Hi,
Is anyone can help me to solve my Accuphase DP-80 transport problem which currently is unable to read any CD?
The transport was working fine in one of the day when I tried the new 75 ohm digital link cable to my DAC. Previously I was using the TOSlink cable and think of changing it to 75 ohm cable.
Hooked up both cables to my DAC and did an input selection on DAC, started to play a song from my transport. Everything sounds good from both TOSlink and 75 ohm cable.
Problem happened when I changed the CD, after loaded the second CD in the transport and started to play it. It no longer read the CD anymore and no track number was displayed on the front panel. After few seconds, the tray opened by itself and tried a few CDs but with the same result.
First thing come in my mind was the laser pick-up failure (Sony BU-1C) but sad to accept this because the pick-up was replaced less than a year.
I have a spare laser pick-up bought from eBay same as the first one and happy to replace it onto the transport. Shocked to me when the transport was still unable to read any CD and the tray opened after few seconds. The disc motor run for few seconds but stopped before CD was ejected.
Sad to see this result because both laser pick-ups were claimed to be new and bought from the same seller from eBbay.
Is anyone has the Accuphase DP-80 service manual? Hope to get some idea what is going to the transport from the manual or any idea what happened to the transport?
Sorry for the lengthy grandmother story here and thanks for reading.
Regards,
flyong
Is anyone can help me to solve my Accuphase DP-80 transport problem which currently is unable to read any CD?
The transport was working fine in one of the day when I tried the new 75 ohm digital link cable to my DAC. Previously I was using the TOSlink cable and think of changing it to 75 ohm cable.
Hooked up both cables to my DAC and did an input selection on DAC, started to play a song from my transport. Everything sounds good from both TOSlink and 75 ohm cable.
Problem happened when I changed the CD, after loaded the second CD in the transport and started to play it. It no longer read the CD anymore and no track number was displayed on the front panel. After few seconds, the tray opened by itself and tried a few CDs but with the same result.
First thing come in my mind was the laser pick-up failure (Sony BU-1C) but sad to accept this because the pick-up was replaced less than a year.
I have a spare laser pick-up bought from eBay same as the first one and happy to replace it onto the transport. Shocked to me when the transport was still unable to read any CD and the tray opened after few seconds. The disc motor run for few seconds but stopped before CD was ejected.
Sad to see this result because both laser pick-ups were claimed to be new and bought from the same seller from eBbay.
Is anyone has the Accuphase DP-80 service manual? Hope to get some idea what is going to the transport from the manual or any idea what happened to the transport?
Sorry for the lengthy grandmother story here and thanks for reading.
Regards,
flyong
In my experience, which goes back to the dawn of cd, BU-1C laser/mech units NEVER fail. They only ever need proper adjustment and *proper* lubrication. From the sound of it, assuming the laser/mech replacement was done competently, yours most likely has a lubrication issue. To diagnose, simply turn off power, then, onto a padded surface, tilt the unit forward until it is fully or almost sitting on it's face, then return it to normal orientation. Now try playing a disc. If the disc starts up fine, then you pretty darn definitely just need proper lubrication on the laser's tracking sled guide rails. The tracking sled is a "linear motor", essentially a precisely positionable solenoid, which is infinitely durable & reliable, with the only maintenance/critical issue being the guide rail grease. You CAN'T USE JUST ANY GREASE! You need a very specific sort of lub that is halfway between a grease and an oil, slick enough to give no resistance to movement, but viscous enough to maintain a slick film between two pieces of scraping metal. A "new" BU-1C will have been sitting on a shelf for at least 20 years, so that lub absolutely can NOT be relied upon, so no surprise if it's the problem. Your challenge will be to find the right oil-grease.
Next step is to observe, internally, what happens when you operate the mech. Power up, then open the tray. Manually move the laser sled out back from the center an inch or so. Tell the tray to close, with no disc, and you should see the sled move right back to center position, then the laser should light(turn off room lights & you should easily see red glow in lens, without looking straight in) and lens should move up & down 2-3 times. If this is what happens, now load a disc. Does disc spin?
Hi Stephensank,
First for the laser sled, it does move back to center position after the tray closed.
For the laser light, it is hard to see through naked eye but I used digital camera to focus on the lens, I can see the red glow in the lens after the tray closed. However, both old and new laser pick-up I can see the laser light....
Something can't explain, the old mech motor was able to spin after loading the disc but last for few seconds only, after that the tray ejected the disc. For the new laser pick-up mech, the motor doesn't spin at all, I remembered when the first time I changed the pick-up, the motor did spin as the old mech and couldn't read the disc before ejected the disc.
I am thinking to switch the motor from old pick-up to the new one, but it seems like not easy to remove.
