Cynic

Happy to report that MacOS 10.12.5 fixes the ticking problem on the Ayre QB-9 DSD.

I'm running 10.12.4 on a headless Mac Mini and have the same ticking problem. No matter what software source (iTunes direct, Audirvana, etc.), if the Ayre is the DAC, then the ticking happens. If I use a different DAC (Mac built-in, or my backup DAC), there is no ticking. I will update to 10.12.5 and I hope that solves it (thank you Wavelength for the info about the USB DAC problems with 10.12.4).

For a few years I've used a 2009 Mac Mini modded with an OCZ SSD, with the music data coming from an external HDD---the player is Audirvana Plus and iTunes. In my setup it sounded fantastic. However the 2009 was getting old so now I have 2012 Mac Mini with a 1TB Fusion drive (128 GB SSD plus a 1TB HDD) and 16 GB of RAM. I am a little concerned about having a spinning (i.e., noisy) drive in my player, but I feel better after reading this Ars Technica post about the Fusion Drive's behaviour. Achieving fusion It seems the Mac always maxes out the SSD before writing data to the HDD, so most of the time the computer will only be using the SSD. I am even considering moving the main music library from my external HDD onto the Mini (where most of it will go to the internal HDD, but much of it will be on the SSD). Probably I shouldn't do that but the external drive runs hot all the time and uses fans, and heats up the cupboard. In an ideal world, the computer should have an SSD only and there should be a cool and quiet external SSD or HDD storing the music. Also, as the posts above say, plenty of RAM and a discrete graphics card. High quality recordings and good cabling / components also make a huge difference of course.

Yes, this update breaks the iTunes integrated mode.

For true hifi I think you need a high quality standalone system in each room, fed by the best possible streaming device that can feed your high quality DAC, e.g., a Linn streamer thing or equivalent. The cheapest setup is Airport Express into the local room system, but judging by your system you probably want better than that. An AE can only feed 44.1 KHz material anyway and its DAC is not very good.

Have tried both Ayrewave and Pure Music for a few days now. Both improve sound. Pure Music is easier to use, in that iTunes can remain the entire user interface, with Pure Music doing all the work in the background. I have spent more time with PM because of its ease of use; the sound improvement is significant, especially on 14/44.1 khz Redbook CD material (which, before PM, I was letting iTunes upsample to 96 khz). I didn't believe that would be the case until I heard it. The Pure Music bugs from earlier versions seem to be gone. Apple iOS Remote.app works perfectly with it. PM's user interface simplicity and sound improvement make it worth the money.

Thanks for the clarification Barry and CG. I guess what I need then is auto sample rate switching, plus maximum quiet / efficiency in getting the signal out of the computer. I'm not sure what else these third-party players could be doing. Most of the quiet / efficiency work I have tried to address with hardware: separate hard drive for the iTunes library, connected by Firewire to solid-state Mac Mini that run iTunes only, etc. Since iTunes can't alter sample rate on the fly, I set Audio Midi to the max that my Ayre QB-9 can handle, which is 96khz, which means Core Audio upsamples everything else before sending to the QB-9. Gordon Rankin told me once that iTunes / Core Audio upsampling is pretty good. In short, perhaps apart from sample rate switching, I'm still not sure that I really need one of these other players for sound improvement, which means any convenience sacrifice might not be worth it. Still trying to figure this out.

To me, the main reason to use computer audio is convenience and flexibility. I want those, and the highest fidelity possible. Because I have an Apple household, I use iTunes to manage and play music. With iTunes, you get the excellent Remote App for iPad / iPod, plus all the sorting, searching, tagging, etc., plus Airport / Airplay compatibility (when high fidelity is less important). I want to control and select from a huge music library, including studio masters at high resolution, while sitting in a chair and holding an iPod Touch, but at the same time I want bit perfect sound and auto sample rate switching, etc. So to me, the benefit of software such as Ayrewave is in the back office: helping bits find their way to the DAC from the computer in perfect order and time, and with minimal computer overhead (i.e., signal noise/interference). I don't need any more user interface than I already have with iTunes. What would be ideal is a version of Ayrewave that fixes the iTunes back office so that it is bit perfect, efficient-quiet, and with sample rate switching, but leaves the iTunes front end as the only user interface, with the full support that Apple will continue to give it via Remote.app, etc., and other new investments. Pure Music suggests this is possible, so I wish Ayrewave or some other piece of software would do it, basically without anything more than some settings / preferences to manage the iTunes' back office. The ability to play Flac is nice, but not absolutely required because Max is a good converter to AIFF. Inserting another user interface on top of iTunes defeats some of the purpose of computer audio, despite the potential sound improvement.

Adobe Audition (open beta version also available for Mac OS X) is another good way to check file quality.

Sorry, souptin is right. As long as both the Mini and the iPod are on the same network, they can see each other however they have been connected to the network. Headless setup sometimes confuses.

Yes to both questions. You can control the Mini from the G4's screen just as if you were looking at the Mini's screen.

Yes, you can control the Mini using the built in screen sharing in OS X. The Mini will appear in the Finder window, in the left column under "Shared". You click on it and press the Share Screen button, and that's it. However, before all this is possible, on the Mini you must first somehow set up Screen Sharing in System Preferences / Sharing, and set up any authentication requirements you want. To do that it's easiest to connect to is using a keyboard, mouse and screen, if only temporarily. Also make sure the Mini's wifi is turned on, if that is what you will be using.

No, I have never heard any difference, and technically there isn't supposed to be any. To me, the biggest determinant of sound, after making sure you play music you actually like, is the quality of the original recording. A good 44.1 kHz recording (such as those made by Chesky Records) can sound much better than a poor 192 kHz one. Once you are beyond the really lossy formats, the format matters less. Then the problem is finding music you like that was recorded well to start with.

The cause of the poor sound you have been hearing is simple. Your entire collection (9000 tracks) on the Mac is AAC. It won't matter what output setting you use in iTunes to play the files back; the source data remains at AAC quality even if you convert it to AIFF afterwards. That is why the CD player sounds better: it is your only source right now that plays uncompressed files. You need to ditch the AAC files in your iTunes library and re-rip from scratch to lossless or raw. The better your system, the more obvious the recording's limitations are, and that is what you have been hearing.

Gordon Rankin at Wavelength tells me that Apple says it is not a bug that iTunes locks onto the sample rate when it launches. Even if it is not a bug, it is a nuisance.