Hi!
I have a 12 year old Naim CDI, which uses the rare, and now unavailable Philips CDM4/22 (or CDM4/27) transport mechanism.
This has now 'died' - the motor hardly spins at all, and sometimes even tries to rotate backwards!
I have spoken to Naim, and they quoted around £500 to get it all up and running. Unfortunately I cannot afford this :-(
I know with the CDI that Naim used to install the CDM9 Pro on later models. Being as the CDM9/44 can be used in place of the CDM9 pro, could this be used to bring my CDI back to life? I don't really want to get rid of it!
Cheers,
- John
I have a 12 year old Naim CDI, which uses the rare, and now unavailable Philips CDM4/22 (or CDM4/27) transport mechanism.
This has now 'died' - the motor hardly spins at all, and sometimes even tries to rotate backwards!
I have spoken to Naim, and they quoted around £500 to get it all up and running. Unfortunately I cannot afford this :-(
I know with the CDI that Naim used to install the CDM9 Pro on later models. Being as the CDM9/44 can be used in place of the CDM9 pro, could this be used to bring my CDI back to life? I don't really want to get rid of it!
Cheers,
- John
If the laser died , all you have to do is just replace the laser arm from any machine equipped with CDM 4/19, and there are thousands of them out there for as low as 20-30Euro. Mostly Philips and Marantz cheap plastics models. The thing is that your player can have other failure or needs trimming,there is no problem with getting parts for replacement , and they are cheap resourced from those same old and cheap Marantz and Philips players but you might need the person that will be able to do it, will know those players and will also know which one to buy to get the replacement. I would do it for a couple of times cheaper than Naim but I live in Poland , so it's quite far away.
All of players from that era that had those CDM transports had the same chips and servos , so getting the parts is no big deal.
Bartek
P.S. No version of CDM 9 will work as this is quite a bit diffrent transport.
All of players from that era that had those CDM transports had the same chips and servos , so getting the parts is no big deal.
Bartek
P.S. No version of CDM 9 will work as this is quite a bit diffrent transport.
Hi Bartek! Many thanks for your helpful reply! I actually think the laser is OK, it's just the motor not spinning, or barely spinning at all, or sometimes spinning in the opposite direction!
Also the nextel ring has been removed from the hub, which isn't too much of a problem if I use a Naim puck with more than one rubber ring. The spindle has to be from the CDM4/22 or 4/27 though for it's magnetic properties. I tried a 4/19 and the puck would not magnetically 'stick' to the hub at all.
Perhaps I could send you the mechanism on it's own - that way it would be considerably cheaper? It's easily removed from the casing.
Cheers,
- John
Also the nextel ring has been removed from the hub, which isn't too much of a problem if I use a Naim puck with more than one rubber ring. The spindle has to be from the CDM4/22 or 4/27 though for it's magnetic properties. I tried a 4/19 and the puck would not magnetically 'stick' to the hub at all.
Perhaps I could send you the mechanism on it's own - that way it would be considerably cheaper? It's easily removed from the casing.
Cheers,
- John
CDM 4/22 or 4/27 is probably equipped with brushless motor the same as CDM1MKII and CDM2, but quite diffrent from CDM 4.
Also, I suppose the failure will be not in the motor itself but in electronics driving it that are located on the main board (I've had similar failures before). Can you get a close pictures of the CD inside? So I can closely see the transport and the main board with the chips. If not on the forum you can send them to zygibajt@o2.pl
Bartek
Also, I suppose the failure will be not in the motor itself but in electronics driving it that are located on the main board (I've had similar failures before). Can you get a close pictures of the CD inside? So I can closely see the transport and the main board with the chips. If not on the forum you can send them to zygibajt@o2.pl
Bartek
Maybe difference is only the magnetic spindle?
I would agree that there is a likely problem with the driving electronics for the CDM, however, CDMs can go a bit stuppid if the laser is not reading the disc. Having played with some std Marantz/Philips CDM4/19 players has also shown me that if you lift the clamp during play and the CD slips a little, this can also send the unit bonkers. So if the rubber grippy stuff obn the spindle is deteriorated it could cause some problems but only if the thng actually tries to spin up and gets to a fair speed.
WRT swapping lasers/mechs. I have with some "force" removed a CDM4 spindle before but yours has the deteriorated rubber problem as well so getting a new cdm4 and then swapping the magnetic spindle may be a waste of time as your spindle is dodgy.
The cdm9/44 plastic spindle also uses a magnet and I think one could remove this magnet out of the plastic and glue it into a std CDM4 spindle.