The laser is able to light up, is it meant that the diode is good? I have no idea what to do now.
Thank you for all the suggestions.
First for the laser sled, it does move back to center position after the tray closed.
For the laser light, it is hard to see through naked eye but I used digital camera to focus on the lens, I can see the red glow in the lens after the tray closed. However, both old and new laser pick-up I can see the laser light....
Something can't explain, the old mech motor was able to spin after loading the disc but last for few seconds only, after that the tray ejected the disc. For the new laser pick-up mech, the motor doesn't spin at all, I remembered when the first time I changed the pick-up, the motor did spin as the old mech and couldn't read the disc before ejected the disc.
I am thinking to switch the motor from old pick-up to the new one, but it seems like not easy to remove.
The laser is able to light up, is it meant that the diode is good? I have no idea what to do now.
Thank you for all the suggestions.
If the tray opens by itself, then there usually is something amiss with tray close detection (bad switch contact etc.). These units also use a belt in the tray mechanism though, which may be worn and giving problems, i.e. by proper end position not being reached. Try loading a CD with the unit on its side (tilted as far as needed to keep the CD from falling down).
In new pickups there often is a solder bridge across the laser diode that is supposed to prevent ESD damage while the cable is not yet attached. Check that, too.
In new pickups there often is a solder bridge across the laser diode that is supposed to prevent ESD damage while the cable is not yet attached. Check that, too.
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From here, it gets difficult to help by "remote control". While we are sure your laser diode works, we can't be sure that it is outputting adequate light, without an optical laser power meter, e.g., Leader LPM8000(not very expensive to buy used). The output spec for that laser is 0.24mW, in case you do get an LPM. It will fail to maintain focus if it is lower than about 0.20mW.
Referencing the last poster, it is normal for this unit to "spit out the disc" if it can "see" that a disc has been loaded, i.e., not an empty tray, but fails to read properly.
All we are sure of as yet is that a)laser is lighting, and b)sled is lub'd well enough to allow closure of the inside limit switch, allowing laser lighting & focus search. We don't know yet if focus lock is achieved, thus don't know yet if platter motor is failing to spin up because focus is not achieved or if there is a platter motor drive problem. The way to *mostly* tell if focus has locked but platter motor/motor-drive-circuit is the problem is to gently manually spin the cd(clockwise) just after loading and listen for a "squealing" sound from the laser's tracking coils. If you hear the squeal, then focus has locked and there is a problem with the motor drive circuits(these never have actual motor faults that I have ever seen, at least).
And, btw, you would not see laser lighting if the static protection shorting jumper was still in place.
Referencing the last poster, it is normal for this unit to "spit out the disc" if it can "see" that a disc has been loaded, i.e., not an empty tray, but fails to read properly.
All we are sure of as yet is that a)laser is lighting, and b)sled is lub'd well enough to allow closure of the inside limit switch, allowing laser lighting & focus search. We don't know yet if focus lock is achieved, thus don't know yet if platter motor is failing to spin up because focus is not achieved or if there is a platter motor drive problem. The way to *mostly* tell if focus has locked but platter motor/motor-drive-circuit is the problem is to gently manually spin the cd(clockwise) just after loading and listen for a "squealing" sound from the laser's tracking coils. If you hear the squeal, then focus has locked and there is a problem with the motor drive circuits(these never have actual motor faults that I have ever seen, at least).
And, btw, you would not see laser lighting if the static protection shorting jumper was still in place.
Hi,
Thank you for all the reply and suggestion.
I guess even the new laser pick-up that I have changed, it has something not right. This is because the motor did not spin the disc and I manually turned it to make the motor spin but nothing responded from the lens.
Without disc, I can see the new lens seems like focus (the sled moves and lens up and down) for a while but after that, the sled moves further away from the motor up to the end of the guide rail. What the weird response of the new laser pick-up!!
I believe the CD player had gone beyond someway that I can get it back to work, the hope is slim and may need the professional technician help on this.
Thank you for all the responses from the forum and at least I learnt something there.
Thank you for all the reply and suggestion.
I guess even the new laser pick-up that I have changed, it has something not right. This is because the motor did not spin the disc and I manually turned it to make the motor spin but nothing responded from the lens.
Without disc, I can see the new lens seems like focus (the sled moves and lens up and down) for a while but after that, the sled moves further away from the motor up to the end of the guide rail. What the weird response of the new laser pick-up!!
I believe the CD player had gone beyond someway that I can get it back to work, the hope is slim and may need the professional technician help on this.
Thank you for all the responses from the forum and at least I learnt something there.
