CD transports

[peanutbutterjam 0]

 

The Question:

 

How is a $2000 CD transport better than a $200 one?

 

As far as transports go the output is entirely digital, there are no analog stages that can be affected by interference/component quality/etc. So what's the difference? Digging through doesn't seem to yield any definitive answer.

 

Thanks!

[stephen chung 0]

I was thinking about this too....

[audison 0]

yes, i am also inclined to think that way. while more pricey transports feature exotic materials used in the manufacture, sometimes i think they are very overhyped. in their product literature, they may smoke out those uninformed that the quality of the pickup/servo assembly is very critical in reducing jitter or whatever crap that can present as a irrecoverable error input to the DAC....

 

a cheap PC CD writer has far more capable error correction capabilities than those used in highend home audio transports. that is what i found out when i popped in one of my very old CDs that have undergone some serious laser-rot (many miniscule gaps when looked thru strong light) into my home CD player and it skips big time. when popped into my PC CD burner, it ripped perfectly!

[peanutbutterjam 0]

a cheap PC CD writer has far more capable error correction capabilities than those used in highend home audio transports.

Ok here's the real interesting thing, many so called "high end" CD players or transports use commercially available CD player units.

 

Of course I'm not saying that the CD player drive alone is what makes up the transport, but what I don't understand is what exactly makes up a high end transport. From what I illustrated its not the CD drive itself, and since its a transport there are no analog components like DAC to speak of here. So this is just my question rephrased, what is it that make up a good transport?

 

If I were to refer you to tubeman's post regarding amps (http://www.sgheadphones.net/index.php?s=&s...ndpost&p=106852), I am looking for the 'objective' part of this issue.

Edited January 30, 2009 by peanutbutterjam

[wwh 0]

The strings of 1s and 0s are assumed to be the same (with a clean source and equal ECC capabilities) but the timing of the data when it arrives at the DAC also matters (I guess this difference is reduced when you use high quality DACs which may have a certain level of tolerance with transport and interface jitter). You may want to read the article below for more information about how the reduction of CD Transport jitter translates into 'higher quality' musical reproduction.

 

http://www.stereophile.com/features/368/index.html

 

Personally, I feel you will only be able to tell the difference if your entire audio setup is really high-end (assuming you are using an above-average quality CD transport).

Edited February 1, 2009 by wwh

[peanutbutterjam 0]

http://www.stereophile.com/features/368/index.html

Wow this looks like a really informative article, albeit very long. I'm going to read it tonight. Thanks for the link!

[audison 0]

would think jitter exists in all cdps, from cheap to expensive ones. question being how they are reduced. the report was quite dated, and advancements in digital audio tech have since evolved, so making it even less distinguishable.

[wwh 0]

Found an interesting read :

 

http://www.codebunny.org/audio/cdtransports.html

 

[wwenze 0]

A good read on transport sound:

 

http://audio.peufeu.com/node/6

 

To sum up, it's not the drive.

 

Also to add, a $2000 transport would not cost ten times as much to build as a $200 transport. But it takes a lot of precaution to ensure that the sound is perhaps half as bad hence the price. Things like vibration, PCB trace/wiring, power supply noise and decoupling/filtering capacitors, can make a difference on the digital (or analogue with regards to the clock) part of the transport.

Edited February 20, 2009 by wwenze

[Quantom 0]

The strings of 1s and 0s are assumed to be the same (with a clean source and equal ECC capabilities) but the timing of the data when it arrives at the DAC also matters (I guess this difference is reduced when you use high quality DACs which may have a certain level of tolerance with transport and interface jitter). You may want to read the article below for more information about how the reduction of CD Transport jitter translates into 'higher quality' musical reproduction.

 

http://www.stereophile.com/features/368/index.html

 

Personally, I feel you will only be able to tell the difference if your entire audio setup is really high-end (assuming you are using an above-average quality CD transport).

 

Interesting article. Kind of refreshing to note that their site still has objective articles instead of heavily hyped ones.

[peanutbutterjam 0]

Interesting article. Kind of refreshing to note that their site still has objective articles instead of heavily hyped ones.

I'm really torn now. It was so nice living in the bliss that digital source don't matter

[stephen chung 0]

I went to audit a DAC at a hifi shop 2 weeks and I think the difference lays in the DAC and not so much on the transport itself...

[ical 0]

Heard many A-B of transport, it do play as important role as DAC. Recently heard the new Accustic Arts reference series Drive II and Drive I Mk2, which performance is world apart.

 

Those who go for separate transport and DAC system will usually purchase both from the same brand to ensure the right match.

 

[wwh 0]

Very interesting reads. Actually I was wondering if anybody tried shifting the clock from the Transport to the DAC itself? Meaning making the DAC 'Master' and the transport 'Slave' to minimise signal degradation from jitter.

[cyberfrog 0]

I beg to differ.

 

I did quite extensive testing, using an old CD63SE, a new Rotel RCD-1072 HDCD and a Marantz SA11-S1 with the PS Audio DL-III ext DAC.

 

The 3 players give a fairly representation of the range of transports across a certain price range. The CD63SE uses a fairly common tpt Phillips CDM 12.1 (now called the VAM-1202/12...original $20 at Sim Lim Tower). The RCD1072 is rotel's top of the range HDCD player, using a modified Sony tpt (KSS-213). The SA11-S1 uses a proprietry SACDM-1.

 

I used the same digital coax during testing.

 

On my humble system, the difference is so obvious it makes you wanna go get the best tpt your wallet can allow.

 

I cannot explain whats the difference and how each tpt affects the sound quality. Suffice to say, the tpt makes a significant enough impact to the overall design of the CDP, regardless which end your system is.

 

 

 

Personally, I feel you will only be able to tell the difference if your entire audio setup is really high-end (assuming you are using an above-average quality CD transport).