What ! 😱 Ridiculously ? 
It's full of usefull info 😀 And only +6800 posts. Easy reading.
I have the 950 running here with AD8599. The next move is a Flea.
It's full of usefull info 😀 And only +6800 posts. Easy reading.
I have the 950 running here with AD8599. The next move is a Flea.
Thanks Phil and AVR.
Easy Reading Huh? It's so easy, that it plays like a never ending movie in my head in my dreams of some low budget Horror Flick! At least there aren't any commercials! (just kidding but it does remind me of Frankenstein, parts from all over the place, some dead to build I don't know what). And this is what I want to do for fun? Maybe I should change the Horror Flick to "One Flew Over The Cuckoo's Nest".
You gotta love it!
Regardfs//Keith
Easy Reading Huh? It's so easy, that it plays like a never ending movie in my head in my dreams of some low budget Horror Flick! At least there aren't any commercials! (just kidding but it does remind me of Frankenstein, parts from all over the place, some dead to build I don't know what). And this is what I want to do for fun? Maybe I should change the Horror Flick to "One Flew Over The Cuckoo's Nest".
You gotta love it!
Regardfs//Keith
I totally agree that its easy to lose your way in there🙂
But, there are a LOT of useful mods in there, which should be applicable to other players.
Anyway, I modded my CD63 a few years back, and the most obvious, easy, value for money mods to make from a fresh CDP are probably:
Upgrading output opamps.
Adding a clock module.
Removing output muting transistors.
Improving power supplies (upgrading electrolytic decoupling caps, replacing series safety resistors (if present) with inductors).
Replacing output filter components with higher grade components (can be quite expensive, so I wouldn't advise doing that immediately).
Mechanical damping (bitumen 'dead sheets', acrylic caulking etc).
Beyond that, you might have to start searching/trawling through the CD63 thread.
Cheers,
Phil
But, there are a LOT of useful mods in there, which should be applicable to other players.
Anyway, I modded my CD63 a few years back, and the most obvious, easy, value for money mods to make from a fresh CDP are probably:
Upgrading output opamps.
Adding a clock module.
Removing output muting transistors.
Improving power supplies (upgrading electrolytic decoupling caps, replacing series safety resistors (if present) with inductors).
Replacing output filter components with higher grade components (can be quite expensive, so I wouldn't advise doing that immediately).
Mechanical damping (bitumen 'dead sheets', acrylic caulking etc).
Beyond that, you might have to start searching/trawling through the CD63 thread.
Cheers,
Phil
Thanks Phil,
First,I am taking my Rotel down that path in a slightly different order, then the Philips.
I already had a new DAC installed at Rotel and the Transport serviced while there. I didn't know how to diagnose a fried DAC other than bad distortion and that could be many things. Plus this DAC is very delicate and I am a beginner. I would trash it, better to let them do that. So I am doing the following.
Op amps first (OPA627AP). Then figure the best way to bias them to Class A. I can use a resistor between pins but it doesn't stay Class A under load. I need to find the best circuit to maintain Class A throughout the range of the load.
Muting Transistors (Swapped out for better) Relay circuit is next after I figure out how to design and implement one.
Clean up the Power is next and make it as clean as possible, including an IEC inlet, better Power Cord and internal wiring to the power block.
Then the clock and maybe its own PS. (Also have to figure out which)
Dampening. We have an excellent product here in the US called "Dynamat Extreme" used in the automotive industry that is perfect for this.
Then finally maybe trying to find some BG caps and other quality components to take it to the limit. When I get to this point I will also replace some internal wiring with silver plater copper cryo wire and better RCA outlets.
I like the way you think!!!!
Regards//Keith
First,I am taking my Rotel down that path in a slightly different order, then the Philips.
I already had a new DAC installed at Rotel and the Transport serviced while there. I didn't know how to diagnose a fried DAC other than bad distortion and that could be many things. Plus this DAC is very delicate and I am a beginner. I would trash it, better to let them do that. So I am doing the following.
Op amps first (OPA627AP). Then figure the best way to bias them to Class A. I can use a resistor between pins but it doesn't stay Class A under load. I need to find the best circuit to maintain Class A throughout the range of the load.
Muting Transistors (Swapped out for better) Relay circuit is next after I figure out how to design and implement one.
Clean up the Power is next and make it as clean as possible, including an IEC inlet, better Power Cord and internal wiring to the power block.
Then the clock and maybe its own PS. (Also have to figure out which)
Dampening. We have an excellent product here in the US called "Dynamat Extreme" used in the automotive industry that is perfect for this.
