The perfect wave transport from PS Audio

hhmmmmmm

Excellent sales pitch..

Err doesn't every CD player worth its name have a reclocker and some form of buffering off solid state memory? Whats so special in this one then?

What about the data that is lost while reading the CD itself?

The only special thing about this player seems to be the fact that it has I2S output which very few transports do.

I think it uses an HDMI cable for I2S...and it is a special non standard HDMI so you needd to have PS audios transport, cable and DAC for I2s. thank god the power cables are standard IEC

this is different in the sense that it "rips" from the disc and puts the entire song into a SS memory and then plays it..

I2S is a signal that cannot be transmitted beyond a few inches. If you need to (transmit I2S over a few feet)... then use the SPDIF. Else you need your properiraty arrangement to do the same...like Zanden and now PS audio. Honestly, i do not see this to be of any significant advantage.

A lot of these theory of buffering in memory etc., does not really help with PCM because of the nature of the format itself. Hence, It is not correct to assume..what is good for formats like "WAV" will be good for PCM as well. PCM is a very different format. Do read on the net....you will get some idea.

Once you have a good idea of PCM and also about how I2S/SPDIF actually works....listen to this Video again.

http://en.wikipedia.org/wiki/Pulse-code_modulation
http://en.wikipedia.org/wiki/Red_Book_(audio_CD_standard)

A quick google returned this..

http://en.wikipedia.org/wiki/Pulse-code_modulation

From the above link, you can understand how the data on a red-book CD should be interpreted...there are no obvisous 1's and 0's like in computer audio-file formats like WAV, MP3, etc.,

Also, you could verify what i'm saying form the below link..

http://en.wikipedia.org/wiki/Red_Book_(audio_CD_standard)

The above has been my understanding as well ie about the Redbook being in "Words" and not bits.. which need to be interpreted with utilisation of the Reed Solomon Error correction.

An interesting (and heated) discussion http://www.audioasylum.com/cgi/vt.mpl?f=digital&m=131391here

sivat schrieb:

I2S is a signal that cannot be transmitted beyond a few inches. If you need to (transmit I2S over a few feet)... then use the SPDIF. .

Siva any reason for this ?
ie is it a problem of the Format that is open to some sort of distortion or loss of synchronisation during longer tramnsmission ?

Arj schrieb:

The above has been my understanding as well ie about the Redbook being in "Words" and not bits.. which need to be interpreted with utilisation of the Reed Solomon Error correction. An interesting (and heated) discussion http://www.audioasylum.com/cgi/vt.mpl?f=digital&m=131391here

No Arj, it is not the content that matters. But how the content is retrieved. Unlike in a WAV file, where the 1's and 0's are guaranteed to be correct....the data from Redbook CD is retrieved through a sampling algorithm.

This is the part that is most error prone and requires excellent mechanial and electrical isolation for the CD transport to a good job. If you would have observed "time" is a factor in the sampling process...so the "memory storage" is really not of much help at all in reducing Jitter.

This is exactly the reason why companies like Esoteric, Philips, Sanyo have spent lots of money in developing good transport modules (VRDS, CD-PRO2, etc.,)

This is also the reason why filters came into existence. But nothing can compensate a good "transport module" to begin with....rest are all hypothesis and not actual facts.

Arj schrieb:

sivat schrieb: I2S is a signal that cannot be transmitted beyond a few inches. If you need to (transmit I2S over a few feet)... then use the SPDIF. . Siva any reason for this ? ie is it a problem of the Format that is open to some sort of distortion or loss of synchronisation during longer tramnsmission ?

If you need to transmit data over a cable through some distance it requires a proper design. You cannot just transmist any form of data over any length of cable.

So the problem is not really the 'content' of I2S format or the format itself, but the physical limitations that one needs to over-come for transmitting data over long lengths of cable.

This is also the reason why it is recommend to use transformers for driving long lengths of SPDIF cable.

sivat schrieb:

Arj schrieb: The above has been my understanding as well ie about the Redbook being in "Words" and not bits.. which need to be interpreted with utilisation of the Reed Solomon Error correction. An interesting (and heated) discussion http://www.audioasylum.com/cgi/vt.mpl?f=digital&m=131391here No Arj, it is not the content that matters. But how the content is retrieved. Unlike in a WAV file, where the 1's and 0's are guaranteed to be correct....the data from Redbook CD is retrieved through a sampling algorithm. This is the part that is most error prone and requires excellent mechanial and electrical isolation for the CD transport to a good job. If you would have observed "time" is a factor in the sampling process...so the "memory storage" is really not of much help at all in reducing Jitter. This is exactly the reason why companies like Esoteric, Philips, Sanyo have spent lots of money in developing good transport modules (VRDS, CD-PRO2, etc.,) This is also the reason why filters came into existence. But nothing can compensate a good "transport module" to begin with....rest are all hypothesis and not actual facts.

So it all depends on the quality of the mechanical transport which reads the cd. Whether it is stored in memory and send via i2s or send directly via spdif to a DAC doesn't really matter.
The logic is that the error originates while the disc is being read initially. What happens after the disc is read is immaterial.

So it all depends on the quality of the mechanical transport which reads the cd. Whether it is stored in memory and send via i2s or send directly via spdif to a DAC doesn't really matter. The logic is that the error originates while the disc is being read initially. What happens after the disc is read is immaterial.

IMHO, everything else too DOES matter.

But if garbage is made of the data on the CD... its GIGO ( Garbage In Garbage Out )

Amnut

I am with you on this. Every stage matters, perhaps to different degrees but they all matter.

Manek

Folks,

My discussion was limited to getting the 1's and 0's correct fromm a CD. What i referred to as "rest of ..." was the predictive algoritms that are employed in some of the filters...including oversampling, upsampling, etc., Everyone know the application of such predictive algoritm do not result in correct output at all scenarios.

Ofcouse, other stages are important. But the idea behind this discussion was to bring to light some important aspect of the PCB/Redbook format that is being taken for granted, with the advent of media servers.

The idea was to emphazie on the need for a good quality laser-picup and associated mech and electrical aspects. This should be the focus of a good transport....atleast in my opinon.

Peace

Regards
Siva.

HI Sivat,

I doff my cap to you, for highlighting what you have.

To me its also a pointer why some systems seem to provide better sound via HDD Lossless (wav. flac. ape etc ) than Off a CD !

Arj, I found your audioassylum thread very illuminating.

FWIW, I also liked the following side link from the AA thread:


"More Than Meets The Ear"http://www.digitalprosound.com/Features/2000/Sept/RecCD3.htm

Please do post more links on the topic...

Thanks

Another nice link but this talks about the evolution of the cd transports in phillips.. found it very interesting !

http://www.marantzphilips.nl/philips_cdm_cd_mechanism_list/


AN, the link you posted is really nice...even i could understand it all in 1 reading !