[snowshoe]

I can't comment on the USB problem you're having because I use the optical out from my macbook pro. I think it sounds just a wee bit better. As for the app nap, I'll have to do a bit more looking around. I still have the app nap option for all the other apps that had it before, so I suspect this is to do with A+. Like you, I do not have an app nap option for Audirvana Plus. It might be worthwhile uninstalling and then reinstalling A+ if you're having trouble with it. It is performing fine for me.

 

[ISeeDesignHer]

  I can't comment on the USB problem you're having because I use the optical out from my macbook pro. I think it sounds just a wee bit better. As for the app nap, I'll have to do a bit more looking around. I still have the app nap option for all the other apps that had it before, so I suspect this is to do with A+. Like you, I do not have an app nap option for Audirvana Plus. It might be worthwhile uninstalling and then reinstalling A+ if you're having trouble with it. It is performing fine for me.

Thanks. Like they say in Maine, "Is that all you done? Yeah, but I done it, three times!'
 
Multiple re-installs of OS 10.9.2 and A+, with Command-S /sbin/fsck -fy reboots/exits and Disk Utility 'Repair Disk Permissions' yada, yada, etc., i.e., "Round up the usual suspects."
 
Before re-installing A+, I even manually de-installed all remnants of A+ once using sudo rm -R on these directory locations:
  

~/Library/Application Support

~/Library/Caches/com.audirvana.Audirvana-Plus

~/Library/Preferences

/Library/LaunchDaemons/com.audirvana.Audirvana-Plus.plist

 
Get Info had the 'Prevent App Nap' box for A+ 1.5.12 on OS X 10.9.1; it disappeared on 10.9.2. Using Time Machine to revert to 10.9.1 CPRs it back to life.
 
Try this line of code if you do experience an audible drop out. Quit A+, and type (or copy and paste) in a Terminal window:
  sudo defaults write com.audirvana.Audirvana-Plus NSAppSleepDisabled -bool YES 
and then 'enter' your admin password; quit Terminal, and relaunch A+.
 
Also, if you leave A+ running overnight and then launch Console, do you have any A+ crash reports?
 
If you do not find any, perhaps the S/PDIF drivers don't need as many wakeups as the USB 3.0 drivers do?
 
What I find, running at 352.8 kHz or 384 kHz PCM, is (emphasis added for clarity):
 

Feb 27 10:44:49 Peters-MacBook-Pro kernel[0]: process Audirvana Plus[2934] caught causing excessive wakeups. Observed wakeups rate (per sec): 178; Maximum permitted wakeups rate (per sec): 150; Observation period: 300 seconds; Task lifetime number of wakeups: 45001

Feb 27 10:44:49 Peters-MacBook-Pro.local Audirvana Plus[2934]: Strong issue, need to restart playback

Feb 27 10:44:49 Peters-MacBook-Pro.local Audirvana Plus[2934]: Restarted: 0

Feb 27 10:44:50 Peters-MacBook-Pro.local spindump[2943]: Saved wakeups_resource.spin report for Audirvana Plus version 1.5.12 (1.5.12) to /Library/Logs/DiagnosticReports/Audirvana Plus_2014-02-27-104450_Peters-MacBook-Pro.wakeups_resource.spin

 
The math works out to 53,400 wakeups observed within a 300 second period!

 
I guess Mavericks is a 'guilty-until-proven-innocent' type of oligarchy. The psychometrics intrinsic to the phrase, "CAUGHT causing excessive wakeups" is, well, chilling! It suggests to me something akin to a spousal anti-snoring device commercial rehearsal that was diverted instead to Probate Court for adjudication.
 
The MCP in TRON comes to mind as well, but that's just me, I guess.

 

[snowshoe]

I laughed at that last comment! Very close to life for me - I'm the one suffering from excessive wakeups.
 
I left A+ running overnight and, no, there aren't any crash reports in console. Mavericks, as I guess you know, uses a fairly aggressive power-saving algorithm. Since USB draws power and SPDIF does not, it makes sense that you see power-saving messages and I don't. I wish I could be of more help. USB has been a major problem for Apple since Lion. I don't know why they can't get it right!
 
As for the loss of App Nap, I still suspect it has something to do with A+. Maybe it needs to be updated for 10.9.2? All of the other 3rd party apps I've checked have app nap settings. Have you check with Damien? I don't see any comments about this on the A+ forum.

 

[ISeeDesignHer]

snowshoe, thanks for checking your console logs after running A+ overnight; Sorry re 'excessive wakeups'.
 
It was very interesting to find out that you don't get the power consumption related spindumps while interfacing via SPDIF while I get a bevy of them while using USB.
 
I emailed Damien just after updating to 10.9.2 re the missing 'Prevent App Nap' option in the Get Info window, but I think he misunderstood me.
 
Perhaps if more than 'one' person (hint, hint) substantiated the missing 'Prevent App Nap' issue with him, he would jump all over it, as is his usual practice. A+ is such a great player that I hate to see this issue remain unaddressed.
 
