I have left the 2 x 33uF/50v Pana FC in place under the op-amp sockets. I don't intend to experiment further in this area.

Here's a sneaky peek at what I'm doing for my cd player now...

The first of a potential gaggle of transformers. Each winding will feed a bridge made with schottky diodes, then a 1000uF Nichicon Muse cap for smoothing. The +21 volts will then go via an umbelical cord to the player, where it will meet a further 1000uF, an audiocom super regulator, then a quality cap and feed the clock and servo clock divider. There's a little mains filtering there by the power inlet.

Next could be a transformer for the digital parts of the DAC and decoder... I'm quite excited about this box as I can put all sorts of stuff inside that won't fit under the hood of the cd63 :D

I look forward to the end result ;)

Brent
 
6h5c said:
..... I want to do a comparison between the players I have, and in one of them I want to bias the opamps in class-A. But if you want to try it yourself, it's a 5 minute mod. Just solder a resistor between each output and the negative voltage rail. Somewhere between 3k3 and 3k9 for +/-12V supply. That should give you a pretty good idea of the change in sound. If you like it you can change the resistor into a more sophisticated FET current sink.
Regards, Ray

Originally posted by SimontY
It may be important to add power supply decoupling right under the pins (of the socket - use a socket so you can compare op-amps easily). I use Panasonic FC 33uF/50v and they work well. These go from + to earth and - to earth. I think + and - are pins 4 and 8 on the op-amps. Simon

OK, so there's (i) "biasing the opamps in class-A" and (ii) "power supply decoupling" ... how many have done (i), (ii) or both and what are your experiences?

Cheers

k.
 
jksmurf said:
OK, so there's (i) "biasing the opamps in class-A" and (ii) "power supply decoupling" ... how many have done (i), (ii) or both and what are your experiences?

Cheers

k.

Not biased any opamps into class a. Mainly becuase many people have said it's not worth it/doesn't get better.

I have listened before and after psu bypassing done under the op-amp socket legs. Listening to the op-amp both ways (OPA2134) the difference was very useful extra control and involvement. The sound got tighter. This was using small, low impedance electrolytics.

I don't doubt the improvements will be greater or lesser depending on the quality of the caps used to bypass, the other caps used, their proximity to the op-amps and also the type of op-amp. Search for posts by the user CarlosFM (I think that's the one) as he's tested many capacitor and op-amp combinations.

Regards,
Simon
 
SimontY said:


Not biased any opamps into class a. Mainly becuase many people have said it's not worth it/doesn't get better.



Hi.

The reviews I have read state that biasing into class A makes a subtle but noticable difference.
I suppose it does depend on how modified your CDP is and also the type of opamp being used.

Class A generally gives a more musical sound as the distortion components are even harmonic as opposed to odd harmonics from class B (unless it is driven to clipping).

Having said that, Ray's discrete FET output is class A and would seem the route to go for the 'ultimate' uotput stage.

Andy