Well, if you don't have anyone there in Singapore you know you can trust with this lovely machine, I would be happy to get it back up & running for you. Shipping costs will be quite substantial, but I have 100% confidence I would be able to have it back in perfect working order for 250usd or less.
You can find my info at stephensank.com.
It's really too darn nice to simply give up on.
You can find my info at stephensank.com.
It's really too darn nice to simply give up on.
Problem with my Philips CDM Pro 2 LF transport
I have assembled a CD transport bought from Tentlabs which uses Philips CDM Pro 2 LF transport. I have been using this transport using external clock with Audio Notes DAC 4.1. This has been working very nicely all these days. One fine morning I noticed that it refuses to read any CDs . Luckily, I had a spare brand new transport and I replaced it. Ir started reading all the original disc but refused to read some of my CD RW discs. I tried these discs to my Alesis recorder and reads nicely. Is there any way to increase the laser power? If yes, how does one do it. I could see a pot in the PCB Of the driver board odf CDM Pro 2. Will appreciate for your help.
I have assembled a CD transport bought from Tentlabs which uses Philips CDM Pro 2 LF transport. I have been using this transport using external clock with Audio Notes DAC 4.1. This has been working very nicely all these days. One fine morning I noticed that it refuses to read any CDs . Luckily, I had a spare brand new transport and I replaced it. Ir started reading all the original disc but refused to read some of my CD RW discs. I tried these discs to my Alesis recorder and reads nicely. Is there any way to increase the laser power? If yes, how does one do it. I could see a pot in the PCB Of the driver board odf CDM Pro 2. Will appreciate for your help.
I hate to be the bearer of bad news, but the "Pro 2 LF" is little more than a dirt cheap CDM12 unit, just wrapped in a fancy metal chassis & with a better platter motor. The laser itself & the tracking drive is essentially identical to the cheapest CDM12/VAM12xx junk. All of these CDM are not made by Philips, but by Daisy Laser in China, and I very much doubt that they give the "Pro" version(a moniker that I consider an oxymoron in this case) any special quality control versus the cheapest versions. So, it's just as likely as the cheap line that any replacement laser or whole CDM unit you'd find for this "Pro" series will be less than perfect performance. In my recent experience, you have, at best, a 60% chance of a new one working 100% properly, regardless of what specific model of this CDM12-series junk you're buying. And, in my experience, because these are based around auto-adjusting servo chips, a fault like you are describing will not be curable by adjusting laser power, which is likely the only adjustment available, as it is almost certainly a production variance in the receiving side, the PD array, that is just on the edge of range of the auto-servo chip. So, I'd say you need to get yet another new laser or whole CDM and just pray it works properly, and return the current one if you can for a refund.
When a unit is designed around a particular laser/mech, it is rarely feasible to alter it to use an entirely different one. Don't know of any 'drop in' alternative. If I had a Wadia 861, I'd abandon most anything else, and focus on redesigning the output stages & power supplies to make it the spectacular player it could be.
hi, In your earlier reply you mentioned that Philips CDM 2 Pro LF is a drive which is not upto the mark!! Then how come many CD player manufacturer like Audio Note and others are still using these drives. Secondly, I would like to tell you that initially I have tried the external clock in Slave and Master mode. You cannot imagine how the sound became so soft and musical using AN DAC 4.1 and external clock. This slave and master configuration is not possible in the WAdia 861. But I can tell you that there is a lot difference in sound using external clock in Slave and Master mode between just using a external clocki
Hi, these are the observation:
1.in case of the old recorded CDR, (silver coloured)it cannot read the TOC and the front display shows blinking "----------" when the tray is opened the disc does not rotate
2. I have some black cd (CDR) where I have recorded some music, the drive could read the TOC but specially 1st track skips invariably
3. All the original has no problem.
4. It is taking much longer time to read the TOC compare to previous times. I could remember that the player could read the cd by max three blinks I pressure by 3 or 4 secs whereas now it is taking min of 5 secs and goes to 8 or 9 secs.
1.in case of the old recorded CDR, (silver coloured)it cannot read the TOC and the front display shows blinking "----------" when the tray is opened the disc does not rotate
2. I have some black cd (CDR) where I have recorded some music, the drive could read the TOC but specially 1st track skips invariably
3. All the original has no problem.
4. It is taking much longer time to read the TOC compare to previous times. I could remember that the player could read the cd by max three blinks I pressure by 3 or 4 secs whereas now it is taking min of 5 secs and goes to 8 or 9 secs.
It does sound like the new laser is just enough off-spec to be on the edge of range of the servo.
As for your 'how to proceed' request, you would have to ask someone else here who is specifically familiar with the unit you have.
