Omega Owners Forum

Omega Help Area => Omega Electrical and Audio Help => Topic started by: TheBoy on 21 June 2008, 09:44:02

Title: Laser Failures and CDRs
Post by: TheBoy on 21 June 2008, 09:44:02
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Also, do I remember reading on here that the CDR500 doesnt really like CDRs??

Correct - never designed to be compatable  :y

And now for the deluge that will now post saying that their unit may play them   >:(
I have noticed that Philips players in particular seem to be more prone to tired lasers after a lifetime of cdrs.  Is that your experience?

I have a Carin unit here that spits out all disks, and when I acquired it it had CDR in it.  Mrs TheBoys changer in the Rover (R770 HU, I think 036 changer) is Philips, and seems to be troublesome now :( (though it is 10yrs old, so can't grumble)

The changers in my Omegas (CDC2) seem to fair much better, but don't like cheap media, so Verbatim only.  My old 10 disc Kenwood from circa 1992 is still going strong, and has been used with CDRs since I got a writer mid nineties when they first came out (at 'sensible' prices (ie in the £100s)).

Is it a case that whoever supplies the lasers for the mechs used in early Kenwoods and the CDC2 are more suited than the Philips (who presumably use their own?) lasers for CDRs, and are able to focus on it better?

Or is my experience uncommon?
Title: CDRs and Laser Failure
Post by: Dave DND on 21 June 2008, 11:11:47
TB  
There is indeed a definate difference between makes and models as you righly point out. Philips often use thier own lasers, whilst Kenwood and Blaupunkt tend to generally favour the Sony lasers.

Looking over the past years between units that have played original discs only, and units that play CD`rs, the lifespan would appear to be

Original Discs use only:
Philips lasers approx 8-10 year lifespan - Sony lasers around 10-15 years.

Using CD`rs on a Non CDR designed player:
Philips lasers under 2 years - Sony lasers around 4 years.

Using CDR`s on a player Specifically designed to play CDR:
Not enough failures yet to spot any definative patterns.  (approx 5 years monitoring so far)

Generally speaking:
Aftermarket CD players introduced the ability to play CDR around 2001
Units before this date are NOT generally CD/RW compatable

OEM CD players introduced the ability to play CDR around 2005
Units before this date are NOT generally CD/RW compatable

OEM Navigation systems tend to bend the rules a little, as the data used is often in a more compressed format and the lasers are of a higher spec. These can often read CD`rs although the occasional duff read when first powered up from cold is usually more to do with condensation on / within the disc (they are not sealed at the edges like real discs) and not often suffer from laser failure.

Please note that these results are based purely on around 10,000+ cd players that we have seen over the last 15 years or so and are not part of any investigative experiment. Purely from data collated at time of repair submission or completed repair.

Certainly some patterns there to spark off some topic of conversation I think !!



Title: Re: CDRs and Laser Failure
Post by: TheBoy on 21 June 2008, 11:28:10
Firstly, want this to be a meaningful discussion, rather than a 'it works for me' slanging match, so can everyone bear that in mind before posting.  Dave DND has posted his extensive experience above :y

Title: Re: CDRs and Laser Failure
Post by: TheBoy on 21 June 2008, 11:31:42
Dave DND - my own experience suggests I get longer out of my Changers than average would suggest.

The (now dying) Philips changer in the Rover as probably only ever seen 1 or 2 pressed CDs, and is now 10yrs old.  The (still going strong) CDC2 in my MV6 has only had CDRs in the 4.5yrs I've had it (just replaced for another CDC2, but due to changing to crt700 HU).

Am I lucky, or is it that I only use premium disks (Verbatim) a factor?  It seems I have had the expected life out of the Rover's Philips changer, even though purely using CDRs instead of pressed disks  :-/


I should add, none of my cd changers will play CDRWs, so we're talking purely CDR here
Title: Re: CDRs and Laser Failure
Post by: Dave DND on 21 June 2008, 11:50:05
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my own experience suggests I get longer out of my Changers than average would suggest

Remember that my findings will also rely heavily on "average" car mileage and vehicle usage. If you use a car every day, all day, then your unit may wear out faster than if only used for Sunday best. I never thought to add mileage to vehicles when booking cars in all those years ago.

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Am I lucky, or is it that I only use premium disks (Verbatim) a factor?

A number of people have commented on the use of Good brands, but that does not mean that the format of the media has altered. The lasers are struggling to see computer recorded data that is a lot smaller that audio data. Some comments have previously been made about the new Sony Audio recordable discs, but as yet my findings are inconclusive at this early stage.

