Not something that comes up that often, i know, but i do like my retro stuff and odd formats that never really took off.
Anyway, does anybody know of any mods that could be done to this unit like changing the op amps etc etc. I'm guessing there stands a good chance there wont be but unless i ask i wont ever know.
Thanks
Anyway, does anybody know of any mods that could be done to this unit like changing the op amps etc etc. I'm guessing there stands a good chance there wont be but unless i ask i wont ever know.
Thanks
Power supplies - Caps in the main PSU and also local decoupling caps. Most CDP upgrades are PSU related. Same principles certainly apply here. Have you got a Service Manual? Cant find schematics for this model on line. 😀
So you are saying that the local decoupling has been done incorrectly? Unless you understand the whole power delivery system of a design messing with local decoupling caps is the best idea...
Not incorrectly, no. Inadequately for satisfying sound most likely. Sufficient for delivering the specifications though, hence not incorrect.
Trying to find some pictures of the internals, the internet is a bit slow and restrictive so not having much luck at work!
Will try later when I can get to stuff... so cant comment specifically on this design.
Will try later when I can get to stuff... so cant comment specifically on this design.
Not sure if that comment is a "bait" or not but here goes......
Its a great idea 🙂. If you look and many designs, they use different types of caps and different values for the same pin on the same chip depending on where in the product line they came.
As a general rule, replacing an old elco on a digital rail with something like a oscon SEPC solid polymer type will help things.
Marantz and philips are the same. The KI marantz often use larger uF caps of certain types in the PSU. Local decoupling if often taken care of with the use of std caps in a base model and Elna Cerefine or Silmic in the more expensive ones. The circuit being identical except cap type and value across the range.
You asked for idea's for modification......these are normally the first place to start. Adding additional 0.1uf PPS caps als close to the supply pins on chips is another neat trick.
There are some basic rules of thumb that apply to most psu circuits.
Would be easy to make some suggestions with the circuit 🙂
I'm hoping to get Bikeral10 to give me a hand with any mods as i'm pretty much new to the whole modifying malarkey 😀
I do have the full service manual & schematics for the DCC-600. Its a large file as far as forums are concerned so i have uploaded it to a file share site.
I do have the full service manual & schematics for the DCC-600. Its a large file as far as forums are concerned so i have uploaded it to a file share site.
Code:
hXXp://www.filedropper.com/philips70dcc600+1 for replacing the caps. Not only do electrolytics age badly, but more often than not they will have been cheapies to begin with. Go with OS-CON or similar where you can. Also check the PCB solder pads on the big power supply components: age and weight stress can often put hairline cracks where the pad meets the PCB track: reflowing the solder on the pad tends to resolve this.
Following this: what do you want to upgrade - do you want better sound quality, louder, or more functionality? I developed some tiny DAC boards a couple of years back for upgrading old amps to take optical/SPDIF input. They work pretty well - got an old Denon sitting here who's tape input has been diverted to an optical input from my AppleTV.
Following this: what do you want to upgrade - do you want better sound quality, louder, or more functionality? I developed some tiny DAC boards a couple of years back for upgrading old amps to take optical/SPDIF input. They work pretty well - got an old Denon sitting here who's tape input has been diverted to an optical input from my AppleTV.
Looking at the manual......
PSU board
Caps 2215, 2216, 2217 replace with same voltage larger uF caps. These are the PSU reservoir caps. Prob replace 2211 2213 with same value uF.
Probably limited by physical size here. Something like Panasonic FR or FC or TSUP if they fit.
Digital board
On the digital board, replace all the elcos with OsCon SEPC solid polymer much higher uF like 470uf 6.3v unless they are doing a specific job other than PSU. Check with the manual.
Analogue output stage
2257, 2258 2259 2260 are elco's in the signal path - replace with 4.7uf film caps like WIMA MKS2 (tiny with 5mm lead spacing) and very good.
Opamp 7305 replace with dual opamp of choice (LME49720 is my choice) and see if you can get some local elco's on the PSU pins
2351 & 2352 in the feedback loop with 470 pf Silver mica
Obviously do a bit at a time and listen in between........
These mods are suggested based on general experience modifying similar equipment and not the DCC600 directly......
Good luck!!! 😀
PSU board
Caps 2215, 2216, 2217 replace with same voltage larger uF caps. These are the PSU reservoir caps. Prob replace 2211 2213 with same value uF.
Probably limited by physical size here. Something like Panasonic FR or FC or TSUP if they fit.
Digital board
On the digital board, replace all the elcos with OsCon SEPC solid polymer much higher uF like 470uf 6.3v unless they are doing a specific job other than PSU. Check with the manual.
Analogue output stage
2257, 2258 2259 2260 are elco's in the signal path - replace with 4.7uf film caps like WIMA MKS2 (tiny with 5mm lead spacing) and very good.
Opamp 7305 replace with dual opamp of choice (LME49720 is my choice) and see if you can get some local elco's on the PSU pins
2351 & 2352 in the feedback loop with 470 pf Silver mica
Obviously do a bit at a time and listen in between........
These mods are suggested based on general experience modifying similar equipment and not the DCC600 directly......
Good luck!!! 😀
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BTW, clock looks horrid!!! Lots of cascading via multiple chips!!
If you must, you could see what replacing the 24.576mhz clock does on the Sa2021 sub band decoder. The clock is then redistributed via multiple other chips and logic!
If you must, you could see what replacing the 24.576mhz clock does on the Sa2021 sub band decoder. The clock is then redistributed via multiple other chips and logic!
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