If you were a lawyer, you would be disbarred for incompetence. Here's why:
The X-fi specs even list it as 24 bit/96k which is still 100K less then High Def Audio.
There is no textbook definition for high *resolution* audio. The defacto definition is anything better than CD quality (44.1kHz, 16-bit sampling). Getting the sampling rate up to 48kHz helps. Getting 24-bit samples helps. Having a lossless codec helps. So to say 48-24 sampling isn't high res is foolish.
Further, there is a point of diminishing returns. Increasing the sample rate to 96kHz helps increase detail but not "twice as much" as 48kHz. It takes twice as much data to reflect a subtle improvement. I consider myself an audiophile of sorts, and I can hear the difference between lossy and lossless CD; I can hear the difference between 44/48kHz and 96kHz - especially in string instruments such as guitar, and piano. There is a vibrancy and warmth, a depth, that is missing at lower sampling/bitrates. This is what the vinyl fanatics were on about all this time. But a causal listener who can't tell the difference between 128kbps AAC and a CD probably won't spot the difference.
I listen to a lot of high-res audio (SACD, DVD-A, etc.). I have an extensive collection of 96kHz and above music. Do you even know what you're talking about?
Finally, I'll point out that most high res sound cards cannot output 192kHz with 5.1 -- they are limited to 96kHz in multichannel mode and can only do 192kHz in stereo mode. And that's fine, because that's how the DVD-A spec wants it. I have only come across three 192kHz DVD-A stereo recordings and I'd be hard pressed to tell it apart from 96kHz.
The quality of the sound really isn't a whole lot different, your still listening to what? 24bit/48k audio off the BluRay or DVD disc, which is a fraction of true High Def digital audio.
I'll point out to you that all movie soundtracks are
mastered at 48-24. Until we get better theatrical surround, that's the max to expect out of any film. Blu-Ray will give you 48-24 lossless sound. And as someone who actually listens to Blu-Rays (I'll go out on a limb and say you don't watch Blu-Rays with Dolby True HD or DTS HD Master Audio sound), it's better than the 48-16 lossy sound you get out of a normal DVD.
Gotta love how you're telling people the quality of sound isn't any better and isn't truly high-res when I don't think you would even have experienced any of this first hand. Especially not on a Mac. I'll also point out that your impression that Blu-Ray is limited to 48-24 is wrong. Dolby True HD and DTS HD MA are both capable of up to 192kHz stereo and 96kHz multichannel, but again films are mastered at 48-24, so until somebody records a concert in 96-24 or puts other material out that would have gone on DVD-A or SACD in the past, the majority of sound you'll get on Blu-Ray will be 48-24 lossless.
NOW, talking about the MacBook Pro's audio output options ... your going to love this, trust me! Most MacBook Pro's actually do have a Digital Audio out, its a multi-Purpose output, the Digital output, which is BUILT IN on all the MacBook Pros, specs are as fallows: 24bit/44.1 - 192K
Yeah, I can tell you have no idea what you're talking about now... That digital audio out is SPDIF (Sony-Philips Digital InterFace). That would be an archaic means of delivering digital audio, limited to 1.4mbps. Completely incapable of delivering anything better. Incapable of delivering anything more than Dolby Digital, DTS, or stereo max 96kHz LPCM. As opposed to something modern like HDMI, which is capable of delivering 7.1 channels of LPCM, Dolby True HD, DTS HD MA, et al at up to 192kHz and 24-bit.
so lets take a quick review of this
X-FI: 24bit/92K
MacBook Pro: 24bit/192K
Yeah, Mr. Lawyer, you might want to check your specs again. The MacBook Pro (which is just using the REALTEK HD AUDIO CHIPSET, oh sorry, did I pull back the curtain?) is only capable of 192/24 in stereo mode. Which is convenient because IT DOESN'T EVEN OFFER MULTICHANNEL OUTPUT LIKE THE X-FI.
And please check the specs page -- the X-Fi does 96kHz in multichannel mode and 192kHz in stereo, just like the Realtek, er, Macbook.
In addition, I can GUARANTEE you physically CANNOT tell the difference between 48K audio and 96K audio.
I guarantee you I can. Tell me, how much 96kHz music do YOU have that you are basing this upon? I'll gladly share my list of high res music if you'd like.
and before you start, I do need to remind you that the MacBook Pro's audio out is Digital and can be transmitted via Toslink... which means... 5.1 audio is possible!!!
Yeaaaah, pity about it only being possible with 512kbps Dolby Digital or 1.4mbps DTS, which are both 48-16 and lossy... Not a problem with something that's not 20 years old, like HDMI.
Really, you're an audio engineer, and you don't know that?
You lose on appeal.