Can "Digital" damage my gear?

Hi Kijanki -- yes, it's certainly conceivable that a malicious download containing high power signals at 20kHz or so could burn out a tweeter, without being audible (to many of us, anyway!).

If you have concern about a particular download or cd, a way to check it would be with a good audio editing program, that would allow you to examine the waveform, and/or that would provide amplitude and power statistics. Sound Forge 9, http://www.sonycreativesoftware.com/products/soundforgefamily.asp, a professional program costing about $300, can certainly do that, and in fact it would allow you to easily filter out the low frequency stuff in the file and examine the waveform and statistics just for the high frequencies that might be harmful to the tweeter.

Perhaps its consumer-grade counterpart, Sound Forge Audio Studio ($55) can provide those capabilities also, and perhaps some of the better free programs, such as Audacity, can. I have no particular knowledge of those programs, though.

Regards,
-- Al

Software engineer, I work with, says that Fourier analysis of such size files will take forever. He participates in SETI program and does analysis of small files on his computer. Ideal would be small crude scanner program that looks for high amplitudes above 2kHz.

Kijanki -- Although as you realize there is a learning curve and familiarization process involved in using an audio editing program, once you attained sufficient familiarization, doing what you describe would be trivially easy with Sound Forge (and possibly with the less expensive or free audio editing programs as well).

All you would have to do is to spend a few minutes setting up a preset in its equalizer function, that would sharply roll off everything below 2kHz, and then set up a preset in its "find" function to find everything above an amplitude that you specify.

Once you had those presets in place, you would copy the file you wanted to check to a separate folder, and open the copy with Sound Forge (that avoids the risk of accidentally modifying your original). Then all it would take would be a few clicks to call up the two presets, and voila! The processing time required by a reasonably powerful, fairly recent pc running Sound Forge would be a few seconds at most.

If you want to pursue this approach, I'd suggest starting with the free audio editing program Audacity (easily findable on the web). I haven't used it, but conceivably it might be able to provide similar functionality.

Regards,
-- Al

My feeling is, and my (extensive) computer experience has been, that if you use a good anti-virus program, have a good firewall in place, keep your Windows patches up to date, and don't visit or download from questionable sites, viruses are not a significant worry.

In the last 10 years or so, during which the several computers in my house have received extensive use, most of it on the internet, I think there have only been two instances of virus infections that were not blocked at the moment of potential introduction. In both cases they were due to Windows or Internet Explorer vulnerabilities for which patches had not yet been released. They were detected within another day or two by the anti-virus program, when updated definitions were released, and no harm was done.

FWIW, I use the NOD32 anti-virus program. I use a SonicWall hardware firewall, which costs $450 but provides business-class protection for my entire LAN, with no performance impact on the computers. I also use Firefox 3 for web browsing, which is both better and safer than IE (as well as being much better than earlier versions of Firefox).

I set Windows to notify me when updates are available, rather than automatically downloading and installing them. I then use Microsoft Update to update manually. I believe that setting for automatic download and silent updating sometimes results in the process being delayed, for days or weeks. I know that was the case when XP Service Pack 3 was released.

I also regularly (perhaps once a month) use an imaging program to create an image of my entire "c" partition (in addition to doing backups of data files daily), so that if an infection were to occur I could simply reformat, restore the image, restore the data backups, and be back in business in less than an hour.

I consider all of these things to be basic to any serious use of a computer. But my observation has been that probably 95% of all computer users don't follow these or similar practices, which is why virus-writers, cybercriminals, botnets, etc., have proliferated.

Regards,
-- Al