I have 'preferred' USB over SPDIF as optical clock edge detection should introduce more jitter than using USB, but you said you find SQ is better going optical. Do you experience this at all bit resolutions and data rates available to you?
 
I must personally confess that I have become addicted to the combination of 352.8/384 kHz PCM plus sub-Nyquist lower order slope LPF filtering.
 
That is true until I switch to DSD64 and listen to Shelby Lynne's, "Just A Little Lovin'.dsf" and I am repeatedly and pleasantly awed.
 
But, then again, if choosing USB just leads to data DEREZing, then your choice must be more 'enlightened.'

 

[frankty]

Back in the Mavericks beta days I sent Damien into on App Napp. He thanked me, but informed me that it was already dealt with. Like you I noticed that there was no Info option. This is because there is no choice, as App Nap prevention is always on. So, if it's not working, then it's a bug. For my part I have noticed NO problem on my MacPro indicating that App Nap is a proplem running the very latest OS X patch level 10.9.2

I have both a Loki and Gungnir. What I'd like him to do is provide a GUI interface so I can switch all the preferences with a click as I run them each on their own USB. I'm sure the way digital is headed that I'll eventually end up with yet another DAC.

I also have the JRiver 19 Beta, but have not experimented much with it. Now that I'm running 10.9.x, it's supposed to have feature parity with Audirvana.

Cheers!
Franki

 

[frankty]

snowshoe, thanks for checking your console logs after running A+ overnight; Sorry re 'excessive wakeups'.

It was very interesting to find out that you don't get the power consumption related spindumps while interfacing via SPDIF while I get a bevy of them while using USB.

I emailed Damien just after updating to 10.9.2 re the missing 'Prevent App Nap' option in the Get Info window, but I think he misunderstood me.

Perhaps if more than 'one' person ([COLOR=0000FF]hint, hint[/COLOR]) substantiated the missing 'Prevent App Nap' issue with him, he would jump all over it, as is his usual practice. A+ is such a great player that I hate to see this issue remain unaddressed.

I have 'preferred' USB over SPDIF as optical clock edge detection should introduce more jitter than using USB, but you said you find SQ is better going optical. Do you experience this at all bit resolutions and data rates available to you?

I must personally confess that I have become addicted to the combination of 352.8/384 kHz PCM plus sub-Nyquist lower order slope LPF filtering.

That is true until I switch to DSD64 and listen to Shelby Lynne's, "Just A Little Lovin'.dsf" and I am repeatedly and pleasantly awed.

But, then again, if choosing USB just leads to data DEREZing, then your choice must be more 'enlightened.'

The only reason that I use USB with A+ is that the MAC OS will max @ 96kHz. Have you found different? Also, with my Mac Pro clone I can't seem to get the DAC to even see either toslink or SPDIF - even though wired direct to the motherboard. It's damned annoying that the toslink spec maxes out @96kHz because some idiot choose to use cheap plastic and visible light instead of REAL fiber.

 

[ISeeDesignHer]

I have a Hegel HD-11 NOS DAC that I was driving optically with an rMBP, using Channel-D's Pure Music. It wouldn't run faster than 96 kHz, and, since SPDIF is unidirectional, I found that I had to get Midi-recognized using USB and then pull the USB cable - it then found the optical port. I'm not sure, but I think the audio and the optical are driven from the same headphone driver IC. 
 
Despite the existence of widely published specs stating that Apple's coaxial Headphone/SPDIF port can do 192 kHz, it is a lie. See http://www.channld.com/computeraudio.html and scroll down to the optical section. I pushed very hard on Channel-D before becoming educated on who is to blame for the 96 kHz limitation.
 
BTW, it is not a cheap plastic limitation of the fiber; it is the fact that coreaudio can't send PCM to the headphone/optical driver chip faster than 96 kHz, IMHO.
 
That is why I switched to USB and started using DAC drivers that shipped with H/S DACs.
 
With a Chordette QuteHD high-OSR DAC using A+ 1.5.10 on a mid 2012 11" MBA under 10.8.5, I play 176.4/192 kHz PCM and DoP DSD64 all day long, and LOVE it. It is BEAUTIFUL!
 
Sadly, when I use my late 2012 13" rMBP using A+ 1.5.12 driving an even more over sampled DAC (Chordette QuteEX) on OS X 10.9.2, I run into multiple issues. I can run 352.8/384 kHz PCM and DoP DSD64 and DSD128 over USB and hear great sound out of the QuteEX, for a while.
 
Then, I get stutters and crash-dropout-restart events.
 
I've tuned everything under my control, and then it is ALMOST good enough to use for a Show Demo; but it is 'almost' good enough like the odds of living through Russian Roulette is 'almost' good enough.
 
There are 3 'usual' suspects to round up; 1) A+, 2) OS X and 3) Chord USB drivers (from M2Tech, I believe).
 
The good news is that the bug(s) do NOT 'originate' with A+.
 
