Well known fact - something you've done yourself always sounds better than something someone else did (even if it doesn't!)
True enough! It's not really finished as long as you can see the board! I seem to remember I asked Brent about the CTP mod but he was non-commital at the time. I presume this is the add-on to the DOS board? I'm like a parrot: I can use the words without knowing what I'm saying! Well at least I figured out how to up-load photos all on my own!
Yep! If you lower them a bit, the output will be higher and vice versa. But don't make it too small or the signal will clip eventually.
That will probably be the flatcable between the front panel and the main PCB. They fail pretty quickly because they are not made to be inserted so many times.
Nice pics Shep!
Ray
CFP mod for the DOS
Now that you know, you msut do it, all of you guys.
Ray did yours improved as much as it did on my player? Or the super regs were also needed? I feel like the only one to find that to be terrific...
Now that you know, you msut do it, all of you guys.
Ray did yours improved as much as it did on my player? Or the super regs were also needed? I feel like the only one to find that to be terrific...
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Wohow!!! The Marantz is alive again!! And how
Replaced the big caps:
C815 Rubycon ZL 6800UF, 6.3V -> 4700UF Elna simnic (left over from C813)
C805/806 Panasonic FM 2200UF, 16V -> Panasonic 1000UF, 63V TSUP (no more new caps for the Rotel amp...)
That brings back the music! Much more details and depth.
Then I tried the "drivers regs mod for beginners" (and some copper foil to the chips): whooooow!! Had to fit the regs under de pcb because of the big 22000uf caps :-(
Hope that's not gonna give problems, or should I drill a hole in the bottom plate to give it some ventilation?
Tnks guys for helping me out here! I'm so happy. You are great!!
Replaced the big caps:
C815 Rubycon ZL 6800UF, 6.3V -> 4700UF Elna simnic (left over from C813)
C805/806 Panasonic FM 2200UF, 16V -> Panasonic 1000UF, 63V TSUP (no more new caps for the Rotel amp...)
That brings back the music! Much more details and depth.
Then I tried the "drivers regs mod for beginners" (and some copper foil to the chips): whooooow!! Had to fit the regs under de pcb because of the big 22000uf caps :-(
Hope that's not gonna give problems, or should I drill a hole in the bottom plate to give it some ventilation?
Tnks guys for helping me out here! I'm so happy. You are great!!
Thanks Ray. More to come. I'm gluing the last piece of lead to the bottom as we speak.
The wood needed a tiny bit of adjustment. Done. What's the CTP mod? I forgot
It's CFP-DOS. CFP stands for Complementary Feedback Pair. It's an improvement of the DOS' input stage. You can find the schematic on the page Matthieu linked to. Info is a bit limited there, but i'm planning to expand it soon, with more pictures and stuff.
Yes, the CFP-mod is a very worthwhile improvement to the DOS. I upgraded the DOS in my SA8400 a while ago as you may recall, and the change in sound is quite noticeable now that it has played a few weeks! Here are some more pictures.
Ray
Attachments
I believe I fitted a 7805 and SEPC Oscon to isolate it. I also run the RF down a coax so that it does not get any pickup from the uP
Brent
An externally hosted image should be here but it was not working when we last tested it.
Look what I found
Think I'll have a proper go at this as my new project. I've tried lots of different players and dacs etc over the last couple of years and none of them have been capable of the dynamics, detail and just downright brilliant sound of a fully modded cd63.
I'll be doing this pretty slowly fitting it in around work. I'll do my best to document as much of it as possible on here as it could help a few of the newcomers to this thread.
Long may it continue,
Lee.
