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User: renehollan

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  1. Re:Cables are an engineering compromize on James Randi Posts $1M Award On Speaker Cables · · Score: 1
    Yeah, I took the resistance per foot of 22 AWG cable instead of 12 AWG, so I was off by a factor of about ten. But I forgot to double the cable length (out and back) so make it 5. About a damping factor of 50. The point is that you don't want to use 22 ga wire. It can't carry the necessary peak current anyway.

    Inductance of straight cable is negligible, but any curve, or worse, coiling, will increase it dramatically. Is this audible? Probably not.

    I've taken the approach of using a decent amp with plenty of headroom (to minimize transient distortion which can kill ribbons), coupled with decent speakers, and hefty short speaker cables, with balanced runs to amps co-located with the speakers.

  2. Cables are an engineering compromize on James Randi Posts $1M Award On Speaker Cables · · Score: 1
    I have a pair of Bohlender-Graebner Radia 520i speakers and used to own a pair of Carver Silver ALS. I happen to like the ribbon sound.

    These are ribbon drivers, crossed to two woofers, and are intended to be combined with a subwoofer for content under 80 Hz (mostly important for organ music and movie effects).

    The thing with ribbon speakers is that they take the concept of the voice coil in a magnet and stretch that coil out into a single line, bonded to a thin film, like kapton, and hold it in a strong magnetic field. Every good slashdotter knows that current in a mag field results in force, and that moves the film (cone in a traditional speaker). Ribbon speakers have the advantage that they radiate cylinderacly instead of spherically, avoiding floor and ceiling bounce. They are hard to cross to cone speakers though, and do not far well much below 250 Hz. Absolutely amazing in the midrange (where the ear is most sensitive) and highs, though.

    Anyway, back to engineering.

    The force you get is proportional to the current in the wire and the strenghth of the magnetic field. IIRC, the old Carver Silver ALS used alnico magnets and had an attractive force of about a 1/4 ton between the front and read magnets. O.K. Add current. Lots of it. Ribbon speakers do not "blow" if you overdrive them: they catch fire from the hot wire igniting the film. The point is that they tend to be inefficient (88 dB/W/m is pretty good for them) and need lots of power, espescially at the peaks. They have low impedance as well.

    So, you need an amp with low output impedance (though it's not so crucual that it have it at low frequencies unless your not biamping and are using it to drive the woofers and a passive sub as well (which was the Carver Silver ALS setup: 3 12" open frame subs per speaker).

    The last thing you need is a wimpy speaker cable. Sure, one would think that a low enough gauge of wire would do, and indeed, Carver recommended 12 ga. lamp cord and to avoid expensive cables. Though, bigger is better here, when it comes to a long run of, say 20-25 feet. You really are best off keeping the amps close to the speakers, though then you have long interconnect runs where the cable capacitance starts to matter because of the high-impedance amp input. Digital amps, like the Tact Audio series avoid the long analog run, but are expensive. For most people, a long speaker run is better than a long analog preamp run. Of course, you can compensate for the high-end rolloff in a long preamp run in a good preamp, but unless you have the hearing of a young child (better than 20kHz), you likely won't notice.

    So, back to the fat speaker cable capable of carrying a lot of current (and you do need a lot for a musical peak from a ribbon driver: hundreds of watts despite an average power level of around 100 mW: if the minimum listening level is 30 dB at 4 m from a ribbon driver, and the peak is 110 dB, that's a range of 80 dB or a power ratio of 100 MILLION. 30 dB at 4 m from a ribbon is 36 dB at 1 m, or 6 microwatts. 110 dB is 116 dB at 1 m or 645W -- about 50 volts at 13 amps driving a 4 ohm ribbon). A fat enough cable has lots of inductance. Guess what that does to your sharp drum strike (which has a quick attack followed by lots of low-frequency decay). It is no longer as sharp.

