Hello Everybody, I am jumping into the water as a new DIYer and I am either going to have an even finer sounding CD Player or burnt toast! The 865 already sounds pretty sweet for an older, not too expensive CDP. I look forward to it sounding even better. While emailing with a great Tech Support guy at Rotel, he suggested only one Rotel approved Mod. He said to replace the two XR5534A op amps with two AD847 op amps and to replace four 18 ohm resistors R219, R220, R225 and R226 with wire jumpers. I saw previous posts and saw all kinds of suggestions (many were over my head) but none suggested the Rotel approved Mod. The most popular was to replace the stock op amps with the BB OPA627 op amps and do something with resistors and Caps. Anyone know from experience which is better?
I appreciate all suggestions, ideas and opinions, especially the ones based on actual listening experience and satisfaction with these Mods and even better if they have been done on a RCD 865! I thank you all in advance and look forward to sharing all my successes and burnt toast too! Anyone have any jelly?
I appreciate all suggestions, ideas and opinions, especially the ones based on actual listening experience and satisfaction with these Mods and even better if they have been done on a RCD 865! I thank you all in advance and look forward to sharing all my successes and burnt toast too! Anyone have any jelly?






Wah!, Nobody wants to help me make my RCD 865 be the best sounding it can be! Wah!





Please! I am open to all ideas! If it is over my head, I am certainly willing to give it a try! Thanks!
Regards//keith
If you are serious about your 865, which for the record I don’t know, you need to start with a service manual, at the very least a schematic.
A more then basic understanding of the processes is highly recommended if you don’t want to work as a parrot or blind man. Experimenting with well targeted parts of the circuit, one by one, followed by listening tests is the proper way to go.
Of course this is DIY and shouldn’t be taken too seriously but working systematically can save a lot of frustration. 🙂
Here’s one tip as a starter: I read that several connectors on the PDM(?) board tend to have bad connections. Resoldering or eliminating them by wiring directly to the board should cure that.
/Hugo
A more then basic understanding of the processes is highly recommended if you don’t want to work as a parrot or blind man. Experimenting with well targeted parts of the circuit, one by one, followed by listening tests is the proper way to go.
Of course this is DIY and shouldn’t be taken too seriously but working systematically can save a lot of frustration. 🙂
Here’s one tip as a starter: I read that several connectors on the PDM(?) board tend to have bad connections. Resoldering or eliminating them by wiring directly to the board should cure that.
/Hugo
The above advice is of course very sound but some of us have to be parrots because we lack the basic skills and understanding. For reasons known only to the audio gods, there are 600+ pages devoted to modding the Marantz 63/67 series. If you have the courage to read it thru from the beginning you will get a very good idea of the whole process, even if like me you don't understand half of it. Every now and then a nugget will appear that I can slavishly follow to the letter! Having said that, DIY'ing is not for the faint-hearted and any sloppyness will get you toasted parts or a dead machine. DON'T take this as gospel PLEASE, but if your player acceps the 627's, do your self a favour and use
LM4562 instead. They are much cheaper (free actually if you are lucky and they are still being given away for trial), can be plugged right in and past their burn-in period (around 100hours on my CDP) sound bloody marvelous. Of course the benefit of doing this may well depend on doing other things as well
ps another tweak (that will probably get me a slap on the wrist) is to remove the internal fuses and solder a FINE, good quality piece of wire (I had some silver wire from an ancient project that I bought from the people in the UK who made the Passion passive pre kits) across the fuse holder legs. I don't need to tell you to unplug the unit first do I! This is a contraversial tweak but I had an emmediate reduction in subliminal 'dirt'. Soldering a decent power cord in place of the fixed one is also an easy upgrade, assuming it is the fixed type and easily accessable. Cheers!
LM4562 instead. They are much cheaper (free actually if you are lucky and they are still being given away for trial), can be plugged right in and past their burn-in period (around 100hours on my CDP) sound bloody marvelous. Of course the benefit of doing this may well depend on doing other things as well