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I should add, none of my cd changers will play CDRWs, so we're talking purely CDR here

I haven`t differentiated between the formats here. My findings are based on either shop bought pre-recorded discs, or self recorded discs, whether they be CDR / CDRW / CDV / VCD or anything else meant for your home computer.

Title: Re: CDRs and Laser Failure
Post by: TheBoy on 21 June 2008, 12:02:37
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my own experience suggests I get longer out of my Changers than average would suggest

Remember that my findings will also rely heavily on "average" car mileage and vehicle usage. If you use a car every day, all day, then your unit may wear out faster than if only used for Sunday best. I never thought to add mileage to vehicles when booking cars in all those years ago.
My cars, as an average, have their CD players on for 1-2hrs, 7 days a week...   ...obviously long runs will be more, but some days we don't use the cars...
Title: Re: Laser Failures and CDRs
Post by: JueV6 on 21 June 2008, 16:08:33
Dave / TB

I have a carin unit in my elite and as TB say, it spits all disks out. (no Disk in it when i got the car). I've taken teh cover off and watched as a cd loads and the disk won't / doesn't spin. It then spits the disk.

Although that doesn't seem to be a laser issue, have either of you any idea's
Title: Re: Laser Failures and CDRs
Post by: Dave DND on 21 June 2008, 16:26:35
That can often be a sign that the laser is too weak to see the disc, or that either the disc or the lens is dirty and needs cleaning.

Try a different disc, audio or computer and see if the disc "spins" briefly before being spat out - if it does, then sounds like a laser failure.
Title: Re: Laser Failures and CDRs
Post by: tmx on 21 June 2008, 16:58:36
my mrs rover cdc didnt work when we bought it its a 97 R reg 414 Si so i ripped it out and put in my old chavmaster Alpine hu w disc changer this has only ever had CDRs in and is now around 6 years old no problems with it yet! :y

mv6 tho  >:(

my mv6s CCRT changer i think is jafferd everytime i go over a bump it stops working makes funny speaker noises and decides theres an error with the cd even with pressed cds

however itll play  whats ever in slot 5 perfectly ok

any ideas dave? looks filthy and dusty inside and its been prone to damp as the casing is alittle rusted come out of a scrap elite
Title: Re: Laser Failures and CDRs
Post by: Mr Skrunts on 21 June 2008, 17:26:21
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my mrs rover cdc didnt work when we bought it its a 97 R reg 414 Si so i ripped it out and put in my old chavmaster Alpine hu w disc changer this has only ever had CDRs in and is now around 6 years old no problems with it yet! :y

mv6 tho  >:(

my mv6s CCRT changer i think is jafferd everytime i go over a bump it stops working makes funny speaker noises and decides theres an error with the cd even with pressed cds

however itll play  whats ever in slot 5 perfectly ok

any ideas dave? looks filthy and dusty inside and its been prone to damp as the casing is alittle rusted come out of a scrap elite

Sounds like a dust/dirt issue there, especialy when it plays disk 5 ok, have you checked the caddy for damage?
Title: Re: Laser Failures and CDRs
Post by: tmx on 21 June 2008, 18:08:17
yep checked caddy ill get a CD cleaner disc
Title: Re: Laser Failures and CDRs
Post by: Kevin Wood on 21 June 2008, 19:51:35
What is the failure mode, normally? Laser diode itself kaputt or the focus coils?

Kevin
Title: Re: Laser Failures and CDRs
Post by: Dave DND on 21 June 2008, 19:59:56
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Sounds like a dust/dirt issue there, especialy when it plays disk 5 ok, have you checked the caddy for damage?

Sounds like a dust / dirt sissue to me as well, although I would tend to remove the covers and clean the lens manually - gently with a cotton bud - NO CHEMICALS !!

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What is the failure mode, normally? Laser diode itself kaputt or the focus coils?

Mixture of both really, but the focus coils tend to be a sign that the laser power will give up shortly afterwards. Not that it really matters, the focus coild cannot be changed independantly on most of the In Car Stuff - laser module failure is Laser module failure !!
Title: Re: Laser Failures and CDRs
Post by: TheBoy on 22 June 2008, 10:31:08
And chances of getting a new laser for my philips changer thats on its way out (036 is changer model)
Title: Re: Laser Failures and CDRs
Post by: Dave DND on 22 June 2008, 10:45:17
Quite a few of the Philips lasers are still available, although obviously not from Philips!

Pattern ones are readily available also -

What part number are you trying to find? (written on label of laser)
Title: Re: Laser Failures and CDRs
Post by: TheBoy on 22 June 2008, 10:49:15
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Quite a few of the Philips lasers are still available, although obviously not from Philips!