    Now, 12 feet of 12 ga. cable has a resistance of about 0.23 ohm. Assuming the output impedance of an amp is 0.02 ohms (like a decent Odyssey Audio Stratos Plus at US$1300 or so), we have 4.25 ohms in the total circuit for a damping factor of 4/.25 or 16. That's pretty shitty, actually. 20 is the minumum acceptable, and 100 is grand. So, you shorten the cable, placing the amp close to the speakers, or get fatter cables (say 10 guage or even 8 guage), but then the inductance goes up. Yes, all this varies with frequency, but you get the idea (and inductance matters more at higher frequencies)

    On top of all that, you have to deal with the mechanical connection of the speaker cable to the amp and speaker. That can b

  3. Re:GPL no more. on Resolution of BSD-GPL Wireless Code Dispute? · · Score: 1
    We charged millions of dollars for the binaries, as part of a larger, supported, system. and included the source free of charge. There was no extra charge for the source, nor were there restrictions on redistribution.

    In fact, we had one customer who BALKED at receiving the source! We had to explain that we were legally obligated to do so.

  4. Re:GPL no more. on Resolution of BSD-GPL Wireless Code Dispute? · · Score: 1
    Private forks aren't a real concern for large, active, projects. But, in my case, I made changes to SYSLINUX and Anaconda, that allowed support for headless installs that were configured on a per-machine basis by config scripts on floppy in addition to the original install media. One mod permitted the wiping out of the existing hard drive if an appropriate serial port dongle was installed as well (install CDs that wipe stuff out on their own without asking are baaaaad.)

    It wasn't a BIG deal, but it bugged me that it could not be shared with the community.

    On TivoIzation, I see the position of the FSF as clear. GPLv2 was always vulnerable to this sort of thing, as well as dynamic linking (when it was novel), process wrapper shims, etc.

  5. Re:GPL no more. on Resolution of BSD-GPL Wireless Code Dispute? · · Score: 1
    You quoted from http://www.fsf.org/licensing/licenses/info/GPLv2.html selectively :

    "3. You may copy and distribute the Program (or a work based on it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one [emphasis mine] of the following:

    a) Accompany it with the complete corresponding machine-readable source code, which must be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or,

    b) Accompany it with a written offer, valid for at least three years, to give any third party, for a charge no more than your cost of physically performing source distribution, a complete machine-readable copy of the corresponding source code, to be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or,

    c) Accompany it with the information you received as to the offer to distribute corresponding source code. (This alternative is allowed only for noncommercial distribution and only if you received the program in object code or executable form with such an offer, in accord with Subsection b above.)"

    We distributed under 3a.

    Those to whom we distributed could have freely redistributed the code, but as the aggregate was useful to their potential competitors, and they paid us a lot of money, there were disinclined to do so.

    Believe me, we dotted the I's and crossed the T's on this one: we had RMS give a lecture to our devs.

  6. Re:GPL no more. on Resolution of BSD-GPL Wireless Code Dispute? · · Score: 1
    Just how does it violate the license? To each recipient of binaries, we provided the sources, licensed under the GPL (yes, including our changes). They could have redistributed if they wished. They did not.

    If there is a bona-fide GPL violation here, I'd be happy to testify as to what we did, but I don't see one.

  7. Re:Yeah but... on Titan's Tropical Weather · · Score: 2, Informative
    No.

    Methane, while produced in the gut of most animals, is odorless. The smell of flatus, to which you seam to be alluding, is mostly due to sulfur-containing compounds: Hydrogen Sulfide (in the case of the notorious "egg farts"), and various mercaptans, IIRC.

  8. Re:GPL no more. on Resolution of BSD-GPL Wireless Code Dispute? · · Score: 2, Insightful
    Nobody can make your ISC/BSD/MIT/whatever-non-GPL licensed code non-free. They can make their modifications to your work non-free, but so what?

    Yes, but they can't redistribute the combined work of "your" code and "their" modifications, in binary form, without redistributing the source to their modifications. That's very significant if their goal is to profit from the combination via redistribution.

    The argument goes like this: "Why should you freely benefit from my hard work when I can't benefit from yours?" the BSD camp doesn't care (as far as commercial lockup is concerned) where the GPL camp does.

    The argument that the GPL is "restrictive" or "non-free" in the sense that it does not permit the "freedom" to make derived works "non-free" is simply semantic bull feces. Without a license, copyright (at least in the U.S. and similar places) would grant NONE of the freedoms the GPL does. The fact that it does not grant ALL freedoms instead does not make it "restrictive". The fact that it grants many makes it "free" (though "liberal" might be a better adjective).

