Mac or Windows
Discussing differences in sound quality between Mac and Win on an audio forum is almost impossible. Most of the time it ends up in a flare.
A reasonably sane one can be found here.
If what you want to do can be done in the MAC then you will have the easiest time doing it this way, but probably not the cheapest.
If you want the flexibility to do the most things, especially run the widest choice of software, you will be better served with a Windows machine. Unfortuanately this flexibility comes at a cost: increased opportunity for obscure problems, increased risk from malware and increased need for maintenance.
In the end you are probably better off sticking with the devil you know unless your situation has become untenable.
Software
Windows offers a far wider choice in software.
Players like J.River Media Center, Foobar, etc.
Rippers like EAC or dbPoweramp
Taggers like MP3Tag
Etc. etc.
You have more options to configure the system to your needs.
Hardware
You can choose almost any piece of hardware because that's where Windows is about, supporting each and everybody's hardware.
You can choose from a wide range of sound cards.
However when using a laptop or an outboard DAC this argument is not relevant.
The downside of this flexibility is that the system becomes more complex.
Third party software and hardware might come with third party bugs.
Apple’s absolute control in principle improves stability.
Out of the box Win7/WMP12 – OSX/iTunes
I do think the interfaces most of all have more in common that that they differ.
Both keep it simple, an interface allowing you to do the basic things.
Ripping
Both have a secure mode, both are equally badly documented about how this works.
Both don’t support AccurateRip, you need dbPoweramp on Win to do so.
On OSX XLD comes with AccurateRip support.
Tagging
Both use an online database for tagging. In case of iTunes you have to open an iTunes account and hand over your credit card number first to get cover art.
Cover art is where iTunes shines. WMP reduces it to 250x250
Audio formats
Both promote their proprietary lossless format, both don’t support FLAC natively.
Both can be configured to play FLAC using third party plug-ins.
Drivers
Both iTunes and WMP players won’t allow you to bypass the audio engine of the OS.
In case of Win you can bypass the audio engine using WASAPI in exclusive mode but you need another player like JRiver ($50) or Foobar (free) to do so.
In case of OSX there is a HOG mode, giving you exclusive access to the audio device.
Some media players can bypass the OSX mixer (integer playback) giving you a straight unaltered audio path.
Sample rate
Out of the box both will resample everything to the rate set in the control panel.
According to dCS, OSX does a better job than Vista but they don’t consider it being ‘audiophile’ grade.
However, you can set the sample rate to match the sample rate of the recording manually to avoid resampling.
Streaming AV
Microsoft is a DLNA member, Apple isn’t
DLNA is the industry standard for streaming AV.
Win has good DLNA support, OSX not.
If you want to integrate all your AV gear regardless of its brand, Win is the platform of choice.
iTunes on Win
iTunes is an interface to the audio collection.
The playback is done by QuickTime.
The QuickTime output goes to the Win audio engine.
Now you have 2 audio settings, the one in the QuickTime control panel and the one in the Win audio control panel.
If you play Redbook audio (16 bits/ 44.1 kHz) QuickTime might upsample this to 24/96.
If you have set Win to 16/44 the result will be downsampled to 16/44
Two times sample rate conversion are two to many.
Set QuickTime en Win to the same values to avoid this.
- Data Conversion Systems Ltd. (2009). Operating systems handling of sample rate.
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