What makes CD players sound different?

roopaudio · « **Reply #100 on:** 21 Apr 2003, 12:53 am »

At this rate, never

. Just kidding; slowly but surely it's being completed - I just need to clone myself and then lock him up in a lab. Hmm...who's got a cloning machine?

Marbles · « **Reply #101 on:** 21 Apr 2003, 01:02 am »

Quote from: roopaudio

At this rate, never . Just kidding; slowly but surely it's being completed - I just need to clone myself and then lock him up in a lab. Hmm...who's got a cloning machine?

Just run yourself through the copy machine, it's quicker that way

blizzard · « **Reply #102 on:** 21 Apr 2003, 01:26 am »

Hi Rup,

Quote

I've spent the past year writing a design thesis explaining exactly why an optimally implemented 16bit D/A is more accurate to human ears versus and optimally implemented 24bit D/A when decoding Red Book CD format. It will be published at the end of next month.

Where will your thesis be published? Are copies going to be available?

Thanks,
Steve

roopaudio · « **Reply #103 on:** 21 Apr 2003, 06:18 am »

Steve,

The paper will be submitted to various journals and organizations. Given the extremely limited scope of the topic being discussed, and the target audience, I really don't expect it to be published in full. Hopefully it will be mentioned, but that's pretty much the best case realistic scenario. Nobody wants to waste printed ink on something which has very small market relevance, and that's understandable.

That being said, I will post a .pdf version on my own private website, and make the download available for all interested parties.

Regards,

Rup

DVV · « **Reply #104 on:** 21 Apr 2003, 06:33 am »

Quote from: roopaudio

Steve,

The paper will be submitted to various journals and organizations. Given the extremely limited scope of the topic being discussed, and the target audience, I really don't expect it to be published in full. Hopefully it will be mentioned, but that's pretty much the best case realistic scenario. Nobody wants to waste printed ink on something which has very small market relevance, and that's understandable.

That being said, I will post a .pdf version on my own private website, and make the download available for all interested parties.

Regards,

Rup

Not to jump the gun, but I could publish it on my site (http://www.zero-distortion.com ) if I like it, and of course, if you give me permission to do so.

I've neglected it of late because of family problems, but it will start being refreshed on a more regular basis very soon.

If you are interested at all, that is. It has 124-128 hits per day and LOTS of downloads.

Cheers,
DVV

blizzard · « **Reply #105 on:** 21 Apr 2003, 11:16 am »

Thanks Rup,

What is your website's address?

Steve

roopaudio · « **Reply #106 on:** 21 Apr 2003, 05:08 pm »

Steve,

I can't disclose the website information right now for reasons I'll explain later, but I'll be sure to send you a private message and post to this thread when the website is ready.

Rup

blizzard · « **Reply #107 on:** 21 Apr 2003, 06:33 pm »

Thanks Rup,
That'd be great,
Steve

tmd · « **Reply #108 on:** 21 Apr 2003, 09:50 pm »

Rup,
You're a mine of information. I had an idea you were working on something interesting. I guess from reading your reply, the basic use of a PC as transport is sound. It is just the use of the Extigy card might not be such a good idea. Is that right?
I was just using the Extigy as an example of one way to do it. Michael Barnes has a piece in his monthly newsletter about a unit he has used to try out a similar approach but it acts as a dac aswell. He is developing some kind of buffer stage for these types of device to up the output voltage.
So, are my thoughts well founded with regard to the basic idea of a PC being better than a conventional transport if you take into account the ripping of music onto a hard drive first?
Thanks, Neil.

roopaudio · « **Reply #109 on:** 22 Apr 2003, 04:07 am »

Quote

So, are my thoughts well founded with regard to the basic idea of a PC being better than a conventional transport if you take into account the ripping of music onto a hard drive first?

Neil,

When comparing a traditional PC to a CD transport mechanism, one has to consider the distortion induced by a PC versus a transport. The PC has magnitudes more of EMF inside the chassis, as well as a higher latency power supply than a well-implemented CD transport solution. The problem occurs at the stage where the digital output of the PC soundcard interfaces with either a coaxial or optical interface to send to an external D/A. Optical is advantageous in that it is largely immune to all electrical field interference; however optical cables are much more sensitive to loss and jitter over distance versus coaxial cables. The ideal middle-ground solution would be a glass optical connection, but this is rare within PCI soundcards, and often the cost of such sound cards doesn't make sense when considering a dedicated transport/cd player. For this reason, a well-implemented transport will be superior to a PC output using a plastic TOSlink or coaxial digital output.

Regards,

Rup

eico1 · « **Reply #110 on:** 22 Apr 2003, 01:19 pm »

A sound card with a transformer output should provide most the benefit of optical. Any serious dac should use transformer inputs also anyway.

steve

tmd · « **Reply #111 on:** 22 Apr 2003, 06:31 pm »

Rup,
So if I were to take a unit like NorhTec sell, with a power supply that will run from 12V dc, would that still constitute a noisy platform?
From what you are saying, USB isn't an ideal way to take the info from the unit either.
I guess my thought was that the conventional CD transport has one chance to pull the data off the disk (i think) using an imperfect method to do so. The amount of data transferred is the amount transferred. Dirt, vibration, badly pressed disks and so on are all going to take from the amount of data transferred whereas the PC will reliably spit out the total amount of data every time reliably. I guess this is an idealistic view of it and the real world suggests something else entirely.