Marantz CD63 & CD67 mods list

[6h5c]

Originally Posted by Stabby

DAC:
- Removed CD04, CD07 and CD15/16 (no replacement, no bypass)

This line bothers me a bit. If you only removed these caps and didn't put anything back, that means the DAC doesn't have any local decoupling. That's not good. You should really insert some decent caps there!

I know in my mods list it says 'remove' at these caps, but then you're only doing half the job. You are supposed to add the new caps at CD05, 06, 12 and 13, with the original 100n decoupling added at the back of the board. The point is that these positions are closer to the DAC-chip, so they give better decoupling.

Ray

[Ben Hanke]

Hey guys, I'm plucking up the courage to have another go at fitting regs to my DAC's digital supply. I've refined my implementation of Martin's 'simple but good' 5v reg, this time with solid tantalum caps. It didn't work out last time, so I want to double check with you guys first.

As far as I understand it, I can remove RD01 and RD04 and connect the 5v supply there. I'm OK with that part... but I'm still not 100% about the other pins. Can someone please advise me?

Where's the best place to wire the regs to ground if I'm leaving CD04/CD07 in place? Should they both go as close to the ground pin of the chip as possible?

Also, where's the best place to take the input from? (I was thinking C813).

Thanks in advance,

Ben

[UV101]

Originally Posted by Stabby

I have only been able to try to connect my CD player to the AUX input of an old Technics amp. This amp works fine with my record player, no lack of bass on my records. I then did the same as I do with my record player: I use the tape output and connect it to the inputs of my mixer. Bass is still the same, no improvement at all.

I'm not following you? so did the bass improve when using the CD directly into this amp? I'm surprised that AUX works for a TT, but thats not the issue here!

Originally Posted by Stabby

DAC:
- Removed CD04, CD07 and CD15/16 (no replacement, no bypass)
- Replaced C605/606 with 470pf
- Replaced R605/606 and R611/612 with 12k
- None of the other existing mods in this section

So what local decopling do you have on the DAC?

I'm not sure it says anywhere to remove those 4 elco's and replace with nothing!
CD15&16 are local decoupling for the DAC analogue rails
CD07 is the local decoupling for the DAC digital rail
CD04 is the local decoupling for the DAC clock rail (also digital)

The analogue rails need to be something like Rubycon ZA or ZLG at 220uF or 470uF and the digital rails should be Oscon SEPC 470uF. (Caps are very much a personal thing but this is what I would use 2nd only to Black Gates on the Analogue rails)

PM Thomo on this thread he should be able to do a set for about £11 plus postage.

Whatever you do, you NEED these caps. They may or may not be the total cause of the problem but without them you are very likely to have seriously downgraded the audio quality by some margin!!!

[UV101]

Originally Posted by 6h5c

This line bothers me a bit. If you only removed these caps and didn't put anything back, that means the DAC doesn't have any local decoupling. That's not good. You should really insert some decent caps there!

I know in my mods list it says 'remove' at these caps, but then you're only doing half the job. You are supposed to add the new caps at CD05, 06, 12 and 13, with the original 100n decoupling added at the back of the board. The point is that these positions are closer to the DAC-chip, so they give better decoupling.

Ray

LMAO!!! you beat me this time Ray!!! I was too slow typing my reply!!!

[Stabby]

Originally Posted by 6h5c

This line bothers me a bit. If you only removed these caps and didn't put anything back, that means the DAC doesn't have any local decoupling. That's not good. You should really insert some decent caps there!

I know in my mods list it says 'remove' at these caps, but then you're only doing half the job. You are supposed to add the new caps at CD05, 06, 12 and 13, with the original 100n decoupling added at the back of the board. The point is that these positions are closer to the DAC-chip, so they give better decoupling.

Ray

I removed those caps a long time ago, so is it possible I have caused permanent damage to the DAC? Does this explain the huge lack of bass or is this a different problem?

With the 100n caps, do you refer to the ones I removed or CD05/06/12/13? Also, I don't know where exactly these should go.

Thanks for the help and sorry for asking way too many questions...

Originally Posted by UV101

I'm not following you? so did the bass improve when using the CD directly into this amp? I'm surprised that AUX works for a TT, but thats not the issue here!

Using the amp did not result in any improvements.

[Ben Hanke]

I've tried a few different kinds of cap on CD15/16 and I found they have a massive influence on the sound quality.

[6h5c]

Originally Posted by Ben Hanke

Hey guys, I'm plucking up the courage to have another go at fitting regs to my DAC's digital supply. I've refined my implementation of Martin's 'simple but good' 5v reg, this time with solid tantalum caps. It didn't work out last time, so I want to double check with you guys first.

As far as I understand it, I can remove RD01 and RD04 and connect the 5v supply there. I'm OK with that part... but I'm still not 100% about the other pins. Can someone please advise me?

Where's the best place to wire the regs to ground if I'm leaving CD04/CD07 in place? Should they both go as close to the ground pin of the chip as possible?

Also, where's the best place to take the input from? (I was thinking C813).

Thanks in advance,

Ben

RD01 and RD04 are o.k., the other pins are 17, 21, 22 and 26. You can separate them from the supply by removing RD17 and RD18, which are wire-bridges and are not documented in the schematic.

The ground is indeed best connected close to the appropriate ground-pin of the DAC. This can be tricky because the wiring then has to go under the board, and long wire lengths are not good. So the next best solution is to solder the ground of the reg to the top ground-plane. But if CD05 and CD06 are moved to the back of the board, you could also use these empty holes to connect the grounds.

C813 is the right place for taking digital supply.

Ray

[6h5c]

Originally Posted by UV101

LMAO!!! you beat me this time Ray!!! I was too slow typing my reply!!!

Sloooooooow woman!

[UV101]

Originally Posted by Stabby

I removed those caps a long time ago, so is it possible I have caused permanent damage to the DAC? Does this explain the huge lack of bass or is this a different problem?

With the 100n caps, do you refer to the ones I removed or CD05/06/12/13? Also, I don't know where exactly these should go.

Thanks for the help and sorry for asking way too many questions...




Using the amp did not result in any improvements.

The 100n are the little blob caps or ceramic (cant remember) these are CD5,6,12 & 13. The reason you remove these to to put the larger elco caps CD4,7,15 &15 in the holes left by the 100n. The is to get the new caps as close to the pin of the DAC chip as possible. You can then use X7R 100n caps directly on the pins of the dac if you want (google accoustica cd63 clock hack). Make sure you observe polarity with the elcos' It doesnt matter with the 100n caps.
You shouldn't have damaged the dac running without local decoupling but you will be making a horrid sound from it!! Anything will be better than nothing.

Originally Posted by 6h5c

Sloooooooow woman!

now now Ray

[6h5c]

Originally Posted by Stabby

I removed those caps a long time ago, so is it possible I have caused permanent damage to the DAC? Does this explain the huge lack of bass or is this a different problem?

With the 100n caps, do you refer to the ones I removed or CD05/06/12/13? Also, I don't know where exactly these should go.

I don't think there will be any damage. Everything is still working, right?

Just follow the mods list. For example, CD04 and CD05 are on the same supply-pin, look at the schematic! CD04 is removed, and CD05 is a small 47n ceramic cap originally. The new electrolytic is now place at CD05 instead of CD04 (closed to the IC), and the extra decoupling which used to be CD05 is now soldered at the back of the board, between the pins of the new cap at CD05.

Ray