I may have a CDM9 spindle spare but I am in South Africa and I would have to look in the boxes and boxes and boxes....
If you can get your hands on a working CDM4 for little money I would get one and fit it into the naim. You can "clamp" a CD down with a little blue tack on the spindle. This at least will tell you if you have a laser/motor problem or an electronic one.... And you can always hamster the laser for the future if the pronblem is electronic....
I would agree that there is a likely problem with the driving electronics for the CDM, however, CDMs can go a bit stuppid if the laser is not reading the disc. Having played with some std Marantz/Philips CDM4/19 players has also shown me that if you lift the clamp during play and the CD slips a little, this can also send the unit bonkers. So if the rubber grippy stuff obn the spindle is deteriorated it could cause some problems but only if the thng actually tries to spin up and gets to a fair speed.
WRT swapping lasers/mechs. I have with some "force" removed a CDM4 spindle before but yours has the deteriorated rubber problem as well so getting a new cdm4 and then swapping the magnetic spindle may be a waste of time as your spindle is dodgy.
The cdm9/44 plastic spindle also uses a magnet and I think one could remove this magnet out of the plastic and glue it into a std CDM4 spindle.
I may have a CDM9 spindle spare but I am in South Africa and I would have to look in the boxes and boxes and boxes....
If you can get your hands on a working CDM4 for little money I would get one and fit it into the naim. You can "clamp" a CD down with a little blue tack on the spindle. This at least will tell you if you have a laser/motor problem or an electronic one.... And you can always hamster the laser for the future if the pronblem is electronic....
Hi!
I don't seem to have a problem with CD slippage, as the puck holds the CD down pretty well. Also I have a very thin rubber washer which I can use for any problem discs, so I don't think disc slippage is the problem.
I think maybe - as you've both suggested - it's either a driver board problem, or something wrong with the motor.
With Bartek's kind help I'm going to have a go at replacing the laser assembley with one from a CDM4/19 and see if this makes a difference. If not that just leaves the motor I guess. I will try your idea first though of just running the CDM 4/19 in there with a make-shift CD clamp just to see if it's the driver board, or mechanism which is at fault.
Thanks for your help, and wish me luck ;-)
- John
I don't seem to have a problem with CD slippage, as the puck holds the CD down pretty well. Also I have a very thin rubber washer which I can use for any problem discs, so I don't think disc slippage is the problem.
I think maybe - as you've both suggested - it's either a driver board problem, or something wrong with the motor.
With Bartek's kind help I'm going to have a go at replacing the laser assembley with one from a CDM4/19 and see if this makes a difference. If not that just leaves the motor I guess. I will try your idea first though of just running the CDM 4/19 in there with a make-shift CD clamp just to see if it's the driver board, or mechanism which is at fault.
Thanks for your help, and wish me luck ;-)
- John
CDM9 spindle magnet is to big for CDM4 spindle
I dug this stuff out and my idea of using the 9 spindle's magnet will not work as it's dia is to large. You could probably file it down to fit but it will probably be easier to try and find a circular little magnet to fit onto the CDM4/19 spindle.... (If that is where your problem is..)
Let us know how you progressed!
G
I dug this stuff out and my idea of using the 9 spindle's magnet will not work as it's dia is to large. You could probably file it down to fit but it will probably be easier to try and find a circular little magnet to fit onto the CDM4/19 spindle.... (If that is where your problem is..)
Let us know how you progressed!
G
Hi tubenut!
Thanks for your suggestions and help - much appreciated. My current plan is to take the CDM4/19 from my old Rotel CD player and try that out in the Naim. If this works and reads the disc, then I'll take the laser out and fit that into the CDM4/27 and hope for the best ;-)
Unfortunately the Rotel is at my parents house so I have to wait two loooong weeks bwfore I can try this :-(
Failing that, I'm trying to make a list of CD players which used either the CDM4/22 or the CDM4/27 mechanism, bu tno thaving much luck..... Possibly the Mission PCM7000 used it, btu trying to get that confirmed. Another possibility is - of course - a Philips player, but again I can find no information on this.
Cheers,
- John
Thanks for your suggestions and help - much appreciated. My current plan is to take the CDM4/19 from my old Rotel CD player and try that out in the Naim. If this works and reads the disc, then I'll take the laser out and fit that into the CDM4/27 and hope for the best ;-)
Unfortunately the Rotel is at my parents house so I have to wait two loooong weeks bwfore I can try this :-(
Failing that, I'm trying to make a list of CD players which used either the CDM4/22 or the CDM4/27 mechanism, bu tno thaving much luck..... Possibly the Mission PCM7000 used it, btu trying to get that confirmed. Another possibility is - of course - a Philips player, but again I can find no information on this.
