I'd like to add that the Mac Mini/rega combo sounds really good....But so far I prefer the Oppo CDP/rega combo. I have little knowledge on optimizing settings on the Mac Mini/Itunes and any suggestions would be most appreciated!
I've been planning to get the Mac Mini for my Eastern Electric Minimax DAC+. Until then, I'll be running it coax with my Krell cdp. I'll be watching this thread with interest for responses to this SQ issue. From all my reading, for computer audio to achieve good to excellent results, configuring the Mac Mini, tweaks, and add-on software are prerequisites. (all of which I know nothing) I've read great feedback regarding Amarra with the Mac Mini as compared against ITunes. The software is expensive however, and I'm only willing to go so far with expense for good sound quality in a computer audio setup. In fact, I don't think great expense should be necessary for computer, DAC and everything; $1-2k should be enough. (sorry, that's a different thread!)
Buconero, I've never read anything on the web with that account. I also experimented with my big Imac and results are identical. But I stayed up late and did some research and tweaking....here are the results.
I re-ripped the files with error correction set to ON. I have a fancy looking no-name USB cable which I swapped out for the Belkin Pro Gold. I then repositioned the Merlin Speakers so I could switch sources more easily without changing my position in the room to do so. And finally....I tried some different filter settings and found that Filter 1 was best for the Mini while Filter 4 was suited to the CDP.
The result now was I preferred the MacMini sound. I don't know if this was due to the error correction or the USB cable. The difference was very small, but the Mini/rega now sounded smoother at the top end and the Opp/rega just a tad harsh. Again....very subtle and you'd have to be listening like a maniac for the differences. Bottom line: Very pleased with the Mini now. I can control it perfectly with the Ipad without a screen as well....very cool. Next I'll be adding the new Rega Apollo R to the DAC and that may turn the tables yet again.
The Mac mini will also be getting a memory bump, which according to 6Moons will do more for the Mini.
Error correction when ripping is critical.
Computer cabling is as, if not more, important than analog cabling.
The orientation of your power cable on your mini matters.
There's a OS X software optimization guide on my website - it is free.
There's more to this but this should make a substantial difference. Basically everything matters, just like analog.
Larry D. Moore
Larry, much thanks!
Next week I'll boost the memory of the Mac and try the guide's suggestions. At this point I'm glad I spent some time with the tweaks as I was initially surprised and unhappy with how the Mac Mini sounded. Now it's another ballgame! I spent an hour this morning listening and the Minimac is indeed besting the CD transport by a small margin. Most of the time you can't really tell the difference...only on top notch recordings. It's interesting that the filter settings were such a help as well.
Next up I will also be trying a better USB cable among other things.
So for Mac Mini users....don't expect perfection right off. The Mini needs some tweaking like any other audio component.
After comparing hi-res files to standard CD's I'm not a convert. As far as I've been led to understand the only limitation of the Rega USB is the fact that it's held to redbook resolution, which is not a limitation at all.
I still may try a converter, but a good one will be a costly experiment. The next purchase will be in the Rega transport coming next month.
Why don't I believe in 24 bit? I've heard 24 bit on other systems and been highly unimpressed. Unless the actual engineering has been improved, this is why....
As a friend who owns an audio salon likes to say, "There are differences you can read about and those you can hear."
Not sure that there are any hard and fast answers to this one. In my experience, different USB cables made little (if any) appreciable difference in my system. This may be DAC-dependant, and differ depending on the tech they use in the USB interface (I'm on the receiving end of the asynchronus tech developed by Wavelength as licensed to and employed in an Ayre QB-9). I've read that this tech may be more ambivalent to differing grades of USB cable. That's been my experience, but haven't explored at great length and there's no saying (at least not by me) whether this translates at all to other DACs.
Generally, though, Mini-as-transport can certainly punch with the big boys, no matter how you shake it. That said, absolutely correct that there is a whole lot that can be tweaked and improved. Out-of-the-box, plug-and-play, I don't think one should expect a Mini to blow the doors off. But with some care and tweaking, they're no joke.
Oh, and one more thing: don't rule out high-rez stuff yet. I've just begun to experiment with genuine high-rez stuff (with the correct output rate adjusted so that it's run native from the mini to the DAC), and it can be pretty darn impressive. Don't have an opinion about upsampling (other than I don't do it, I try to make sure things are run native into the DAC), but a well recorded high-rez track (the most I have currently is 24/88, but the Ayre will run up to 24/196, I think) is really much better than standard redbook. I'm far from an expert, not even a particularly well educated enthusiast yet, but I have been very, very impressed by the little I've gotten my hands on.
I use the headphone/toslink out of the mac mini and was underwhelmed at first also. Files are ripped AIFF ripped with correction on. Dac is the PS Audio DLIII. What brought this combination to life for me was the addition of a Monarchy Audio DIP. It made a very noticeable difference.
Even though I prefer my Resolution Audio cdp to the mac mini, I now listen to the mac a bit more as it's so dang convenient.
I'm glad to see Ultra_fi repost that link. I saw it before but never got around to trying it out. This weekend for sure.
Robbob - I tunes does not rip bit perfect - even with error correction on. Use program like MAX (free) with "do not allow to skip" option set ON. It refuses or takes very long time (reading same sector multiple times until right checksum is obtained) ripping some CDs that Itunes rips fast (In general, scratches along the CD up to 4mm are error corrected but between 4-8mm are interpolated). On the other hand CDP cannot go many times over the same sector, operating in real time.
I would suspect that what you call lifeless sounding can be in reality cleaner sounding. Sound with very small amount of noise or distortion always appears livelier and more dynamic (like distorted guitar to clean Jazz guitar at the same volume). I enjoy very much clean sound of my MacMini to jitter suppressing Benchmark DAC1, while others call it lifeless, sterile, analytical. There is no right or wrong here but it my case I did not enjoy it at first - have learned to listen (I guess).
I use a Resolution Audio Cantata with a Mach 2 Mac Mini, Pure Music, and a Cardas Clear USB cable and can't hear a difference between a cd and the Mac Mini. I do hear a difference when playing 96/24 files. Flac, .wav, and aiff files sound the best. I have found that the little things make a big difference in computer based audio. A powered hard drive, the USB port used, enough memory, etc.
Probably no hard fast answer to your question, but I'll offer my opinions. I suggest you read some of the "setting up a computer for audio" articles by the various manufacturers and/or audio mags. Ayre has some good info on their web site. You don't want the computer doing a lot of other stuff while it is playing music. Spring for one of the software packages that bypass i-tunes processing. I've tried Decibel, Pure Music and Amarra. They range widely in cost and feature set, but all sound a lot better than just i-tunes to me and all have "free trial". I'm not familiar with the Rega DAC, but unless it is optimized for USB use (like the Ayre QB-9), it is quite possible the other digital inputs will sound better. I'm guessing there are some reviews for your DAC out there that discuss this. With the Mac you also have an option to try Firewire - a better interface for music in most cases - if your DAC is compatible. I am currently running Pure Music and Firewire to a Metric Halo LIO-8, and it is by far the best digital ever in my house - although I never had a megabuck CD player for comparison. It certainly blows any of the mid-price stuff I've had from Cambridge or Cairn out of the water. Good luck, be patient, and experiment. Computer audio is almost as fussy as vinyl, but the results can be quite gratifying and the experiments generally cost a lot less than the vinyl equivalent.