ps another tweak (that will probably get me a slap on the wrist) is to remove the internal fuses and solder a FINE, good quality piece of wire (I had some silver wire from an ancient project that I bought from the people in the UK who made the Passion passive pre kits) across the fuse holder legs. I don't need to tell you to unplug the unit first do I! This is a contraversial tweak but I had an emmediate reduction in subliminal 'dirt'. Soldering a decent power cord in place of the fixed one is also an easy upgrade, assuming it is the fixed type and easily accessable. Cheers!
KP11520
Do you really want to disable a good working CDplayer?
Do you have anything else to use while the mod's are taking place?
If your not used to modding or even soldering you can be your own worst enemy....
first you need to find some info about your own player
It will probably have a Philips equivilant, maybe a cd850 MK1 or 2.
A picture tells a thousand works..
A schematic tells more.
what dac's are used?
the marantz cd63/67 link is very informative on different ideas which can be crossed to other players but,..... you need to find the dfferences in your player too.
opamps? the 5534's are single amp 8pin package
each brand opamp has it's own characteristic, use a socket and try different ones.
allan
http://www.diyaudio.com/forums/sear...63102415&sortby=lastpost&sortorder=descending
Do you really want to disable a good working CDplayer?
Do you have anything else to use while the mod's are taking place?
If your not used to modding or even soldering you can be your own worst enemy....
first you need to find some info about your own player
It will probably have a Philips equivilant, maybe a cd850 MK1 or 2.
A picture tells a thousand works..
A schematic tells more.
what dac's are used?
the marantz cd63/67 link is very informative on different ideas which can be crossed to other players but,..... you need to find the dfferences in your player too.
opamps? the 5534's are single amp 8pin package
each brand opamp has it's own characteristic, use a socket and try different ones.
allan
http://www.diyaudio.com/forums/sear...63102415&sortby=lastpost&sortorder=descending
KP11520, the other thread on the RCD865 that you are involved in, has links to the service manual for the CD player in question. With a little bit of searching, you can easily find the schematics and even photos of the internals. This way you can learn about this CD player and plan all of the mods - without even opening the CD player. This will also reduce the risk of ESD......please remember to work ESD safe!!!
In summary, it has a Philips CDM4/19 mechanism, SAA7310 decoder and SAA7323 DAC (Ist generation Bitstream). The closest Philips machine is the CD624. It has similar components but a different layout.
KP11520, you are not going to get any definitive answers on exactly what to do with your CD player. Everyone has a different idea of what sounds good and what mods bring an improvement. Some mods (like just exchanging components) don't necessarily bring an improvement - just a change in sound. Other mods like improving the power supplies, circuit layout, grounding and clocking can bring meaningful gains.
The best you can do is to spend a lot of time reading and learning.....before you start soldering. Most of the general mods can be applied to all CD players with a little adaptation.
In summary, it has a Philips CDM4/19 mechanism, SAA7310 decoder and SAA7323 DAC (Ist generation Bitstream). The closest Philips machine is the CD624. It has similar components but a different layout.
KP11520, you are not going to get any definitive answers on exactly what to do with your CD player. Everyone has a different idea of what sounds good and what mods bring an improvement. Some mods (like just exchanging components) don't necessarily bring an improvement - just a change in sound. Other mods like improving the power supplies, circuit layout, grounding and clocking can bring meaningful gains.
The best you can do is to spend a lot of time reading and learning.....before you start soldering. Most of the general mods can be applied to all CD players with a little adaptation.
ESD=easily self-mutilated? All the above is wise and level-headed.
But when you do do something right (it still works!) and it sounds better (well different anyway) what a rush! ever day I look at my Marantz and say to myself "hey dude you actually changed out that laser block and it actually not only works but it cured the problem!" This is beginners luck, don't knock it! Actually the way to go is to buy a 2nd hand Marantz off e-bay and be prepared for the long hawl, maybe even kill something. That way you can either enjoy the fruits of your labor or find that Diyng is not your thing! If you succeed you will have a player that really sings for little dough. Don't hesitate to keep asking. Someone will have the patience to talk you thru it. Back to the Marantz thread! good luck and don't get discouraged.
But when you do do something right (it still works!) and it sounds better (well different anyway) what a rush! ever day I look at my Marantz and say to myself "hey dude you actually changed out that laser block and it actually not only works but it cured the problem!" This is beginners luck, don't knock it! Actually the way to go is to buy a 2nd hand Marantz off e-bay and be prepared for the long hawl, maybe even kill something. That way you can either enjoy the fruits of your labor or find that Diyng is not your thing! If you succeed you will have a player that really sings for little dough. Don't hesitate to keep asking. Someone will have the patience to talk you thru it. Back to the Marantz thread! good luck and don't get discouraged.




