http://world.std.com/~griesngr/intermod.ppt
The 'power point' page on inter-modulation (I think) was not looked at as I have an allergic reaction to such presentations, especially in file form, so maybe you can explain what you found as in this as technically against high bandwidth margins for complex sound recordings in a concise manner?
BTW how did you 'hack into' your profile to never show an increase in posting after first 63 posts even though you show being a member since sometime in 2006 and have posted in this thread several times with no post # change? This might be most handy for blocking tickets, maybe looking forever like a newer member with 'cleaner' record than might otherwise be credited to your screen name. Care to comment?
PPT conclusions...
Conclusions -
1. Adding ultrasonics to a recording technique does not improve time resolution of typical signals – either for imaging or precision of tempo. The presumption that it does is based on a misunderstanding of both information theory and human physiology.
2. Karou and Shogo have shown that ultrasonic harmonics of a 2kHz signal are NOT audible in the absence of external (non-human) intermodulation distortion. This BTW: means they can't be heard in the real world and that filtering them from the recording is a good thing as they can only do harm.
Again BTW I will note that I am not advocating limiting your mics to less than 20hz-20kHz. However if your mic droops 6 dB at 18 Khz I would not be concerned. My observation from years of mixing and producing music is that <40 and > 16 kHz just doesn't add anything *dramatic* to the recording. Unless of course you are using the <40 Hz to drive sub-sonic subs for the mechanical vibration effects.
My demonstration above shows that to be so. Just listen to the filtered component in isolation...
3. Their experiments put a limit on the possibility that a physiological non-linearity can make ultrasonic harmonics perceptible. They find that such a non-linearity does not exist at ultrasonic sound pressure levels below 80dB.
4. All commercial recordings tested by the author as of 6/1/03 contained either no ultrasonic information, or ultrasonic harmonics at levels more than 40dB below the fundamentals.
5. Our experiments suggest that the most important source of audible intermodulation for ultrasonics is the electronics, not in the transducers.
Some consumer grade equipment makes a tacit admission of the inaudibility of frequencies above 22kHz by simply not reproducing them. Yet the advertising for these products claims the benefits of “higher resolution.”
6. Even assuming ultrasonics are audible, loudspeaker directivity creates an unusually tiny sweet spot, both horizontally and vertically
About my profile, I didn't hack anything, you are just paranoid 
digifish
Thank you for taking time to post a very concise PPT summary.
More possible fuel for your argument against audible benefit of higher frequencies contained in an AES submitted paper summary quoted in a recent post by WifiJeff in thread:
http://taperssection.com/index.php?PHPSESSID=dc5cb19c3eae03a2a98a47d2a8b6b290&topic=80529.msg1246887;topicseen PARTIAL QUOTE:
"Incontrovertible double-blind listening tests prove that the original 16-bit/44.1-kHz CD standard yields exactly the same two-channel sound quality as the SACD and DVD-A technologies.
In the September 2007 issue of the Journal of the Audio Engineering Society (Volume 55, Number 9), two veteran audio journalists who aren’t professional engineers, E. Brad Meyer and David R. Moran, present a breakthrough paper that contradicts all previous inputs by the engineering community. They prove beyond a shadow of a doubt, with literally hundreds of double-blind listening tests at matched levels, conducted over a period of more than a year, that the two-channel analog output of a high-end SACD/DVD-A player undergoes no audible change when passed through a 16-bit/44.1-kHz A/D/A processor. That means there’s no audible difference between the original CD standard (“Red Book”) and 24-bit/192-kHz PCM or 1-bit/2.8442-MHz DSD."
...... MORE IN POST......
So you are not alone with such conclusions argued in most recent technical literature.
However, it does seem that tests with stated intention to prove something usually succeed in providing clear evidence making their point. In the past such test were designed to prove the opposite pro-wider bandwidth argument and seemed to also succeed.
Maybe both arguments hold same amount of truth depending on specific testing condition details, personal perspectives/biases, and real-world live vs. studio multi-track sound recording listening experiences.
In regards to: "About my profile, I didn't hack anything, you are just paranoid
" My profile reported by two moderators to
maybe been hacked as posts of 'way off my usual posted color' with porn images/links needed deleting on at least one occasion recently, and my signons are often detoured to show "odd images," and/or other members profiles instead of usual sign-on screen. I've been offered a new account if this continues. Found changing password not changing occasional detour events. Yes, maybe a bit
paranoid, but also having good reason to be more suspicious than my usual. Sorry to question your low post count as being odd.