    GPLv2 had a number of weaknesses and I think GPLv3 retains some of them. For example, I once was employed by a company that took much GPL code, made significant enhancements (particularly to the Anaconda installer, and SYSLINUX), redistributed the result, but did not share the enhancements with the "community"... all in accordance with the GPL.

    How?

    Simple. We DID distribute source to all our recipients of the combined work, some half-dozen of them, for millions of dollars each. Each of them had absolutely no interest in further redistribution, having paid the high price, and so the enhancements effectively stayed "locked up". Pity that: I thought some of them were useful.

    As far as a GPL-hijacking of BSD code is concerned, it seams to me that the combined derived work can be licensed under the GPL, so long as the original BSD bits (including bits that were deleted) can be extracted and taken private. What part of "Portions licensed under the BSD license" is so hard to understand? Of course, I'm muddying the difference between derived work and aggregated works here, but if I combine A and B to produce C, and can yet recover A and B from C, who's to say it isn't an aggregate? I fact, if I simply aggregate A and B, and provide the recipient the mechanism to produce C from them for his own use, the aggregation argument is even stronger (another potential weaknes of GPLv2).

    A court might not see that "hack" in a positive light, and argue that the combined work is a derivative of BSD-licensed code and therefore has to be redistributed as such, but even that can be overcome: imagine I have a box into which I download A, and B. I can ask the box to produce A or B. The box, however, can use A and B in an interesting way. Who's to say the box does not aggregate A and B? Who's to say that C is not a compressed version of the aggregate of A and B? I think that if something has all the properties of an aggregate, a strong argument can be made for treating it as an aggregate.

    Of course, that wouldn't be playing nice with the BSD folks, but it strikes me as possible.

  9. Re:Worthwhile Canadian Lawsuit on Massive Canadian Class-Action Cellphone Suit Is Approved · · Score: 1
    LOL.

    Yeah, I can take a joke (picture an over-taxed Canuck getting his green card and exclaiming "I'm free, I'm free!").

    Anyway, the Inuit crack is actually ironic: the vast, barren, Canadian north drove the manufacture and launching of the first TV satellites so the Inuit could get TV.

  10. Re:The True Legacy of the DMCA on US Register of Copyrights Says DMCA Is 'Working Fine' · · Score: 1
    The DMCA clauses which make reverse engineering illegal under any circumstance which is not specifically granted an exemption for fair use need to be repealed. The burden should be upon the copyright holder to prove that the specific instance of reverse engineering is being used to infringe their copyright, not upon the reverse engineer to prove that whatever they are doing is not infringement.

    There are two problems here: First, a judge comparing a claim of "infringement" against a defense of "fair use". All fair uses infringe on what the copyright holder might wish. So, let's re-word that considering that the lack of a fair use is what constitures legal infringement. A fair use, therefore, is a valid defense against a claim otherwise (i.e. infringement).

    The second problem is whether a use is fair. The law, as written, makes all uses that are not explicitly established as fair, as infringing. This is wrong. The law can establish uses that are definitely fair, for example, though legal precedent where such uses are found to be fair by the courts, or are defined to be fair, by statute, and this makes a defense of such a use as fair easier. However, this does not mean that other uses are not fair.

    A fair use is one that does not substantially diminish the copyright holder's ability to exploit their work for profit. Parody, criticism, archival of entire works, or small exceprts of larger works, have all been found to be fair uses. The legal bar may be higher to establish that a new use is fair than to simply establish that the use in question is one that is already recognized as fair (the classic example is the Betamax decision, which found that so long as a use does not break existing law, it does not matter if it facilitates illegal activity: copying copywritten videotapes is not criminal -- distributing the copies is). This is sensible, of course, since many things can be used to commit a crime: just about anything that can be thrown can be thrown at someone.

    As far as anticirvumvention is concerned, what should matter is intent: is the intent to infringe (where a fair use can not be established), and has reasonable care been taken to not facilitate infringement? In many places, leaving one's car unlocked and unattended is illegal: it facilitates car theft, joyriding, and other nusances. The case for requiring firearms to be kept secure is even stronger.