Then finally maybe trying to find some BG caps and other quality components to take it to the limit. When I get to this point I will also replace some internal wiring with silver plater copper cryo wire and better RCA outlets.
I like the way you think!!!!
Regards//Keith
Hi
Firt I'm most interesting to mod existing PS and add dedicated PSU for DAC. I think to add external big PSU +-18V and +-12V to avoid trafos in case of CD (like in Naim CD)
If anyone built add PSU for the CD950?
JKoch
Firt I'm most interesting to mod existing PS and add dedicated PSU for DAC. I think to add external big PSU +-18V and +-12V to avoid trafos in case of CD (like in Naim CD)
If anyone built add PSU for the CD950?
JKoch
Hi,
Keith, I get the impression you're replacing the muting transistors? I think its best to whip them out completely. You'll get some noise switching the thing on or off, just don;t do it with the amplifier on. Then one day go for relays if you must (I've never bothered).
I'd do a search for different op amps, there are loads out there, and you can have fun comparing them. LM4562 are all the rage at the moment (and are very good, although I prefer LM6172 for my TDA1541 IV stage). Although the 627s are very good, they're also expensive
JKoch,
In my CD940 (which I stripped down to make a transport), I did add a PSU for my Kwak Clock. It was fairly simple to do. All internal though.
Cheers,
Phil
Keith, I get the impression you're replacing the muting transistors? I think its best to whip them out completely. You'll get some noise switching the thing on or off, just don;t do it with the amplifier on. Then one day go for relays if you must (I've never bothered).
I'd do a search for different op amps, there are loads out there, and you can have fun comparing them. LM4562 are all the rage at the moment (and are very good, although I prefer LM6172 for my TDA1541 IV stage). Although the 627s are very good, they're also expensive
JKoch,
In my CD940 (which I stripped down to make a transport), I did add a PSU for my Kwak Clock. It was fairly simple to do. All internal though.
Cheers,
Phil
Attachments
Also,
I never got round to biasing opamps into class A (I still aim to use a discrete IV converter 🙂 ), but you can use a current source to do the biasing. I believe it can be done with a FET and a resistor, that would be the simplest way to do it, other than a resistor.
Again, a search should put you in the right direction.
On my CD63, I always put it off as I didn't think it would an easy mod to do first. However, I've heard others claim it made a big difference.
Before biasing the opamps, I'd seperate out all the power rails and feed them with seperate regulators. Even using simple 78xx regulators made a big difference.
Thankfully I don't need to do that so much on mine, because its only powering the decoder, servo and CPU 🙂.
Cheers,
Phil
I never got round to biasing opamps into class A (I still aim to use a discrete IV converter 🙂 ), but you can use a current source to do the biasing. I believe it can be done with a FET and a resistor, that would be the simplest way to do it, other than a resistor.
Again, a search should put you in the right direction.
On my CD63, I always put it off as I didn't think it would an easy mod to do first. However, I've heard others claim it made a big difference.
Before biasing the opamps, I'd seperate out all the power rails and feed them with seperate regulators. Even using simple 78xx regulators made a big difference.
Thankfully I don't need to do that so much on mine, because its only powering the decoder, servo and CPU 🙂.
Cheers,
Phil
Hi mb, mikewong and wckong
Sending SM CD950 (size 26,6MB) is failed. I just have returned my email included SM CD950 from System Administrator.
Try find another email address.
JKoch
Sending SM CD950 (size 26,6MB) is failed. I just have returned my email included SM CD950 from System Administrator.
Try find another email address.
JKoch
Phil,
The best part is TI has a free sample program and I got two pairs FREE.
That is the best DIY modding experience so far!
I am afraid to put the op amp adapters in to roll op amps. When I finally pick one I have to take it out and resolder in the op amp permanently (purist). Too many opportunities (remember I am a beginner) to destroy my PCB so I did a lot of reading about which work well in the Rotel and the OPA627s won. Plus they have a low offset voltage so jumping the AC coupling caps might also improve the sound a little (according to what I read). Plus they are warm, something the Rotel can use a little more of.
Yes I agree the PS is a necessary problem and needs to be improved and maybe I will go as far as you suggest but something has to be done.
I listen to my music loud sometimes so I will go from transistors directly to a muting circuit to prevent further heartache. The transistors I put in are better and the first pair will control the relay anyway (not a total waste).
The FET circuit looks like the best value approach to bias to Class A but I want to pick the best way (there are several it seems).
All this practice and then I will do the Philips next. Rotels are easy to find if I toast it and Rotel can still support most of it. I don't see too many 950s here in the US so I will try mods on that one after I get experience. I would like to see the TDA1547 reach its full potential. I am sure I will have to research different op amps and other details to get the most out of the philips.
