downloading music versus cd `s quality

"I have been reading a lot about quality of digital music, and the question is: can I transfer all my cd~ to my Mac, then upgrade the sound quality on the Mac , via a software program"

Yes. If done right, the CD's you rip should sound just as good played through a pc as they do your CD player. As for the rest of it, I would pass on it for now. After you get your CD's ripped and sounding right, then look into high rez. Having the CD rips as a reference will be of great value when trying to set up high rez.

I've digitized my entire library, around 1100 CDs and 50ish dl's, mostly from HD Tracks. Used initially an Olive (two of them), finally waving the white flag on its finicky nature and craptastic customer service and am now happy as a loon with my Sony server. Anyhoo, I've been reading as much as I can on this topic. I'm no expert, just someone who dove into it. Some random learnings, and again I'm just a regular bloke:

1. If it's not recorded in HD, making it HD afterwards (i.e., for sale as a HD dl) I don't believe is worth it. Maybe with the exception of a remaster straight from the master tapes perhaps. However, what's leaking out now here & there is that it's rarely done. Buying a 'HD' of say, Carole King's Tapestry for example. Recorded in the 70s. Is the HD just more bits of the original recording? In which case it might sound worse not better (some argue). But, if they literally opened up the vaults, dusted off the reel, remastered in HD, then I would think (hope?) it's better.

2. When Beck won the Grammy, there was a brouhaha with HD Tracks marketing the dl as HD when in fact some of the tracks were not only not CD quality but actual MP3s. Those scamps. That news was a big eye opener for me. Stereophile wrote about this and printed the graphical analyses. HDT then added a disclaimer that 'some of the tracks are not...yadda yadda.'

3. I can say that if it truly is *recorded in HD* a la Sound Liaison, you are getting the primo supremo royale with cheese. I've got a couple dl's from them and holy guacamole that is some fine sound. Give them a try.

4. Some argue we can't distinguish HD music anyways. Pono seemed to unleash that controversy. There's a site where you can compare redbook and HD songs and take a test. I did it, it's kinda fun actually. Need good headphones for it.

5. To your question of what is the difference, I believe HD is more 1s & 0s jammed into the same space.

And lastly, a plug for the Sony server. It does some funky oversampling and digital correction and wizardry stuff automatically (which can be disabled). I think the years will show that Sony server to be a watershed product in our space, it's that good. I truly believe my CDs sound better on that Sony than via CD player. I'm all in on it.

I prolly have muddied the waters more than anything, and laid down a welcome mat for the engineering types here to flip out, but I don't mind. Food for thought anyhoo.

Rockandroller, it's going to be a very good day for you! I'm going to direct you to my latest article at Dagogo.com, on the Eastern Electric Minimax Tube DAC Supreme. While the article showcases the fabulous ability of DACs with socketed opamps to be upgraded by rolling in discrete Opamps (and there are three major players in that regard mentioned in the article), for your purposes the answer to your question lies in the article on the last page, which deals with my Mac Mini and software for upgrading CD sound.

PCM (ripped CD files)can now be sensationally upgraded to not only 192 or 384, but - get ready for it! - can be upgraded to double DSD sound (Note, I am not suggesting that they are the literal equivalent of the original DSD recordings)! Here's the best part, you can do so for under $200! I'm not yanking your chain; I have done this upgrade and now listen from my stock Mac Mini to a double DSD sound quality because I use a software by Signalyst called HQPlayer. I use an app called Splashtop to turn my iPad into a full remote desktop, which controls the HQPlayer software.

It is difficult to overstate the marvelous transformation you will experience by going this route. What will open peoples' eyes, perhaps, is the comment that this cheap change to my stock Mac Mini performed at the level of a twin tower dedicated PC setup running JPLAY on one PC and HQPlayer on the other feeding the same DAC.

You will adore the change; get ready to be freaking out with delight when you do this. Obviously, you will need a DAC capable of double DSD playback, and consider well the Eastern Electric, especially since the discrete opamp rolling pushes the results even further. :) If you wish to PM me to discuss more, feel free.

Obviously, opinions will vary on this topic file playback and upconversion, and I'm not interested in arguing about this.

As Zd stated, yes CDs can sound as good or better ripped and played through a computer based system than through a disc player. I do both.

On your Mac you would need playback software, CDs ripped as AIFF or WAV flies, and a USB DAC. I have found the learning curve for this not to be overly difficult.
There are many threads on AG that help. Also online articles.

CDs are 16bit, 44.1Khz. Often upsampled to 24/192 by a DAC or playback software.

I also like ZD’s suggestion that you start by ripping CDs prior to downloading.

Start by ripping your CDs into Itunes, purchase a budget used DAC that can be upgraded at a later date at little monetary loss, and enjoy. Once you get comfortable you can select better playback software.

Enjoy the quest!