Amarra 2.4.2

Intrigued as to why you a trying it? iTunes on your Mac should be all you ever need?

 

There are lots of comments on other forums on the same issues (Computer Audiophile for instance).  The vertical window issue is apparently a known bug.

 

I am sticking to Pure Music for the time being, no issues for me.

 

Some claim that the sound is better by using an other player, others can't hear the difference. 

One of the key advantages of Amarra (same goes with Pure Music and others) is that it switches the sample rate automatically so that you don't have to go Audio Midi every time you want to listen to HiRes files.  Also supports FLAC, which iTunes does not

Yeah I joined Computer Audiophile shortly after posting here, because it seems to be one of the few forums that Sonic Studio actually visit. Seems my issue with 192k files is because my DAC won't support higher than 96k and Amarra won't downsample on the fly, unlike Pure Music, BitPerfect and probably every other player out there. It has background tools to resample to-and-from any bitrate you desire, except they don't work (ie they crash). It has loads of other bugs too. In fact it's quite possibly the most bug-ridden piece of commercial software I have ever used.

That suggest that iTunes is resampling prior to outputting to the souncard?

I though the whole point of iTunes in OS was that (unlike windows default operation) it doesn't resample, in which case it should simply present the data at native rate?

Surely there is a way of setting up iTunes to do this?

JRMC resamples to 64 bit / can't recall to conduct and signal processing (DSP etc) and then converts back to the native rates for streaming into the output device.

i'd like to try a media player that does no resampling whatsoever (so no DSP, room correction, volume levelling etc etc) just to see how it compares - I suspect I will hear no difference.

You'd think so wouldn't you, but I can confirm (having just this second tried) that iTunes on its own does not switch the bitrate properly.  I just played some 24bit 96kHz hi-res audio using nothing but iTunes and my DAC still says "44.1".  Running via Amarra (or even just the 'lowly' BitPerfect) switches the bitrate on the DAC automatically to 96k, which is correct. Suspect iTunes on its own doesn't switch the bitdepth either, which is set in Audio MIDI Setup to 16bit by default.

In which case my recent hatred for Windows and a desire to migrate to Mac in the future is rescinded. Sorry Bill to have dissed you so much in the last few days. From what I've read, it's a damn sight easier to configure windows to play native file types so long as you use an "audiophile" media player, of which there are a few about.

Aye. The whol bit perfect, er, bit, was my soul reason for considering an Apple a couple of years ago, but you live and learn.

Indeed.  Quite why iTunes doesn't switch the bitrate properly is anyone's guess, but the proof is right here that it doesn't.  So if it doesn't, then that must mean there is some kind of processing going on, hence why the add-on players like Bit Perfect, Pure Music, Amarra and others sound different to iTunes.

Based on my demos, Amarra is my favourite in terms of sound, but it's a bug-ridden mess that customers have effectively been paying to beta-test for over three years now. There's no sign of them getting it right either, as each release seems to bring with it a different batch of 'idiosyncrasies' (as its disciples like to call them).

I'll stick to BitPerfect I think.  It just does what it says on the tin and it cost less than a tenner.  And yes it too switches the bitrates and bitdepths properly.

Just tried a test from the other perspective. I set the default bitrate of my HRT streamer to 24bit 96k in Utilities > Audio MIDI Setup, which made the steamer's '96k' LED light up.  Then I opened iTunes on its own and played a 44.1 CD rip to see if iTunes would swap it back to '44.1'.  It didn't.

iTunes and core audio only change the audio data if the sample rate of the audio file doesn't match the Audio Midi setting.  So, if you set Audio Midi to 16/44.1  and play a 16/44.1 in iTunes there will be NO resampling/changing the data.  If you want to play, for example, a 24/96 file then you MUST change the Audio Midi setting to 24/96 and you MUST restart iTunes after making the change, otherwise resampling will happen.  Everytime a sample rate change is made in Audio Midi, iTunes must be restarted and the Audio Midi settings must match the sample rate of the audio file if you want bit-perfect playback.  It's a pain if you have a lot of music at different sample rates but it is incorrect to say that iTunes isn't bit-perfect - it is if you have the correct settings in Audio Midi.  The reason iTunes needs restarting after making a change in Audio Midi is because it takes a snapshot of the output device settings at startup. 

If you don't follow the correct procedure you can end up with your audio being resampled twice, eg: you decide you want to play a 24/96 track so change the Audio Midi setting to 24/96, but you forget to restart iTunes so iTunes thinks the output device is still set at 16/44.1 and downsamples the file to match it, then Core Audio (via the Audio Midi settings) will resample the file back up to 24/96.

Apparently there are Apple scripts that will do all the opening and closing and restarting for you with a mouse click but I've never properly investigated this.  The Bit Perfect player seems like good value to not have to concern yourself with any of that if outputting directly to a DAC, it would be no use to me as I use Airplay.

The answer to this is something to do with the way Core Audio handles system sounds, iirc.  It's a long time since I read an explanation of this and, of course, I have no way of knowing if the explanation was correct.  And also because it is only a tiny, tiny, miniscule percentage of iTunes users who are aware that audio files at higher bit-depths/sample rates even exist, and that is before getting into the argument of are they even necessary given the limitations of human hearing and the kit playing the music, it is probably not worth Apple doing it.

I am switching the sample rate and bit depth on the fly, the sample rate is switching on the DAC accordingly. iTunes doesn't do this itself however, all done manually.

Indeed but for a company which says music is in its genes I'm surprised there isn't an option within iTunes to perform essentially what BitPerfect does, ie bypass Core Audio, take full control of the soundcard/DAC and switch the bitrates and bitdepths as appropriate without needing to restart iTunes.  There isn't even an option anymore to buffer the playback to RAM, which is something else that has been reported to improve the sound.  It just needs one checkbox in the iTunes > Preferences > Playback, maybe label it just 'Hog Mode' with a release-note explaining what it does and why you might want it.  As you say, they just simply mustn't think it's important enough. Inbetween time the makers of the add-on plug-ins are rubbing their hands together filling the gap.

iTunes (and any other media player) will read the file into RAM anyway, whether you want it to or not.  Not that it would matter anyway, almost every modern dac will have adequate jitter rejection built into the chipset (I'm assuming that jitter is given as the reason for buffering being desirable).