Gentlemen,
I want to thank you for getting involved! I appreciate and need the direction. I already have the Service Manual and Schematics from the great Tech Guy from Rotel (first and foremost). I will read all the Marantz Mods (for quite a few days it loks like) to get an education and maybe even a little more confused. Allan, thanks for the hyperlink to Fin's posts. I will learn from that too. I will do only one Mod at a time and the listen for a while. If I do more than one at a time I won't know which one negated the better results. So one at a time only! I will be calculated and neat and precise. I will wear a grounding strap and have a Hakko soldering station (ESD safe). I have desoldering braid (wick), but am open to better ways). I will do my best to practice sound procedures and with a little luck (I will keep my fingers crossed - see above) I will make you all proud! We all had to start somewhere and this is my somewhere! After all, I can't be a Newdie, I mean Newbie forever!
The first Mod will be the op amps. I am leaning towards the 847s because Rotel Service used to do this for their customers and this Mod is straight forward. It seems that the 627s get the most praise but there are additional mods required to tweak the mod to bring out the best results. It seems there are many different opinions on how to achieve these tweaks (jumping pins on the op amps with different value resistors and/or adding Caps somewhere) but there is no general consensus. That worries me because I only want to do this once to reduce my risk of detroying the board. Sockets are a good idea but once you make a decision you have to desolder the socket and permanantly solder the op amps for best results (purist). That's two more times than I want to risk. So the decision will be well researched and thought out and the Mod will be done once unless something significant forces me to change it! This is where I need a quorum to choose the 627 over the 847 and have a significant percentage of you agree on how to tweak these op amps otherwise I will get the 847s from Rotel directly ($17.20 ea.).
After that and listening for a while, the clock will be next. I read that that Mod gets amazing resulrts too! When I get to that point I will need your help with which one and the procedure.
After that IEC inlet with better wire to the power block and better power cord.
Maybe after that, this is up in the air, removing the muting transistors (Ah! Njoe Tjoeb uses a relay instead and that is a good idea but not an option on this unit). I am not sure if I should just remove them or jump them or leave them but I am nowhere that decision or Mod.
And maybe after that, replacing some of the componenets (Caps, resistors, etc.) with higher quality ones.
But back to Mod 1. So gentlemen, is there one definite way to get the most out of the 627s that most agree on or will it be the 847s?
I want to thank you all for my education!




I look forward to your replies!
Regards//Keith
P.S. I do have another CDP to listen to as I make the Mods in the Rotel RCD 865. I have a Philips CD950. Maybe there are some good Mods for that too!
Regards//Keith
Regards//Keith
KP11520 said:P.S. I do have another CDP to listen to as I make the Mods in the Rotel RCD 865. I have a Philips CD950. Maybe there are some good Mods for that too!
Regards//Keith
Which of the two CD players (Rotel RCD865 or Philips CD950) sounds better to you?
Hi Fin.
Which of the two CD players (Rotel RCD865 or Philips CD950) sounds better to me?
You know this is a long story but if you have a minute I will explain my impressions. Back in the early 90s my cousin got married and was getting the itch for a new stereo for their new apartment.. He and I were Business partners in a Home Remodeling company, so every time there was no work in the afternoons we would kill time looking for the system he would buy. I also was getting the itch to do something with my system too. I already had a mint Hafler DH-500, NAD 1020, Infinity RS IIIA speakers and a Turntable that sounded pretty nice. He bought a complete Rotel system including the RCD 865, RB-980BX, RTC-850, Rotel Cassette and a pair of ProAc Studio I Mk II speakers. He eventually upgraded the interconnects and speaker cable. I on the other hand, in our listening travels bought a used, but perfect Nakamichi CR5A and a new DBX. My sister worked at Philips and got me their best at the time CD950 for a great price. I bought from the same retailer as him a Creek T40 FM Tuner. I had lo-end intercomnnects and 10 guage stranded lamp cord for speaker connects.
Listening to the two systems, his blew mine away except for when we made cassettes for out truck stereos from CDs (In the early 90s cassettes were still popular in auto HiFi and we had nice systems and my player had DBX). Overall, his system came to life and mine played recorded music and the more his system broke in, the better it sounded. Mine...just sounded the same. His system would make you tingle, the way it made music sound. It was an incredibly balanced system that was more than the sum of the parts.
Then he got the itch to start upgrading (12 years later). I bought his ProAcs and pushed the Infinitys aside. Then he gave me the RTC-850 and the NAD was pushe daside and my system started to wake up. Recently I bought a Rotel RHB-10 amp from eBay (Mint) and an excellent power cord and interconnects and Speaker cable and replaced the Mid/woofers in the ProAcs. Now I had everything he had and an even better amp except for the CD Player. I was still using the Philips. My system was now amazing. It did many of the things his did. But not all. With the Philips I did hear so much more, better imaging, soundstage, diferentiation between the voice and instruments. But still not as alive and warm as the Rotel 865. I remember listening to Dave Matthews and just tingling with feeling of the presence in the room with the band in a 3d image around him like there was no speakers, just the band in the room. The Philips just doesn't get there.
He broke the button on the Rotel 865 that opens/closes the CD drawer and tried to rig it. He took it apart and extended the switch to come out with rubber extenders (I mean rigged YUK). When he put it together the drawer could now open and close but the player developed a hum in the right channel. He bought a new Arcam and gave me his Rotel and now this is my new project as in this thread. I already have the replacement plastic button controls to be installed and just need to trace the hum. I believe when he took the front apart some if the screws were a few mms longer and may have been placed in the wrong holes and may be shorting something out. But after fixing that (tomorrow maybe) I will put it into my system next to the Philips with another new high quality interconnect and flip back and forth to make sure my impressions are still accurate. Even if they are not, I know I can get even more out of this Rotel than the stock unit sounds (and it sounds very nice). I am hoping to make the 865 sound the best it can be within reason (financially). I also can't begin to tell you about the impact the audiophile interconnects and power cord had on the system, just as significant as the RHB-10 upgrade. But that is another discussion.
And this is how I wound up here in DIYaudio. I hope this helps answer the question in a round about sort of way!