Cheers,
- John
CDM9 vs CDM4
I hope you get lucky with the old Rotel unit etc.
The CDM9 and CDM4 are very different. They can both run of the TDA8809 and 8809 servo chips but there is no laser focus and current adjustent with a CDM9. They are also a completly different shape. Have a look at some pictures here: http://www.ersatzteil.justone-schnepel.de/html/bildergallerie1.html
I think you would need "some kind of conversion kit" from Naim to fit a CDM9..... Possibly a servo pcb and a different loading tray.
Good CDM9 mechs are harder to get then CDM4. There are literally 1000s of used CDM4 based players (cheap ones) out there that function well and are a good source for genuine lasers.
Most of the cdm9 spares offered are refurbished or pirate and not that good and there are only a handful of players by comparison that used the cdm9 that you could scavenge from. CDM9 also does not last as long as CDM4.
Have you contacted avondale audio at all? They claim to be far cheaper on repairs of Naim then Naim and make big claims as to their ability to refurb Naim CD3 players for a fraction of the Naim charge. Perhaps they can help with the CDI.... They know their stuff from what I have read. They are in the UK.
Most of the Philips based CDM4 players used a springloaded mechanical clamp and the spindle is not likely to be magnetic... I can not think of one that I have seen that used a magnetic clamp. Krell on the old MD2 I think used a heavy non magnetic brass puck to clamp the disc. This is dumb I think as the motor and servos work harder to slow the disc down as the player advances through the disc.
I think the CDM4 based players you should try and find are ones that are top loaders.....
G
I hope you get lucky with the old Rotel unit etc.
The CDM9 and CDM4 are very different. They can both run of the TDA8809 and 8809 servo chips but there is no laser focus and current adjustent with a CDM9. They are also a completly different shape. Have a look at some pictures here: http://www.ersatzteil.justone-schnepel.de/html/bildergallerie1.html
I think you would need "some kind of conversion kit" from Naim to fit a CDM9..... Possibly a servo pcb and a different loading tray.
Good CDM9 mechs are harder to get then CDM4. There are literally 1000s of used CDM4 based players (cheap ones) out there that function well and are a good source for genuine lasers.
Most of the cdm9 spares offered are refurbished or pirate and not that good and there are only a handful of players by comparison that used the cdm9 that you could scavenge from. CDM9 also does not last as long as CDM4.
Have you contacted avondale audio at all? They claim to be far cheaper on repairs of Naim then Naim and make big claims as to their ability to refurb Naim CD3 players for a fraction of the Naim charge. Perhaps they can help with the CDI.... They know their stuff from what I have read. They are in the UK.
Most of the Philips based CDM4 players used a springloaded mechanical clamp and the spindle is not likely to be magnetic... I can not think of one that I have seen that used a magnetic clamp. Krell on the old MD2 I think used a heavy non magnetic brass puck to clamp the disc. This is dumb I think as the motor and servos work harder to slow the disc down as the player advances through the disc.
I think the CDM4 based players you should try and find are ones that are top loaders.....
G
Thanks!
Yes I contacted Avondal Audio, and they said they're looking into this spares-for-CDI situation. I will try them again in couple of months if I have no luck.
Didn't realise the CDM9 was so different - guess Naim probably would offer some kind of conversion kit if this is the case. So that just leaves me with trying to get a second-hand CDM 4/22 or 4/27, but I'm hoping just changing the laser for one from my CDm4/19 will do the job.
Naim told me that the CDM4/22 and 4/27 were the only ones with spindles with the correct magnetic properties to work properly with their puck design.
Will keep you updated.
Cheers,
- John
Yes I contacted Avondal Audio, and they said they're looking into this spares-for-CDI situation. I will try them again in couple of months if I have no luck.
Didn't realise the CDM9 was so different - guess Naim probably would offer some kind of conversion kit if this is the case. So that just leaves me with trying to get a second-hand CDM 4/22 or 4/27, but I'm hoping just changing the laser for one from my CDm4/19 will do the job.
Naim told me that the CDM4/22 and 4/27 were the only ones with spindles with the correct magnetic properties to work properly with their puck design.
Will keep you updated.
