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There are limits in most places, there just isn't much interest in enforcing them (in the sense that the cops don't care all that much, I imagine they would eventually respond to consistent complaints).

This. In fact, I wrote up a case study (PDF) on this issue for a technical conference. Noise just ain't as sexy as busting drug dealers.

I'm not sure that acoustics is the answer here, especially if you're talking about an 8000-ft depth. Acoustical waves travel well through rock, but exciting the rock in the first place takes a lot of force. As a comparison, ground-borne vibration propagation test equipment (used for train vibration assessments) typically put out peak forces in the 6,000 to 10,000 lbs range, and the signal is barely detectable using averaging methods at 200 ft.

You could try signal processing tricks (MLS for example, self-link to a PDF paper I wrote), but then you're trading in the peak force for massive computing power at long distances- I'm guessing several hours of number crunching for a top-of-the-line PC for several thousands of feet of depth, maybe less for multiprocessing workstations if you can vectorize the calculations.

I suspect that an EM solution would be much easier to develop.

This, IMHO, is a perfect example of the usefulness of RSS. Everyone focuses on using RSS for blogs, but RSS can be used for any data that could be useful in a syndication format. RSS Weather is an obvious example, but I've also used used RSS for sound monitoring reports.

It's not the RSS is necessarily the best format, but since it's a widely supported format, I can access the data using RSS clients on nearly any platform - including a Java client that runs on my Sony Ericsson cell phone. By baking this stuff into Office (and to a lesser extent, Windows) MS is providing a useful way for clients (of the computer type and of the writing-the-checks-type) to get this type of data into a useful format for computational, organizations, or publishing purposes.

(BTW, I'm no MS fanboy - my active machines right now include 1 NetBSD box, 2 Mac OS X boxes, 1 McLinux box, and 1 XP Tablet PC - but I think that this could be a great thing)

That may be the perception, but in many cases (but not all), it's wrong. Integrated amps allow the manufacturer to to cutomize the amp for the specific driver which can greatly improve the performance of the overall speaker. for example:

• the amp in the Sunfire sub (which is rated for 2kW, but doesn't actually deliver that kind of power to the speaker because of the back EMF properties of the speaker magnet - any other amp would be eaten alive), and
• the BeoLab 5 integrated amp (I've written about the BeoLab 5 before).
• Heck, even if you hate Bose speakers, try listening to externally-amplified Acoustimass-series speakers, and compare them to the internally-amp'd models - the self-amplified models sound much better.

I strongly agree. While I'll be the first person to defend Bose against unwarranted charges of 'crap' it's hard for me to not laugh at someone denigrating B&O, especially since their Beolab 5 loudspeaker is easily the 2nd best loudspeaker I've ever heard (behind the Wilson Watt Puppy)

IMNSHO, this comment is unfair. Your condemning the product because you don't like this 'second-rate "hi-fi" ' company, rather than the merits of the product.

True, but it's still under development. I've seen a demo of the system, and the movies accurately reflect my experience. I suspect we'll start to see technical details via professional society papers once the system is in production.

24 years? I don't know, but I did see a demo of this 10 years ago.

I won't argue that Bose's products are overpriced for the sound quality, but for some customers, they do have greater appeal than simply sound quality - for example, the WAF/SAF appeal for their acoustimass speakers is very high.

In any event, are there any videos that demonstrate the Porsche and GM systems? I like to compare the performance of the systems (well, as much as you can compare them in a video).

Why not? Active vibration control and dynamics are based on the same mathematics as acoustics, so it's all related. I went to school to learn to make speakers and wound up becoming an expert on train ground-borne vibration

Of course as a noise & vibration guy, Bose's system interests me because it could help reduce wayside ground-borne vibration from auto traffic (and even railroad traffic if the price was sufficiently low). Yeah, it's a pipe dream, and if it does happen, it would be several decades, but every little bit helps.

IMNSHO, this comment is unfair. Your condemning the product because you don't like this 'second-rate "hi-fi" ' company, rather than the merits of the product.

True, but it's still under development. I've seen a demo of the system, and the movies accurately reflect my experience. I suspect we'll start to see technical details via professional society papers once the system is in production.

24 years? I don't know, but I did see a demo of this 10 years ago.

I won't argue that Bose's products are overpriced for the sound quality, but for some customers, they do have greater appeal than simply sound quality - for example, the WAF/SAF appeal for their acoustimass speakers is very high.

In any event, are there any videos that demonstrate the Porsche and GM systems? I like to compare the performance of the systems (well, as much as you can compare them in a video).

Why not? Active vibration control and dynamics are based on the same mathematics as acoustics, so it's all related. I went to school to learn to make speakers and wound up becoming an expert on train ground-borne vibration

Of course as a noise & vibration guy, Bose's system interests me because it could help reduce wayside ground-borne vibration from auto traffic (and even railroad traffic if the price was sufficiently low). Yeah, it's a pipe dream, and if it does happen, it would be several decades, but every little bit helps.

I know Bose bashing is always fashionable, but in my experience, the Bose headsets work pretty well. They may or may not be best-in-class, but they most certainly do not "suck."

If the record company had any brains they would start pushing newer technology like SACD and DVD audio. Superior sound quality, bonus features ...

...and DRM up the wazoo.

Check out Brian Steele's DIY Subwoofer page.

Also, just to toot my own horn, check out my DIY project.