    All that should be necessary of a user of copywritten material, or a provider of circumvention tools, that they exercise a reasonable effort to protect the copyright holder's interests.

  11. Re:For all you old farts out there on GPS Transitions to New Control System · · Score: 1
    and EBCDIC.

    Having cut my teeth in a CDC shop running NOS, that's EBCiheaDIC to me. 'course DISPLAY CODE wasn't much better, save for the occasional sending of :D to a terminal.

  12. Re:*cough* below the speed limit? on Canadian Bureaucrats Don't "Think Different" · · Score: 1
    Yeah, Seattle drivers blew me away. Sure, there's always some idiot somewhere, but, for the most part, it was bliss driving there.

    As for ice, that's the one thing they're not used to, though it's understandable.

    I grew up in Montreal, and having driven there, Toronto, and Chicago, in winter, you know how to deal with ice, and treacherous black ice.

    We had a bit of a winter storm in Seattle last year, and traffic was hopelessly clogged, with 405 closed northbound on all lanes for hours. I was prevented taking Paradise Lake Rd. to get to 522 and Monroe by a cop who didn't believe I could make the one small hill there, and ended up taking 11 hours to get to Monroe from Redmond. I was *amazed* at the cars in ditches -- it wasn't *that* bad. I had chains if necessary, but I still wasn't allowed to proceed. Grr.

    Living in Dallas when we had a bit of snow was fun: no one was on the roads when I went to work, and I was stopped by a cop who was wondering why I was traversing the dangerous roads. Once he heard my Canuck accent, he said, "You're not from around here, are ya?". "No, originally Canada," I replied. "Ah, sorry to have held you up, watch out for the locals."

  13. Re:*cough* below the speed limit? on Canadian Bureaucrats Don't "Think Different" · · Score: 1
    I've lived, and driven, in Chicago, Dallas, Toronto, Montreal (very little), Seattle, and most recently San Diego.

    Chicago: run of the mill rudeness. Hard to merge. Gotta force your way in. Do not signal a lane change -- other guy will just speed up (though the general strategy is signal, slow down, merge behind, and ride his ass for a while). Typical.

    Dallas: can't trust a driver's signal. Ever! Easier than Chicago, though. Oh, and if you think you can turn left once in the intersection waiting to turn and the light changes, think again: it might still be green for oncoming traffic. At least one intersection in Allen, TX works that way.

    Toronto: Merge? You think you gonna merge? Who the fsck do you think you are to get to go where I wanna be?! I guess they're wanna-be New Yorkers. Torontonians in general were the rudest people I ever met anywhere (as in the neighbours got indignant when I hired a kid to mow my lawn: "who the hell are you to not be taxed enough that you can hire help?").

    Montreal: Like Toronto, but mostly in French. Oh, and a "pont" is a bridge.

    Seattle: People let you merge. They slow down if necessary. Yield right of way when they don't have to sometimes and that can get confusing (as in you want to yell at them "go, doofus!" but don't 'cause they think they're being nice.) Some places are wiered, though: like freeways where some entrance ramps are HOV-only. Montrealers do have an inate sense of right of way and lord help one who is mistaken.

    San Diego: Drive fast. Very fast. No one signals (which frustrates the hell out of me when I want to make a left turn and don't know where the opposing traffic is going to sneak in a turn). Merging at high speed just *works*, though. Lots of medians and legal U-Turns in intersections.

    Each city seams to have its unique driving culture, and things work best when one fits into it: driving asertively when necessary and politely when customary.

  14. I want an 802.11n solution for Linux on Does 802.11n Spell the 'End of Ethernet'? · · Score: 1
    802.11n USB dongles and ndiswrapper just aren't working for me -- constant lockups.

    I want to serve 1080i and possibly 1080p video to a MythTV client box hooked up to my HDTV and would like to avoid an ethernet cable (which is what I'm using now).

    The client actually has a 500 GB disk drive (in a Silverstone LC08 case), with all my static content (ripped DVDs and CDs, and I own all the original media), so I can just pick it up and take it from one place to another (I keep homes in California and Washington), but recordings stay on the server.