As to why so many allegedly high-end makers use this Daisy Laser "Philips" cdm12-series garbage, I consider it a good indicator of who really is a high end maker. In other words, a maker who has avoided using the Daisy junk, IMO, is a good maker, assuming they don't use something even worse. Makers who use it deserve severe derision.
As for your 'how to proceed' request, you would have to ask someone else here who is specifically familiar with the unit you have.
As to why so many allegedly high-end makers use this Daisy Laser "Philips" cdm12-series garbage, I consider it a good indicator of who really is a high end maker. In other words, a maker who has avoided using the Daisy junk, IMO, is a good maker, assuming they don't use something even worse. Makers who use it deserve severe derision.
Hi,
Is anyone can help me to solve my Accuphase DP-80 transport problem which currently is unable to read any CD?
The transport was working fine in one of the day when I tried the new 75 ohm digital link cable to my DAC. Previously I was using the TOSlink cable and think of changing it to 75 ohm cable.
Hooked up both cables to my DAC and did an input selection on DAC, started to play a song from my transport. Everything sounds good from both TOSlink and 75 ohm cable.
Problem happened when I changed the CD, after loaded the second CD in the transport and started to play it. It no longer read the CD anymore and no track number was displayed on the front panel. After few seconds, the tray opened by itself and tried a few CDs but with the same result.
First thing come in my mind was the laser pick-up failure (Sony BU-1C) but sad to accept this because the pick-up was replaced less than a year.
I have a spare laser pick-up bought from eBay same as the first one and happy to replace it onto the transport. Shocked to me when the transport was still unable to read any CD and the tray opened after few seconds. The disc motor run for few seconds but stopped before CD was ejected.
Sad to see this result because both laser pick-ups were claimed to be new and bought from the same seller from eBbay.
Is anyone has the Accuphase DP-80 service manual? Hope to get some idea what is going to the transport from the manual or any idea what happened to the transport?
Sorry for the lengthy grandmother story here and thanks for reading.
Regards,
flyong
Hi flyong (and everyone)
How did you solve a problem?
Same problem on Accuphase DP-80L, but without tray opening and without motor working. Play and track numbers - zero, always.
regards
BU-1C
Maybe damaged locic IC - the IC responsible for "organizing" the steps of Load Eject /Toc read / putting laser diode on an so on.
Or broken switches that signal to the logic if tray is closed or open.
One very important thing about the BU-1C.
This transport was built to last forever! But the diode will fail some day. I did buy some BU-1 based player and observed laser power (after cleaning optics) at around 0.8V p-p.
Still good after 30 years but detoriated.
I am still looking for fellows to
explore the possibilities to replace an original (dead) laser diode from a BU-1C based transport with current diodes i.e. from Rohm.
Got some samples from them.
Many obstacles: Adapter has to be milled (fairly easy) astigmatism is a problem, alignment of the diode and diffraction grating in relation to the optics is also a big problem, APC has to modified.
Again, any input welcome. also check this post:
http://www.diyaudio.com/forums/digi...r-pickups-why-not-replacing-diode-only-4.html
There is so many of those good players around, would be a pity if they all became doorstoppers.
BTW, a misaligned diode or having no emission at all resulted in the same symptoms flyong described back in 2014.
New BU-1C off ebay always being stored ESD-safe? Unlikely. Maybe the replacement was dead as well. One easy trick to check emission is to film
the lens with a camera, the camera´s sensor makes infrared light visible.
All the best,
Sal
Maybe damaged locic IC - the IC responsible for "organizing" the steps of Load Eject /Toc read / putting laser diode on an so on.
Or broken switches that signal to the logic if tray is closed or open.
One very important thing about the BU-1C.
This transport was built to last forever! But the diode will fail some day. I did buy some BU-1 based player and observed laser power (after cleaning optics) at around 0.8V p-p.
Still good after 30 years but detoriated.
I am still looking for fellows to
explore the possibilities to replace an original (dead) laser diode from a BU-1C based transport with current diodes i.e. from Rohm.
Got some samples from them.
Many obstacles: Adapter has to be milled (fairly easy) astigmatism is a problem, alignment of the diode and diffraction grating in relation to the optics is also a big problem, APC has to modified.
Again, any input welcome. also check this post:
http://www.diyaudio.com/forums/digi...r-pickups-why-not-replacing-diode-only-4.html
There is so many of those good players around, would be a pity if they all became doorstoppers.
BTW, a misaligned diode or having no emission at all resulted in the same symptoms flyong described back in 2014.
New BU-1C off ebay always being stored ESD-safe? Unlikely. Maybe the replacement was dead as well. One easy trick to check emission is to film
the lens with a camera, the camera´s sensor makes infrared light visible.
All the best,
Sal
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