The bad news is that A+'s developer is one of the few people who understands the USB driver buffer wrap time stamp bug and the aggressive App Nap problem. 
 
Why is that bad news?
 
Well, notice that the companies involved (other than Avangate) do not have his considerable talent and knowledge directly available to them.
 
Apple, Chord, Avangate (substitute Channel-D, JRiver, BIT PERFECT, etc.).
 
It would accrue to everybody's benefit to cooperate in such a way as to restore the ability of Apple laptops to play audiophile quality digital files through 3rd party players out to external ultra-performance DACs.

 

[rbnjr]

wow, nice list of alternatives to itunes as i have ever seen. has anyone reviewed them to rate which was the sonically better one?
 
thanks again.

 

[rbnjr]

does the software for Audirvana auto update as needed on a mac computer or do you need to visit the website once in a while to check for the updates?

 

[NinjaHamster]

It

does the software for Audirvana auto update as needed on a mac computer or do you need to visit the website once in a while to check for the updates?

It has an option for auto updates.

 

[frankty]

The 96kHz/cheap plastic fiber is a chicken/egg problem. Because of the fiber spec, the OS limits the rate to 96k, even if you used glass that would go far faster. Totally artificial limitation. "Nobody will need more than 640KB of memory."

 

[ISeeDesignHer]

  does the software for Audirvana auto update as needed on a mac computer or do you need to visit the website once in a while to check for the updates?

Like finding a trans-Australian rest stop driving cross country, you're in luck! (he he)
 
Audirvana Plus auto notifies you when an update is available at launch, and, if so, then kindly asks you if you wish to install it. Furthermore, it is very good at finding your license file, so, even if you retro-reinstall from any prior .dmg disk image, you will be 'licensed'. No 'fly once, pay twice' going on here!
 
I hope this addresses your question, rbnjr.

 

[ISeeDesignHer]

  wow, nice list of alternatives to itunes as i have ever seen. has anyone reviewed them to rate which was the sonically better one?
 
thanks again.

I'm a newby in this forum so I don't know if anyone has published a shoot out on DACs here.
 
In general, there are two practical ways of learning about DAC competitive performance prior to $he££ing out € ¥; a) Find, and read, full blown test reports done (preferably) with the usual A/P SYS-2722 analyzer, or b) read here where people have voted with their pocketbooks/wallets.
 
DACs are incredibly satisfying, idiosyncratic but seductive life altering additions; absolutely terrific, until you see the 'next' one walk by and start quoting Robert Frost's, "The Road Not Taken." (Remind you of anything else in life?)  IMO, the 'best' DAC playing mp4s from iTunes will sound _worse than a mediocre DAC driven by the ^best player fed by super high resolution digital audio files.
 
Measurable DAC parameters like SNR, THD & IMD evolve quite slowly, actually.
 
You've got to treat it like buying an HDTV - it is a multi-year investment. Fortunately, the quality of available media will be your true limiting factor for years to come, if you buy one of the top ten DACs and use a player like Audirvana Plus.
 
Anyway, I believe I've already spilled the beans on my preferred DAC, in earlier posts.

 

[ISeeDesignHer]

The 96kHz/cheap plastic fiber is a chicken/egg problem. Because of the fiber spec, the OS limits the rate to 96k, even if you used glass that would go far faster. Totally artificial limitation. "Nobody will need more than 640KB of memory."

Well, you have very effectively revealed the true absurdity of this 'artificial' optical speed limit by sending it out over kilo-miles of 'optical fiber' carrying 6 or 8 orders of magnitude more bandwidth than needed for 24b/96 kHz digital audio.
 
Still, I believe that most MACs split the audio stream so that the DAC/headphone Amp/Equalizer codec chip gets fed data at the rate limit of the DAC only, and the IR SPDIF TXR is typically downstream of this bottleneck whereas, with 3rd party drivers, USB will do 4X as fast or more.
 
The real thriller is Thunderbolt's 10 Gb/s ability to output HDX-SDI with HD/SD embedded video plus Dolby 5.1/7.1 surround sound audio - and you can then buy a Thunderbolt HDX-SDI converter for your MAC that outputs all of that on its own SPDIF optical port.
 
Go figure.

 

[Currawong]

  DACs are incredibly satisfying, idiosyncratic but seductive life altering additions; absolutely terrific, until you see the 'next' one walk by and start quoting Robert Frost's, "The Road Not Taken." (Remind you of anything else in life?)  IMO, the 'best' DAC playing mp4s from iTunes will sound _worse than a mediocre DAC driven by the ^best player fed by super high resolution digital audio files.

 
The Road Not Taken indeed. I disagree with you on your second point, but not specifically with iTunes files, but when it comes to less than "super high resolution digital audio files." Lately my favourite listening has been done with music such NPR Tiny Desk concerts on Youtube. A well-made recording beats all in my experience, even if it is played back from an AAC file.
 
Lately, for something different, I have been using Vox for playback. It seems to have come quite a long way for a simple player.