CD Players are like kids, each has their own needs to help them reach their full potential too.
Cheers and Thanks!
Regards//Keith
The best part is TI has a free sample program and I got two pairs FREE.
That is the best DIY modding experience so far!
I am afraid to put the op amp adapters in to roll op amps. When I finally pick one I have to take it out and resolder in the op amp permanently (purist). Too many opportunities (remember I am a beginner) to destroy my PCB so I did a lot of reading about which work well in the Rotel and the OPA627s won. Plus they have a low offset voltage so jumping the AC coupling caps might also improve the sound a little (according to what I read). Plus they are warm, something the Rotel can use a little more of.
Yes I agree the PS is a necessary problem and needs to be improved and maybe I will go as far as you suggest but something has to be done.
I listen to my music loud sometimes so I will go from transistors directly to a muting circuit to prevent further heartache. The transistors I put in are better and the first pair will control the relay anyway (not a total waste).
The FET circuit looks like the best value approach to bias to Class A but I want to pick the best way (there are several it seems).
All this practice and then I will do the Philips next. Rotels are easy to find if I toast it and Rotel can still support most of it. I don't see too many 950s here in the US so I will try mods on that one after I get experience. I would like to see the TDA1547 reach its full potential. I am sure I will have to research different op amps and other details to get the most out of the philips.
CD Players are like kids, each has their own needs to help them reach their full potential too.
Cheers and Thanks!
Regards//Keith
Phil,
I red many opinion about modification fo CDs, and I intend to use:
- LM6172 as output op-amps (in net some people claim that the op-amp are suitable for bitstrem CDs - gives more detailed sound than popular AD825),
- LM340T5 to supply digaital ICs
- LT1085 to supply analog ICs
And:
- IEC inlet + RFI Filter,
- replace all bypassing caps to better quality,
- add many new baypassing caps,
- remove all output transistors.
Than more dificult decission I have to chose good Clock. I still searching net to find good application for SAA7350. Maybe you have a suitable solution of this problem.
JKoch
I red many opinion about modification fo CDs, and I intend to use:
- LM6172 as output op-amps (in net some people claim that the op-amp are suitable for bitstrem CDs - gives more detailed sound than popular AD825),
- LM340T5 to supply digaital ICs
- LT1085 to supply analog ICs
And:
- IEC inlet + RFI Filter,
- replace all bypassing caps to better quality,
- add many new baypassing caps,
- remove all output transistors.
Than more dificult decission I have to chose good Clock. I still searching net to find good application for SAA7350. Maybe you have a suitable solution of this problem.
JKoch
Re😛ost#30
Hi JKoch,
Sorry. Would you kindly email sm to this address:
wckong1806@yahoo.com
if you had sent it successfully to QSerraTico Tico ?
Best regards.
Kong
Hi JKoch,
Sorry. Would you kindly email sm to this address:
wckong1806@yahoo.com
if you had sent it successfully to QSerraTico Tico ?
Best regards.
Kong
Hi Wckong
I just have sent the SM to you. QSerraTico Tico received the SM on 31st May, I hope.
JKoch
I just have sent the SM to you. QSerraTico Tico received the SM on 31st May, I hope.
JKoch
JKosh, hate to do this as i see many had requested you to send the SM to email. Would be good if you could point me to an url i can download from. Im working on a CD930 which i believe is same as the CD950.......can someone confirm this??
should the url not available, i'm at kompressori_405@hotmail.com
many thks.
should the url not available, i'm at kompressori_405@hotmail.com
many thks.
Hey puginfo,
The CD930 is different in some ways than the CD950. Check your e-mail. What you need is there.
Regards//Keith
The CD930 is different in some ways than the CD950. Check your e-mail. What you need is there.
Regards//Keith
Hi all,
Can anyone who was able to recieve the CD950 SM from JKoch, that knows how and where (free) they can post it to download, can you do that for us people that have small e-mail attachment limits and post the hyperlink here? My e-mail only accepts 16 Mb and this file compressed is over 20 Mb. It is 26.6 Mb uncompressed.
Thanks from all of us who have small ones (e-mail limits that is)!
Regards//Keith
PS Roar, it's done!
Can anyone who was able to recieve the CD950 SM from JKoch, that knows how and where (free) they can post it to download, can you do that for us people that have small e-mail attachment limits and post the hyperlink here? My e-mail only accepts 16 Mb and this file compressed is over 20 Mb. It is 26.6 Mb uncompressed.
Thanks from all of us who have small ones (e-mail limits that is)!
Regards//Keith
PS Roar, it's done!
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