I know that this thread is over two years old but it deals with the exact problem I am having. Firstly, am not a technician, so I cannot diagnose or repair my own unit. I originally bought my DCM 390 on ebay and it arrived with problems. It was not reading CDs. It got fixed but not too long afterward the problem cropped up again. I ordered a whole new KSM 213 CCM mechanism to replace the KSM CLCM mechanism that was installed. This has worked for almost two years and now the machine is having problems to read CDs once more. I am also seeing all these bad reviews about the longivety of Denon's CD players and its not very reassuring at this point. My question is, Can I replace the KSM 213 CCM mech with a later model like the KSS 213 Q? I really find it hard to believe that I would have to change a laser pickup assembly every 1.5 - 2 years! Can anyone help?
Bad lasers?
I also read through this old thread. I'm sitting with a much newer DCD-F107 that about two months after being firmware updated by Denon started having problems reading discs. It's "naturally" just out of warranty.
Typically, when a disc is inserted the dics spins a few rounds and the player reports "No Disc" or "00Tr 00:00". However, in those rare cases where it does get the TOC read it will play flawlessly. I was initially thinking it was a bad laser (Sony made a bunch of those that died after a year or two). Now I'm just puzzled. If anyone that stumbles over this has a service manual for the Denon DCD-F107 or knowledge of an actual common laser problem I'd love to hear about it. (Building on the experience of the Sonys, it makes no sense to put in a new, crappy laser if it's the same issue. But darn I hate to throw out equipment!)
I also read through this old thread. I'm sitting with a much newer DCD-F107 that about two months after being firmware updated by Denon started having problems reading discs. It's "naturally" just out of warranty.
Typically, when a disc is inserted the dics spins a few rounds and the player reports "No Disc" or "00Tr 00:00". However, in those rare cases where it does get the TOC read it will play flawlessly. I was initially thinking it was a bad laser (Sony made a bunch of those that died after a year or two). Now I'm just puzzled. If anyone that stumbles over this has a service manual for the Denon DCD-F107 or knowledge of an actual common laser problem I'd love to hear about it. (Building on the experience of the Sonys, it makes no sense to put in a new, crappy laser if it's the same issue. But darn I hate to throw out equipment!)
Hi
I do realize the last post in this thread was about 10 years ago, but with a bit of luck ...
So I have a DCM-340 that skips back and forth. However, it seems to be only about 2 min of the first song on a CD, otherwise stable playing what I have noticed so far.
I have run it in Heat Run mode. It does not show any error codes. Also it seems to run much more stable in Heat Run mode, less skipping and if skipping occurs only 1-2 seconds, while in normal operation it can skip 1-2 minutes forward or backward and much more frequent.
Music sounds ok when playing.
Any suggestions what issues to look for?
Thanks!
I do realize the last post in this thread was about 10 years ago, but with a bit of luck ...
So I have a DCM-340 that skips back and forth. However, it seems to be only about 2 min of the first song on a CD, otherwise stable playing what I have noticed so far.
I have run it in Heat Run mode. It does not show any error codes. Also it seems to run much more stable in Heat Run mode, less skipping and if skipping occurs only 1-2 seconds, while in normal operation it can skip 1-2 minutes forward or backward and much more frequent.
Music sounds ok when playing.
Any suggestions what issues to look for?
Thanks!
Hi Zwill,
Time for some reality I think. Denon machines are very, very reliable. They use Sony CD transports for starters. So let's ignore yapping from non-technicians and people who have no idea what they are talking about!
You used a substitute laser / mechanism that is manufactured more cheaply. Strike one.
You did not align the laser, obviously because you don't know how and don't have the equipment. Okay, but you declined to have someone who actually knows how to service these things. Strike two.
Firstly, someone who actually understands and has the experience and equipment to align one of these is more rare these days. You have to find a real skilled technician. One thing people don't understand is that the alignment affects sound quality. Just because it plays does not mean it is delivering the best sound quality! Just because something works doesn't mean it was serviced properly either!
