Sure, which is why I mentioned that.
Despite my not hearing any (significant) difference between my ODAC and my mobo's sound, I would still purchase the ODAC (and even despite
not being after accurate audio reproduction), but I'll get to that in a moment. Firstly...
I didn't say I was generalising 'across the board'. I also mentioned that an off-the-shelf implementation is still not a guarantee; noise issues for example, and perhaps also crosstalk, come to think of it, so a reduction in stereo, both of which would be due to a poor 'implantation implementation' -
- of what is otherwise already implemented.
My own experience is anecdotal which is why I was careful not to make strong assertions. Nevertheless, sighted bias is generally quoted in terms of expectation bias causing people to hear differences that don't manifest when tested by DBT (double-blind testing), rather than people who are surprised to hear no difference despite expectation bias. So while my experience is anecdotal, it is worth a pinch more than the usual sighted testing that hears vast improvements that almost certainly don't exist at all. Indeed I was disappointed. Not only should I have been subject to expectation bias (and be 'confirming' the improvement over mobo sound) but I wanted to hear a difference.
In any case, if there are such things as off-the-shelf implementations then it's most certainly logical that cheap chipsets may be giving people hifi already, in well made mobos. To my mind, I would be very surprised if there were not such implementations considering the cost savings (assuming that the ODAC designer is right in saying that perfect hifi is already reacheable on the cheap). And in my care to be accurate, I also mentioned that I do not know if there is such a thing as an off-the-shelf implementation.
I think I have been careful enough to qualify my statements and not make over-generalisations. Enough to at least motivate the impartial reader to try before they buy.
For my part, I want the guarantee that the ODAC/O2 gives me of reaching audio perfection, and that any old random mobo chipset cannot give without comprehensive and independently verified specs. For this purpose I also purchased etymotics balanced armatures. So I would still buy the O2/ODAC combo. By doing this I can hear a base-line of purist hifi audio (as in high fidelity, rather than 'extremely expensive esoteric audio technology') and therefore can avoid some part of the the endless chasing after something better/purer that appears to afflict so many, and which is unnecessary if your believe, as I do, that true, objectively measured, hifi has been reached since some time ago and is not expensive. (A reason I would avoid Class-A amps in favour of cheap but well implemented and properly specced Class D amps).
For me, the biggest improvement I have experienced in my journey has been a DSP combo of 'headphone equalisation' using parametric equalizers (see the head-fi thread on that), and the rockbox 'stereo width' feature at 180%. Wow, does a lot of music come alive with that latter. (If anyone tries this, just be sure to enable stereo-width with another setting 'channel-balance -> 'custom'). I think DSP has a serious future in consumer audio. I should perhaps also mention the realisation that as a loud listener, many of the head-fi reviews by ljokerl can result in disappointment as his quiet listener reviews are not a good match. As a rule of thumb, loud listeners require flat headphones to remove honks and spikes that don't trouble quiet listeners. (Worth mentioning that deaf or 2000-4000Hz deficient listeners need mid centric, voice-forward, phones).
Unhappily, in speaker and headphone tech, while etymotics can give audio perfection/nirvana, they don't reach audio paradise in my opinion. And I don't mean the weak bass (which can be equalised in without penalty due to low distortion). My modded Fostex T50rp give a stunning 'texture' to the audio that is highly sensual and very pleasing. I've not found this present in other phones. Indeed, despite the rep of the Senheiser HD-800, I would wish to verify the presence or absence of this attribute before purchase.
Any way, nice to get all that off my chest.