Cheers,
- John
Well I got around to fitting a mint condition (and def. working!) laser from a CDM4/19 into the CDM4/27 transport. Cleaned the 4/27 motor and lightly re-oiled as well whilst I was at it.
The result? Still same problem as before
!!!
The disc rotates slowly about 2 or 3 times in the correct direction then I get the error message on the display. So, it's not the laser, I don't THINK it's the motor, so perhaps it's something on the control board? I noticed there's two trim pots on the seperate control board - no markings though. There's also a gain pot on the motor control board located directly beneath the motor on the transport itself.
Looks like this is a job for a professional then as I haven't a clue about setting these things unelss anyone can offer any advice here?
Cheers,
- John
The result? Still same problem as before
!!!The disc rotates slowly about 2 or 3 times in the correct direction then I get the error message on the display. So, it's not the laser, I don't THINK it's the motor, so perhaps it's something on the control board? I noticed there's two trim pots on the seperate control board - no markings though. There's also a gain pot on the motor control board located directly beneath the motor on the transport itself.
Looks like this is a job for a professional then as I haven't a clue about setting these things unelss anyone can offer any advice here?
Cheers,
- John
Control cct then I guess....
Hi
I am on a little bit of leave until 29/3 so this is from home...
Looks like it is the servo cct then. In a way a good deal as chips are easy to find and cheaper then mechs...
Not sure where you should start though.
Jean Paul is a bit of a Philips CD mech Guru. He may well be able to give some pointers.
What chip set does the player use? TDA5708 & 5709 or TDA8808 and 8809?
Hope for you it is 57 series, they are not surface mount. The two trimmer pots, 22 K and 4K7 possibly are for laser focus and current. Not likely to be your problem...
I just sorted a Mission PCMII player, CDM4/11 (first I have seen, looks like a CDM2 but with a 4 laser and perhaps a hall motor). Found the neg 12 V supply was down. Locked motor rock solid while laser was trying to focus.
Hi
I am on a little bit of leave until 29/3 so this is from home...
Looks like it is the servo cct then. In a way a good deal as chips are easy to find and cheaper then mechs...
Not sure where you should start though.
Jean Paul is a bit of a Philips CD mech Guru. He may well be able to give some pointers.
What chip set does the player use? TDA5708 & 5709 or TDA8808 and 8809?
Hope for you it is 57 series, they are not surface mount. The two trimmer pots, 22 K and 4K7 possibly are for laser focus and current. Not likely to be your problem...
I just sorted a Mission PCMII player, CDM4/11 (first I have seen, looks like a CDM2 but with a 4 laser and perhaps a hall motor). Found the neg 12 V supply was down. Locked motor rock solid while laser was trying to focus.
Hi Tubenut!!
Thanks for your reply. Yes I think it muct be one of the chips. Unfortunately they all look like surface mount jobs, so I don't think I can replace them myself - I just don't have the tools!
I'm at my parents house for the Easter break, but will get those chip numbers from the servo cct when I get back to London. I did read somewhere about replacing a 33uF cap on the board - tried this but didn't make any difference. I found out the hard way it's VERY difficult to desolder components from these old cct boards - the tracks lift up so easily, never had this problem before.
Cheers,
- John
Thanks for your reply. Yes I think it muct be one of the chips. Unfortunately they all look like surface mount jobs, so I don't think I can replace them myself - I just don't have the tools!
I'm at my parents house for the Easter break, but will get those chip numbers from the servo cct when I get back to London. I did read somewhere about replacing a 33uF cap on the board - tried this but didn't make any difference. I found out the hard way it's VERY difficult to desolder components from these old cct boards - the tracks lift up so easily, never had this problem before.
Cheers,
- John
Probably TDA8809 and 8808
They are a swine to remove....
If you do not have access to a professional tool to remove these (hot air) best bet is to cut all the legs of the chip and then with tweezers remove one leg at a time. Then solder suck and wick the board clean.
Have you checked that the PSU is fine? Check all this before attempting TDA8808/9 removal!!! It may also be worth squirting some lectroclean or similar into the 4.7 and 22 K pots for focus and laser current.
Seeing as you have established that it is not a laser/motor fault perhaps it is time for handing it over. I have unsuccesfully (read: broken tracks) removed 8808 before. Now I would only attemt it as described above and then with extreme caution....
Regards
They are a swine to remove....
If you do not have access to a professional tool to remove these (hot air) best bet is to cut all the legs of the chip and then with tweezers remove one leg at a time. Then solder suck and wick the board clean.