  15. Re:Don't play games with your parole officer on Pirate Banned From Using Linux · · Score: 1

    How is that a parole violation? He IS using Windows, and further more, the tracking software has the opportunity to check everything on the Windows box, like the traffic that enters and leaves it. Saying you MUST use Windows is NOT the same as you MUST NOT use anything else AS LONG AS the tracking software can observe what you do.

  16. So? Can't he use a Windows box to route? on Pirate Banned From Using Linux · · Score: 3, Insightful

    And have Linux boxes behind it?

  17. Re:Naga..naga..nagannahappen on ISP Guarantees Net Neutrality, For a Fee · · Score: 1

    No, I don't host a site there. I COULD if I wanted to, without violating my TOS. www.hollan.org is down until further notice.

  18. Re:Naga..naga..nagannahappen on ISP Guarantees Net Neutrality, For a Fee · · Score: 1
    Er, Company C likely has a contract with company V to not DO that.

    Look, I get my internet connectivity from Comcast, yeah, a cable company, for the first time (always had DSL before but am too far from the CO now, and trying Clearwire sucked million year old eggs).

    Guess what?

    I run my own mail server on port 25 (no, I WILL NOT relay your traffic), can open any inbound port I want (even port 80), and share whatever content I have the right to share. I have the holy grail of cable internet access: a static IP address with the right to reverse resolve it to whatever domain I want.

    I have Comcast's lowest tier of business service: their teleworker package in San Diego: 10 Mb/s down (and I get close to 7 from most test servers), 1.5 Mb/s up, static IP, no ports blocked, no inbound or outbound shaping.

    Of course, I pay $105 a month for this. Consindering I paid $60 for 1.5M/384k DSL in Seattle with a static IP and no filtering, that's not too shabby. I'd rather pay a bit less as I don't need the bandwidth I have, but that's the market here.

    Now, I use it for personal reasons, and am not trying to conduct business on the 'net. If I were, I'd be pretty upset that Comcast might shape traffic to their consumer class customers some of who I might want to do business with on line. But, it's their pipe, so I guess they get to charge for preferrential routing.

    But, wait! That can't go on for ever. See, they have a monopoly in the areas they serve. The can't legally leverate that monopoly to bolster a business in another area, oh, like restricting those who do not pay extra for their business traffic to have preferential routing from doing business. In fact, if Comcast has a stock interest in some of the businesses that do pay for preferrential routing, it's an even clearer case of monopoly abuse.

    Of course, like all things litigous, this will take time to settle in the courts.

  19. Re:Texting in US is Ripoff on D2 Updates, Text Message Notifcation · · Score: 1

    Actually, yes.

    I used to work for a company in Redmond *cough* that provides instant messaging and alerts via SMS, siphoning some of the carrier revenue that this generates.

    To avoid large amounts of *unexpected* SPAM over a newly created gateway from their IM clients or alert triggers to a cell phone subscriber, they require a new customer to accept (by responding to an initial SMS message) that they are willing to receive them.

  20. Re:can't buy a Dell PC w/o Windows -- bull! on Dell's Secret Linux Fling · · Score: 1

    Seems to me that you just proved the point that you were calling "bullsh*t" at the point in your story where you say "negotiate". "Negotiate" as in: one two minute phone call to our Dell rep. who was so quick to agree, that I had to make sure he understood what I was requesting. I wouldn't have spent more than 15 minutes trying to get a lousy $248 refund, anyway. It may have been that we did so much business with them that they'd not even blink over a louse $248, but my boss was in a nickel and dime mood that week and was quite happy that two minutes of my time got us $248 and established the principle that we didn't have to pay the MS tax on Dell machines we bought for Linux-based development.

  21. can't buy a Dell PC w/o Windows -- bull! on Dell's Secret Linux Fling · · Score: 2, Informative
    ...proved how hard it is to buy a PC from Dell without Windows.

    I call bullsh*t, or at least misinformation.

    I was able to negotiate a refund of some $62 for each of four Dell PC purchased while I worked at a former employer because we explicitly did not want Windows for them. Even though it came preinstalled, with shrink-wrap installation media, we got the refund upon returning the installation media and attesting that we reformatted the hard disk.

