Hard-disk vs cd-player

[DragonMaster]

What is doing iTunes???????

You answered:

Anyway

What would be interesting is to know the exact details of how the powerbook plays CDs via the optical out.

Does it read at 1x and the drive itself encodes the SPDIF or does it read raw data into main memory, buffer and then play out the samples in the same way it plays a WAV?

Yes but it's still better with another cdplayer feeding the same dac...

If the CD is player thru the CD player optical out(Normal playback), there is more jitter/errors than by playing using DAE (Reading the RAW data from the data port like with the HDD). The only problem is that most DAE players aren't re-reading errors like a CD ripper or CDReader plugin would do.

An easy check to see if you read the CDs using DAE is to see if there's a separate connector other than power and data going to the CD-ROM. But since you have a powerbook, it might not be really easy to see.

 

[hugobors]

And you are using iTunes (i.e compressed audio?)?

I'm using itunes but the CD was ripped in WAV format.

There is no doubt in my mind that the audio data is most reliably read when using an excellent computer drive such as Plextor Premium CD Burner and one has enough time to allow for re-reads which the drive will do without addtional software. It is probably better than even the most expensive CD players for this bit extraction even if it reads without the possibility for re-reads.

So do you think that using a good computer cd player in stand alone with spdif out as transport is good????? Will it do re-reads in this configuration or re-reads must be done by software????????

 

[DragonMaster]

So do you think that using a good computer cd player in stand alone with spdif out as transport is good????? Will it do re-reads in this configuration or re-reads must be done by software????????

I don't know for the Plextor, but usually, the CD player feature on CD-ROMs (for both SPDIF out and analog outputs) are really primitive and have lots of interference. Most of them stop working correctly with age. I suppose that the pickup gets dirty, but often even cleaning up doesn't work.

Unless there are some really advanced cd-rom units, re-read is only done by -some- software using digital audio extraction thru the IDE port. Some just read the data and use "error correction" which replaces the read errors with zeros(No sound).(Most players) Some players and CD rippers are re-reading, they are also spinning the CD faster than 2x or 4x to do this correctly.

If you can have a lot of time to wait, then you could wait for the project in the topic "Digital audio from IDE" to be finished. It's a CD player based on a computer CD-ROM.