Pattern ones are readily available also -

What part number are you trying to find? (written on label of laser)
I'll hook it apart later :y.  Is it easy enough to change?
Title: Re: Laser Failures and CDRs
Post by: Dave DND on 22 June 2008, 11:29:26
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Is it easy enough to change?

Without knowing your technical capabilities - difficult one to answer.

Not something a novice should tackle though  :(
Title: Re: Laser Failures and CDRs
Post by: TheBoy on 22 June 2008, 19:43:36
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Is it easy enough to change?

Without knowing your technical capabilities - difficult one to answer.

Not something a novice should tackle though  :(
I guess when I take it apart, I'll be able to tell difficulty level then...
Title: Re: Laser Failures and CDRs
Post by: Marks DTM Calib on 22 June 2008, 21:16:43
Dave, I assume the modern integrated pickup assemblies arrive with the laser power pre-set?

Do they still short out the BFD contacts to protect them from static during transit?
Title: Re: Laser Failures and CDRs
Post by: Dave DND on 22 June 2008, 21:30:42
Yes, the contacts are soldered during transit to prevent static problems.

The lasers arrive preset from factory, but may require tweaking in circuit to give a clean "S-Curve" with no clipping.

Modern sets often do this automatically, or at least after a few calibration procedures have been done, whereas the older sets will need a bit of playing with the old scope connected I`m afraid.
Title: Re: Laser Failures and CDRs
Post by: tmx on 23 June 2008, 00:05:58
tried cleaning my CDC 2 CCRT editions laser and it worked ok for cd1 & 2 and now its gone to pot again  but this time its sharp static throught the whole cd

playing brand new unused cds

my question is i have a CDC 2 CCR 600 edition can i swap the lasers and disc changer mechanism and swap it with my paperweight cdc2?
Title: Re: Laser Failures and CDRs
Post by: Dave DND on 23 June 2008, 08:57:04
Providing that they are the same part number, swapping the lasers is a lot of work and possibly not worth the time taken to do this with a second hand one that is also near the end of its life.

If however, you are intent on trying something and have 2 CDC2 changers that are not immidiately protocol compatable with your head unit, its probably easier to change over the main circuit board from one to the other as this is where the protocol chips are located and it should(?) then power up on your existing head unit, but using the entire mechanism of the other changer.
Title: Re: Laser Failures and CDRs
Post by: davlad22 on 24 June 2008, 16:12:20
If you do insist on using CDr's in your vehicles, and many people do due to reasons of theft and damage to discs etc. (as well as home audio equipment) my experience of pressing some several thousand discs has found a combination that works most reliably. As TB remarked, the key is good media. Verbatim discs are good but I tend to favour 'Imation' discs. These have proved most reliable for myself but also burned in tandem with a good writer.

CD writers are so cheap, the ones I prefer are made by Pioneer and have achieved perfect results everytime through Nero, some of which are a good number of years old. We have managed to achieve around 99% success when using this disc/write method.

The other important issues with CDr's is CD labels. The heat generated in a head-unit can cause the labels to peel off and land you in sticky (no pun intended!) territory. My advice would be not to use cheap labels and not to use thick labels, they can also cause balance issues with the disc, better not to use labels at all.
Title: Re: Laser Failures and CDRs
Post by: tmx on 24 June 2008, 16:55:07
yes i have a pioneer CDRW & a panasonic toughbook cdrw i use sony media just out of personal choice!

dave thanks for the sugestion ill just swap the control boards over and see what happens :D
Title: Re: Laser Failures and CDRs
Post by: TheBoy on 29 June 2008, 18:27:06
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If you do insist on using CDr's in your vehicles, and many people do due to reasons of theft and damage to discs etc. (as well as home audio equipment) my experience of pressing some several thousand discs has found a combination that works most reliably. As TB remarked, the key is good media. Verbatim discs are good but I tend to favour 'Imation' discs. These have proved most reliable for myself but also burned in tandem with a good writer.

CD writers are so cheap, the ones I prefer are made by Pioneer and have achieved perfect results everytime through Nero, some of which are a good number of years old. We have managed to achieve around 99% success when using this disc/write method.

The other important issues with CDr's is CD labels. The heat generated in a head-unit can cause the labels to peel off and land you in sticky (no pun intended!) territory. My advice would be not to use cheap labels and not to use thick labels, they can also cause balance issues with the disc, better not to use labels at all.
Had no end of hassle with Imation.  Tend to stick to pioneer/nec writers.

doesn't affect fact it is putting more strain on laser though.