    Dell was not difficult about it.

    Of course, the fact that all our desktops were Dell machines, and most of them did run Windows, and my employer did have a blanket corporate license from Microsoft for all MS software may have had something to do with it, but still.

    Of course, getting a refund for returning something you don't want is not the same as not having to purchase it in the first place, but the bottom line was that, in the end, Dell happily sold us PCs with no operating system on them.

  22. Re:300 wires with a conduit sawed off on What Bizarre IT Setups Have You Seen? · · Score: 1
    1. The raceway was open, not closed, like a conduit. Sorry if I didn't make that clear.

    2. Ontario has some wierd codes. For example, it is not necessary to ground a satelite dish for lightning protection like almost anywhere else in North America, and IIRC, actually contrary to the electrical code to do so. Perhaps because a badly grounded antenna is worse than none at all, but that's why there are licensed electricians in the world.

    3. This building was wierd in other respects: not only was it necessary to use a card key to enter the building outside of normal business hours, or always, via non-main entrances, it was also necessary to use a card key to exit the building! Even at the main entrance (where the receptionist would "buzz" you out)! While there was supposed to be a failsafe to unlock all the doors for egress in the event of an emergency (fire, power failure, etc.), I was still amazed that this didn't seriously violate some building codes. Most of my coworkers did not find this odd, but I was shocked and somewhat uneasy because of it. I'd joke that I'd have no qualms throwing a chair through a main floor window to egress in the event of a fire if the exits were locked, and was reprimanded for thinking about "vandalizing the premises". Others told me, "Well duh! We'd all do it, but none of us is so stupid as to admit to it and get in trouble." Riiiight.

    Thankfully, I haven't worked there in over two years and have my green card to work and live in the U.S.

  23. Re:300 wires with a conduit sawed off on What Bizarre IT Setups Have You Seen? · · Score: 1
    Heh.

    When I worked for a large video card manufacturer in Markham, Ontario, we just moved into a new building.

    Well, plenum-rated Cat5e cable costs about three times what non-plenum rated cable costs, so instead of running plenum-rated cable in the false ceiling (technically a plenum), they ran the hideous metal cable raceways under a relatively nice false ceiling, so they could snake non-plenum cable in them.

  24. Re:Bad comparison, perhaps? on DVD Player Ownership Surpasses VCR Ownership · · Score: 1
    Another reason VCRs stick around is the accumulation of VHS cassettes many people (like me) tend to have.

    These fall into three catagories:

    • Licensed Content - we have lots of Disney movbies for the kids;
    • Recorded Content - we don't have much, but we have the odd home video (we don't take that many);
    • Gift Content - Grandma sends a cassette of something: an old movie recorded from analog TV (try explaining to Grandma about copyright) or a tape she made.

    As for recorded, and gift content, this tend to either rot into obnscurity or justify preserving in a different format.

    But, licensed content is another story, We (a) have a fair amount of it (around 50-100 cassettes), (b) don't want to relicense the same content on DVD at a high price, and (c) can't be bothered to transfer it to a different format.

    There is a market for content providers to issue "plain vanilla" DVDs (no scene navigation or extras) of previously issued VHS tapes. Heck, they could even add advertising. Such a disk should not cost more than $2-$3, and possibly require return of the original VHS cassette.

    I sure as heck don't find enough value in the extras and scene navigation to pay $20-$40 a second time for content I've already licensed. But, I do want the convenience of a smaller format, without the hassle of ripping the analog video myself.

  25. Re:Um, come again? on The Great Firewall of Canada · · Score: 1

    Not quite. He was convicted for "publishing false news". That law was later declared unconstitutional. The point is that he was not making false statements about an individual or identifiable group, but rather contradicting accepted history. Importantly, he was not advocating violence. Nevetheless, he was deported from the U.S. to Canada for overstaying a visa, Canada found the immigrant a threat to it's national security (he could have been deported for having let his landed immigrant status in Canada lapse because of his long U.S. stay) and deported him to Germany, where Holocaust denial IS a crime, and he was propmtly arrested. I disagree with his views but think he got a bum rap.