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Essential technical specs for cd transport ONLY

Yuhasz01

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What are the essential technical specs for evaluating a cd transport Only? Goal is to play Redbook cd disks.
I imagine just insuring bit perfect capture of data can be done with any of three used mechanisms: a slot loader, sliding tray loader, or top down mechanism(ie CDM4). Are they all technically accurate and no real differences, like DACs today? There job is to read and capture a digital signal and pass along to a DAC.
 

Doodski

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One needs a 100MHz or better oscilloscope for viewing the RF eye pattern and the various servo adjustments that are usually available in the CD player. What CD player are you going to be using?
 

Doodski

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I NEVER heard ANY defects from a CD player unless the CD was damaged/defective.
I've seen the oddball rare case where the DSP, RF amp or other part goes wonky and the CD player outputs poor sound quality and does not fail completely. It was fairly common in Sony gear back when a CD player was a thing.
 

Kal Rubinson

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I've seen the oddball rare case where the DSP, RF amp or other part goes wonky and the CD player outputs poor sound quality and does not fail completely. It was fairly common in Sony gear back when a CD player was a thing.
Didn't the OP say "cd transport Only?"
 

Doodski

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Didn't the OP say "cd transport Only?"
True he did. I conflated in my mind multiple CD mechanisms, some with RF DSP boards mounted to the mechanism and some on a mainboard. My bad for mentioning Sony home audio CD players but the car audio gear has RF and DSP on the mechanism and they would output hashy sounding audio too when the RF amp or DSP was wonky. So I was partly in error and partly not although I never explained myself properly. The answer from me for the OP is that CD players can output imperfect bitstream and imperfect audio too. By looking at the RF eye pattern one can see the jitter and the dropouts in the bitstream and that carries downstream to the digital output if the error is too large.
 

Harmonie

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I still keep my EAD T-1000 CD transport because I purchased it .... 26 years ago.
Otherwise I wouldn't worry as @q3cpma said.
 
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Yuhasz01

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I can't imagine a good excuse for really worrying about this and not ripping your CDs to get rid of all those problems inherent to hardware based, real time CD playback.
Ripping cd to digital files degrades fidelity.

I buy a lot of cheap cds from people like you, thanks.
 

kchap

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Ripping cd to digital files degrades fidelity.
Could you expand on that? I'm not convinced.

I'd be interested any recommendations for CD readers that are better at ripping. Especially difficult CDs. I have a few CDs that failed ripping even though there seemed to be little damage to the surface.
 

MarcosCh

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Could you expand on that? I'm not convinced.

I'd be interested any recommendations for CD readers that are better at ripping. Especially difficult CDs. I have a few CDs that failed ripping even though there seemed to be little damage to the surface.
Maybe copy protected. You can check if they have the "compact disc" logo. If not, they are copy protected.
Getting a second cheap optical unit is a good idea, in my case it could read 90% of the cds the first unit couldn't
 

kchap

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Maybe copy protected. You can check if they have the "compact disc" logo. If not, they are copy protected.
Getting a second cheap optical unit is a good idea, in my case it could read 90% of the cds the first unit couldn't
I have a pioneer CD/DVD reader which does a good job but a few CDs generate un-correctable errors. I was wondering if there are CD readers that are better at dealing which scratches than others or have superior tracking abilities.
 

MarcosCh

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I have a pioneer CD/DVD reader which does a good job but a few CDs generate un-correctable errors. I was wondering if there are CD readers that are better at dealing which scratches than others or have superior tracking abilities.
If they are scratches, no idea, back in the day some CD players were promoted as being better at that, but can't recommend you any (maybe @restorer-john knows) But have you checked they have the red book logo?
 
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Doodski

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I have a pioneer CD/DVD reader which does a good job but a few CDs generate un-correctable errors. I was wondering if there are CD readers that are better at dealing which scratches than others or have superior tracking abilities.
Yes, some CD players have better tracking ability. Back to the RF eye pattern and the servo adjustments for tuning the response of the controls of the CD player and seeing the focal characteristics of each disc as it is playing.
 

kchap

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Yes, some CD players have better tracking ability. Back to the RF eye pattern and the servo adjustments for tuning the response of the controls of the CD player and seeing the focal characteristics of each disc as it is playing.
I'm not sure if sure if I'm brave enough to take it on but, are there web sites I can go to to learn about the world of DIY CD transport repair and adjustment.
 

Doodski

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Get the service manual for the model of CD player that you want to take to task. In the service manual there will be service procedures for alignment/calibration and RF eye pattern characteristics. You need a 100MHz scope or greater and use the ground from the PCB for the scope probe ground. Sony service manuals are very good to work with.
 

kchap

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Katji

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[...]
I'd be interested any recommendations for CD readers that are better at ripping. Especially difficult CDs. I have a few CDs that failed ripping even though there seemed to be little damage to the surface.
I have a pioneer CD/DVD reader which does a good job but a few CDs generate un-correctable errors. I was wondering if there are CD readers that are better at dealing which scratches than others or have superior tracking abilities.
EAC (ripping program) tests CD drive and sets some configuration/parameters accordingly, the read offset correction. iirc...it does some reference lookup, based on the type or some CD hardware identifier. (Sorry, vague, it's been a while.) Probably dbPoweramp does it too.
And re-read / test/verify.
I wouldn't use anything else.

Not that that helps you if you want to play CDs though.

I have some or other CD writer...but EAC seemed to think that my laptop CD drive was better. - Slightly, somewhat.
 
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