I have been a professional service tech since the late 1970's. Unfortunately the last generation of well trained techs, there isn't any coming up because the good ones went to industry. I trained the last tech in the late 1990's, sold my shop in 1998. Almost every half decent tech I knew or meet works from home today. Now, what I see coming in is mostly equipment hacked by people who believe they are great techs - but shouldn't be allowed to touch a soldering iron. I'm seeing the use of fake parts and poor substitute parts, and a lack of setting anything up well. Even amplifiers are being destroyed, never mind a CD player! Think of aligning a tuner - that's pretty grim these days.
So before knocking a very good product like your Denon, look at how you have treated it. I was authorized warranty for Denon and many other brands including Revox, Nakamichi, Marantz, Carver Cyrus and many others that also include recording studio equipment manufacturers. I use CD players and streamers, tuner and turntables at home. Properly serviced they are wonderful. I even use cassette decks (Nak CR-5)! If you maintain your equipment it will provide you with long service and high quality performance. If you aren't prepared to do that, then may as well buy some garbage and replace it whenever it hiccups. Of course you will never have great performance, but that is your decision.
So why not start by using the original parts and get it into the care of a real technician who will recreate the Denon you desire?
Time for some reality I think. Denon machines are very, very reliable. They use Sony CD transports for starters. So let's ignore yapping from non-technicians and people who have no idea what they are talking about!
You used a substitute laser / mechanism that is manufactured more cheaply. Strike one.
You did not align the laser, obviously because you don't know how and don't have the equipment. Okay, but you declined to have someone who actually knows how to service these things. Strike two.
Firstly, someone who actually understands and has the experience and equipment to align one of these is more rare these days. You have to find a real skilled technician. One thing people don't understand is that the alignment affects sound quality. Just because it plays does not mean it is delivering the best sound quality! Just because something works doesn't mean it was serviced properly either!
I have been a professional service tech since the late 1970's. Unfortunately the last generation of well trained techs, there isn't any coming up because the good ones went to industry. I trained the last tech in the late 1990's, sold my shop in 1998. Almost every half decent tech I knew or meet works from home today. Now, what I see coming in is mostly equipment hacked by people who believe they are great techs - but shouldn't be allowed to touch a soldering iron. I'm seeing the use of fake parts and poor substitute parts, and a lack of setting anything up well. Even amplifiers are being destroyed, never mind a CD player! Think of aligning a tuner - that's pretty grim these days.
So before knocking a very good product like your Denon, look at how you have treated it. I was authorized warranty for Denon and many other brands including Revox, Nakamichi, Marantz, Carver Cyrus and many others that also include recording studio equipment manufacturers. I use CD players and streamers, tuner and turntables at home. Properly serviced they are wonderful. I even use cassette decks (Nak CR-5)! If you maintain your equipment it will provide you with long service and high quality performance. If you aren't prepared to do that, then may as well buy some garbage and replace it whenever it hiccups. Of course you will never have great performance, but that is your decision.
So why not start by using the original parts and get it into the care of a real technician who will recreate the Denon you desire?
dreamth,
Please don't spread moronic advice from obviously badly informed sources. You are not helping anyone, and actually doing a lot of harm. One post can be responsible for thousands of dollars of damage to people's equipment when others blindly follow your advice. We have got to be a little more responsible when placing our fingers on a keyboard!
Really? Who told you something so incredibly stupid!!! No. You can't do that. The laser will run hotter, already down in efficiency if it was the problem to start with. At some point it will suddenly stop working never to operate again because you burned it out. There is no warning. If increasing the laser current, the "technician" has drastically shortened it's life and ripped the customer off.
Why? What is that supposed to prove? Why not actually check the alignment properly? While you're at it, you would check the laser current and compare that to the value on the head. You're allowed a maximum 10% increase before the head is officially considered bad. We also measure the laser power output (yes, I have a meter for that).
Please don't spread moronic advice from obviously badly informed sources. You are not helping anyone, and actually doing a lot of harm. One post can be responsible for thousands of dollars of damage to people's equipment when others blindly follow your advice. We have got to be a little more responsible when placing our fingers on a keyboard!