Regards//Keith
Which of the two CD players (Rotel RCD865 or Philips CD950) sounds better to me?
You know this is a long story but if you have a minute I will explain my impressions. Back in the early 90s my cousin got married and was getting the itch for a new stereo for their new apartment.. He and I were Business partners in a Home Remodeling company, so every time there was no work in the afternoons we would kill time looking for the system he would buy. I also was getting the itch to do something with my system too. I already had a mint Hafler DH-500, NAD 1020, Infinity RS IIIA speakers and a Turntable that sounded pretty nice. He bought a complete Rotel system including the RCD 865, RB-980BX, RTC-850, Rotel Cassette and a pair of ProAc Studio I Mk II speakers. He eventually upgraded the interconnects and speaker cable. I on the other hand, in our listening travels bought a used, but perfect Nakamichi CR5A and a new DBX. My sister worked at Philips and got me their best at the time CD950 for a great price. I bought from the same retailer as him a Creek T40 FM Tuner. I had lo-end intercomnnects and 10 guage stranded lamp cord for speaker connects.
Listening to the two systems, his blew mine away except for when we made cassettes for out truck stereos from CDs (In the early 90s cassettes were still popular in auto HiFi and we had nice systems and my player had DBX). Overall, his system came to life and mine played recorded music and the more his system broke in, the better it sounded. Mine...just sounded the same. His system would make you tingle, the way it made music sound. It was an incredibly balanced system that was more than the sum of the parts.
Then he got the itch to start upgrading (12 years later). I bought his ProAcs and pushed the Infinitys aside. Then he gave me the RTC-850 and the NAD was pushe daside and my system started to wake up. Recently I bought a Rotel RHB-10 amp from eBay (Mint) and an excellent power cord and interconnects and Speaker cable and replaced the Mid/woofers in the ProAcs. Now I had everything he had and an even better amp except for the CD Player. I was still using the Philips. My system was now amazing. It did many of the things his did. But not all. With the Philips I did hear so much more, better imaging, soundstage, diferentiation between the voice and instruments. But still not as alive and warm as the Rotel 865. I remember listening to Dave Matthews and just tingling with feeling of the presence in the room with the band in a 3d image around him like there was no speakers, just the band in the room. The Philips just doesn't get there.
He broke the button on the Rotel 865 that opens/closes the CD drawer and tried to rig it. He took it apart and extended the switch to come out with rubber extenders (I mean rigged YUK). When he put it together the drawer could now open and close but the player developed a hum in the right channel. He bought a new Arcam and gave me his Rotel and now this is my new project as in this thread. I already have the replacement plastic button controls to be installed and just need to trace the hum. I believe when he took the front apart some if the screws were a few mms longer and may have been placed in the wrong holes and may be shorting something out. But after fixing that (tomorrow maybe) I will put it into my system next to the Philips with another new high quality interconnect and flip back and forth to make sure my impressions are still accurate. Even if they are not, I know I can get even more out of this Rotel than the stock unit sounds (and it sounds very nice). I am hoping to make the 865 sound the best it can be within reason (financially). I also can't begin to tell you about the impact the audiophile interconnects and power cord had on the system, just as significant as the RHB-10 upgrade. But that is another discussion.
And this is how I wound up here in DIYaudio. I hope this helps answer the question in a round about sort of way!



