Why is it so good?

Apple lossless is pretty good. Nowhere near as good as even a budget turntable, but pretty darn good. Especially considering its basically free, being that it comes bundled with every Mac. Which probably is a lot to do with it. Imagine you had to pay $5k for your Apple lossless. Which would probably be fair - if it really was as good as you say. 

Which its not. One clue, you mention adjusting tone on the computer. That speaks volumes. Get back to me when you have it hooked up to stuff good enough tone controls only make things worse not better.

Apple lossless, wave, FLAC, it's all the same. If you ripped without loss, then you have digital versions of your CDs, and the playback will be similar.

DACs on MACs have always been pretty tolerable.

Or maybe you got your preconception out of the way and just listened to the music without assuming it would be bad  (like some comments above).  Digital tone controls don't add noise or distortion, so that could be at play, or maybe you have an ambience setting on that you really like ?

"Maybe this is because the tone is adjustable on the playback on computer? Or maybe the DAC on the Mc is really good? Sounds much better than SACDs even."

ALAC is as good a format as anything. Some renderers (players) do better with uncompressed WAV, but that’s a shortcoming in those renderers, nothing intrinsic to the file types.

iTunes, if setup and working right, will send a bit-perfect signal, so at its best, it will be as good as any player. (I don’t recommend it, though. Other options are more flexible and reliable.)

McIntosh gear is pretty nice. Some may prefer other stuff, but that doesn’t make the other stuff "better" in any absolute sense. And there is a big difference between DACs in run-of-the-mill CDPs, especially those of 10 years ago or more, and today’s better ones.

As to comparing a turntable to a digital file, it depends on what you think is "better". If lack of: mechanical artifacts, wow, flutter, crosstalk, and uneven frequency response are what you mean by "better", you may prefer playing a digital file. Analog has its own magic, but it is not necessarily closer to the master tape.

I've been building AD/DA stuff as a "digital recorder" for eons.  As a tape deck hooked up to my preamp.  Currently I got a Dell laptop with an MAudio Firewire unit.   I'm looking at going to an RME unit.

I record my LPs, on a Linn LP12/ Grado Master 2 / Ekos / Lingo / Trampolin / CJ PV9 with all the fancy teflon caps.  It sounds great.  Except that since I update my cartridge every so often, then I have to re-record and I have little time to re-record 4000 LPs.

IMHO, you need 24/96 at a minimum, except that sometimes, Red Book can sound pretty good.   But, once you get up to 24/96, with a good recording you are reaching equality, sort of.  I mean they still sound different, but at that time it could become a discussion about the amps and speakers, etc... 

Lately, I subscribed to Tidal HiFi, playing it through Dell Latitude, USB, Nuforce DDA-100 and Acoustic Energy AE1s at my work desk ( working from home )...  And those masters, even at 24/96, sound fantastic.

I also have some portable DACs and various headphones, so it sounds great, and different.

I love vinyl too. So I understand how it feels when there are better sounds but you still stick to the one you love.

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