Have you checked that the PSU is fine? Check all this before attempting TDA8808/9 removal!!! It may also be worth squirting some lectroclean or similar into the 4.7 and 22 K pots for focus and laser current.
Seeing as you have established that it is not a laser/motor fault perhaps it is time for handing it over. I have unsuccesfully (read: broken tracks) removed 8808 before. Now I would only attemt it as described above and then with extreme caution....
Regards
Hi folks!
Been a while since I last posted about this...
Well in a bit of a last ditch effort had another attempt at resurrecting my Naim CDI from the dead. Not sure exactly what I did apart from replacing a few caps and 'blindly' moving both pots to approximately central positions.
IT NOW READS DISCS EVERY TIME & PLAYS PERFECTLY - WOOOHOOOOOEY!!!!!! Talk about chuffed to bits!! It does have trouble quickly finding anything past track 8-10ish, so it undoubtedly needs a fine adjustment by someone in the know. However once it gets to the track it plays fine.
Now however I'm a little reticant about leaving it switched on. The reason is one of the caps I replaced on the Philips CDM servo board I had to make an educated guess at as to it's polarity on the board. It's the 33uF cap to anyone who might know this board. Reason is I lost the diagram I'd made showing polarities of all the caps - aghhh! I don't want to revel in the sound of my CDI only to hear a huge bang as that cap explodes and blows a hole through the circuit board!! I do have other CDM boards to hand but the 33uF cap is in a different place each time, so I can't use that as a visual reference...
Now, one side of this 33uF/50v cap leads to pin 20 of a TDA8809T chip, which is labelled as 'Internal Reference Voltage Output'. The other side of the cap sees Pin 7 of a TCA0372DP2 chip, which is labelled as 'Inputs A'. Now I'm ASSUMING that logically the + side of the cap sees Pin 20, and the - side of the cap sees Pin 7 ?
http://www.onsemi.com/pub/Collateral/TCA0372-D.PDF
http://www.datasheetcatalog.com/datasheets_pdf/T/D/A/8/TDA8809T.shtml
I mean it seems to work fine. If the cap WAS incorrectly mounted, surely the Naim wouldn't it work at all? How long would the cap take to blow if it WAS incorrectly positioned?
Any comments, or - even better - anyone else who might be familier with the CDM 4/22 servo board?
Cheers!
- John
P.S. Yes I guess I could 'cheat' and use a non-polar 33uF cap, but that wouldn't be nearly as much fun would it ;-)
Been a while since I last posted about this...
Well in a bit of a last ditch effort had another attempt at resurrecting my Naim CDI from the dead. Not sure exactly what I did apart from replacing a few caps and 'blindly' moving both pots to approximately central positions.
IT NOW READS DISCS EVERY TIME & PLAYS PERFECTLY - WOOOHOOOOOEY!!!!!! Talk about chuffed to bits!! It does have trouble quickly finding anything past track 8-10ish, so it undoubtedly needs a fine adjustment by someone in the know. However once it gets to the track it plays fine.
Now however I'm a little reticant about leaving it switched on. The reason is one of the caps I replaced on the Philips CDM servo board I had to make an educated guess at as to it's polarity on the board. It's the 33uF cap to anyone who might know this board. Reason is I lost the diagram I'd made showing polarities of all the caps - aghhh! I don't want to revel in the sound of my CDI only to hear a huge bang as that cap explodes and blows a hole through the circuit board!! I do have other CDM boards to hand but the 33uF cap is in a different place each time, so I can't use that as a visual reference...
Now, one side of this 33uF/50v cap leads to pin 20 of a TDA8809T chip, which is labelled as 'Internal Reference Voltage Output'. The other side of the cap sees Pin 7 of a TCA0372DP2 chip, which is labelled as 'Inputs A'. Now I'm ASSUMING that logically the + side of the cap sees Pin 20, and the - side of the cap sees Pin 7 ?
http://www.onsemi.com/pub/Collateral/TCA0372-D.PDF
http://www.datasheetcatalog.com/datasheets_pdf/T/D/A/8/TDA8809T.shtml
I mean it seems to work fine. If the cap WAS incorrectly mounted, surely the Naim wouldn't it work at all? How long would the cap take to blow if it WAS incorrectly positioned?
Any comments, or - even better - anyone else who might be familier with the CDM 4/22 servo board?
Cheers!
- John
P.S. Yes I guess I could 'cheat' and use a non-polar 33uF cap, but that wouldn't be nearly as much fun would it ;-)
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