Regards//Keith
OK - so the Rotel sounds better than the CD950. That is not surprising. The Philips has a TDA1547 DAC which is very high spec and classed as a "high quality"dac by Philips.......however, most don't really like the sound of it reporting that it is dull and lifeless.
I would think that the Rotel is a much better prospect in the long term for modding and improvement than the Philips - assuming that you friend has not damaged it too badly.
If you can sucessfully fix the hum in the Rotel - it then presents the option of practicing on the Philips. If the Rotel sounds better than the Philips (and it should) - there is not much to lose by experimenting on the Philips.
But if you are set on modding the Rotel first....try all of the standard mods like Schottky diodes, better caps, more regulators, better decoupling, better grounding, improved clocking, different opamps, removing muting transistors, damping materials..........
I would think that the Rotel is a much better prospect in the long term for modding and improvement than the Philips - assuming that you friend has not damaged it too badly.
If you can sucessfully fix the hum in the Rotel - it then presents the option of practicing on the Philips. If the Rotel sounds better than the Philips (and it should) - there is not much to lose by experimenting on the Philips.
But if you are set on modding the Rotel first....try all of the standard mods like Schottky diodes, better caps, more regulators, better decoupling, better grounding, improved clocking, different opamps, removing muting transistors, damping materials..........
Fin,
If I am successful removing the hum, then I will probably move forward with the Rotel recommended AD847 op amp upgrade since I have it apart and no one has really commented on a better suggestion. Unless you feel strongly about another op amp or direction and don't mind me challenging your advice to open a healthy discussion (and my enlightenment) about the logic and reasons why! This mod I can handle but more complicated ones I might ask about best practice procedures and what to watch out for.
It seems like you are always helping someone here and I just want to say THANKS MATE for all of us!
Regards//Keith
If I am successful removing the hum, then I will probably move forward with the Rotel recommended AD847 op amp upgrade since I have it apart and no one has really commented on a better suggestion. Unless you feel strongly about another op amp or direction and don't mind me challenging your advice to open a healthy discussion (and my enlightenment) about the logic and reasons why! This mod I can handle but more complicated ones I might ask about best practice procedures and what to watch out for.
It seems like you are always helping someone here and I just want to say THANKS MATE for all of us!
Regards//Keith
Well after opening up the CDP, I found two things.
I found it isn't a RCD 865 BX but a RCD 965 BX. Except for a few small differences on the front panel and some mysterious weight difference of about a pound, they are the same. But the hum isn't a hum. It is an amplified distortion that is much louder than the left channel. The sound is distinguishable but moderately distorted and louder.
I am new at this and don't have any tech equipment (scope, etc). I only have a LCD Digital Multimeter. Do any of you have any ideas that I can handle (I am brave) and don't mind giving me a little guidance and instruction, so I can get this done and onto the first mod. If not, my only choice will be a local shop or Rotel America. All help will be greatly appreciated!!
Regards//Keith

I am new at this and don't have any tech equipment (scope, etc). I only have a LCD Digital Multimeter. Do any of you have any ideas that I can handle (I am brave) and don't mind giving me a little guidance and instruction, so I can get this done and onto the first mod. If not, my only choice will be a local shop or Rotel America. All help will be greatly appreciated!!


Regards//Keith
IMO, you need to find an inexpensive scope- see the other thread on finding a beginner scope. That way, you'll be able to quickly see oscillations, noisy power, and other oddities that are tough to sort out by ear. Stability is a big issue when changing op-amps that have varying bandwidths, different compensation pins, and different output drive capabilities. I've used the 627 in very sensitive instrumentation applications, and it's a remarkable op-amp in terms of offset, noise, and input current, but those may not be the only things to consider for audio.
What you can check is
Is it standard, ie no mods yet?
If it's standard, look for dry joints
If it's not standard, what has been modded?
allan
Is it standard, ie no mods yet?
If it's standard, look for dry joints
If it's not standard, what has been modded?
allan
No Mods..... YET!
From the top side everything looks perfect, I guess I should take out the PCB and look at the solder joints to see that they are shiny and no daylight where the component wires and posts pass through the PCB holes next?
From the top side everything looks perfect, I guess I should take out the PCB and look at the solder joints to see that they are shiny and no daylight where the component wires and posts pass through the PCB holes next?
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