reclocking digital data

we know jitter increase for copy cdr
is reclocking digital data (like meridian G08 cdplayer) will increase sound quality in comparison by general cdplayers without reclocking (with copy cdr)?

 

Do we? Can't see how it could.

 

see yamaha or teac writers review for jitter in pc review magazines

 

Jitter doesn't increase when you copy to CDR. In fact jitter doesn't exist on CDs or CDRs - it's only something that exists during the D->A conversion or in the transmission of digital data.

Michael.

 

I don't agree you michaelab

 

Then you need to accept the fact that you are wrong (and Michael is right).

The channel code that is read off the disc does not pass directly to the dac. It's buffered before it passes to the CIRC error correction block.

The flow of data into the buffer is irregular mostly because of fluctautions of the rotation of the disc (motor speed variations). The buffer occupancy drives a servo that controls the disc rotation, mediating the flow of data into the buffer.

Data is clocked out of the buffer precisely.

Jitter, in common parlance, has to do with DAC timing and is a completely different issue which has nothing to do with the physical properties of the disc.

MF

 

There will be some jitter type errors physically recorded on the original CD, the result of timing errors of the digitising clock. Copying this data from one CD to another won't change this, and as said above jitter on the signal transfer is irrelevant. You're making a bit for bit copy, like copying a computer data file; timing of data transfer (and thus jitter) only matters when the data is converted to sound as a real time process.

Reclocking can do nothing for the jitter recorded on the original CD (or a CDR).

 

I think copy cdr are different from original cd but about circ error checking i didnot know in transport signal will be reclocked.
see http://www.cdrinfo.com/Sections/Reviews/Specific.aspx?ArticleId=7380&PageId=2
there is information about writing hardware

 

Interesting to see those results Amir. The graphs are of 'jitter' of the physical pits and lands on the disc which as I think you now see is not the same thing as the jitter of the digital signal you end up with. The values of this spatial jitter plotted are from 22-32ns, by contrast the jitter on output digital signals from CD transports are more like a few hundred ps, so about 100 times smaller (for the reason oedipus descrebed).