You answered the wrong guy...read the posting dates!
Today's Sun-day! Are we allowed to be moronic while bathing in the Sun light on Sunday?
By the way we do that on a regular basis with old cd players cause they have no value anyway after 30 years of use.A decade ago I used to repair , sercice and callibrate10 k...2 million bucks diode, NdYag, HeNe,Exciplex ,and CO2 Coherent's and lituanian laser units and I never had all the tools to do it properly, but our clients were the Universities, the Customs, the Pharma industry, the Army and the small silicon waffer prototyping companies and I can tell you for sure I never spent useful time with useless, outdated equipment unless it paid my wages!
What I recommended is a very quick method of finding if an old cd player is worth fixing.
What I recommended is a very quick method of finding if an old cd player is worth fixing.
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Hi Thomasx,
Okay, so if heat run mode runs you probably have a worn bearing in the disc motor (replace the motor if this is true). The other thing that can happen is the laser gets stuck on the slide. What you want to do is monitor the slid motor output, a scope in DC coupling mode is the easiest. You'll see the drive increase in one polarity, then it should quickly drop towards zero when the slide moves. If that voltage goes to the other polarity it means the laser overshot the point and this means it got hung up slightly.
Keep in mind the disc spins faster in the middle, so sled movement is more frequent. But bearing vibration is also greater. To test carefully I remove the transport and run the disc motor at low voltage through a resistor and slowly rotate the mechanism vertically and listen. At some points you can hear the motor knocking and may even feel the vibrations. In some cases a winding may go dead or short and you can use an oscilloscope to look for "flat spots" in the waveform across the motor. If this was a problem the CD would probably fail to spin in your case - so not an issue.
At this point it would be normal to check the eye pattern with a 'scope (labeled RF sometimes) with a scope. It should be clear and stable. If it is low and "fuzzY, either the head is toast, or the disc table has been moved to the wrong height. This is a critical distance and needs to be set carefully. Also measure the voltage across the laser current sense resistor, calculate the current. Compare that to the current marked on the head. Again, you're allowed 10% rise maximum before condemning the head.
These steps are correct and will always lead you to the right answer. You can get other odd faults and this is where experience can really help. But get the basics in line first.
Is it worth installing the correct head and motor? Yes, absolutely, because the CD mech is now basically brand new. I have the required jigs, and any Denon tech should also have them. If you change the head you absolutely must align it as well.
Okay, so if heat run mode runs you probably have a worn bearing in the disc motor (replace the motor if this is true). The other thing that can happen is the laser gets stuck on the slide. What you want to do is monitor the slid motor output, a scope in DC coupling mode is the easiest. You'll see the drive increase in one polarity, then it should quickly drop towards zero when the slide moves. If that voltage goes to the other polarity it means the laser overshot the point and this means it got hung up slightly.
Keep in mind the disc spins faster in the middle, so sled movement is more frequent. But bearing vibration is also greater. To test carefully I remove the transport and run the disc motor at low voltage through a resistor and slowly rotate the mechanism vertically and listen. At some points you can hear the motor knocking and may even feel the vibrations. In some cases a winding may go dead or short and you can use an oscilloscope to look for "flat spots" in the waveform across the motor. If this was a problem the CD would probably fail to spin in your case - so not an issue.
At this point it would be normal to check the eye pattern with a 'scope (labeled RF sometimes) with a scope. It should be clear and stable. If it is low and "fuzzY, either the head is toast, or the disc table has been moved to the wrong height. This is a critical distance and needs to be set carefully. Also measure the voltage across the laser current sense resistor, calculate the current. Compare that to the current marked on the head. Again, you're allowed 10% rise maximum before condemning the head.
These steps are correct and will always lead you to the right answer. You can get other odd faults and this is where experience can really help. But get the basics in line first.
Is it worth installing the correct head and motor? Yes, absolutely, because the CD mech is now basically brand new. I have the required jigs, and any Denon tech should also have them. If you change the head you absolutely must align it as well.