July 2003 - cypherpunks-legacy

Re: Idea: The ultimate CD/DVD auditing tool (meow)
by Tyler Durden 10 Jul '03

10 Jul '03

"Then your ears are not golden, period." Harumph! But you misunderstand what the phase button does. If the speakers are wired out of phase anybody can hear that. Actually, it's a quite interesting thing to hear...nothing is really localizable. But the phase button inverts the absolute phase of the signal coming out of both speakers. In other words, with a bass drum hit do the speaker cones move outward at the initial strike or inward (as they are not supposed to). Supposedly this difference can be heard, but my speakers start rolling off below 100Hz, so I suspect that's why I have a very hard time discerning the absolute phase difference when I hit the button. -TD >From: Jim Choate <ravage(a)einstein.ssz.com> >To: <cypherpunks(a)einstein.ssz.com> >Subject: Re: Idea: The ultimate CD/DVD auditing tool (meow) >Date: Wed, 9 Jul 2003 23:51:47 -0500 (CDT) > >On Wed, 9 Jul 2003, Tyler Durden wrote: > > > Somebody wrote... > > > > >Yes this is for localization ---clicks are broadband, you need to > > >identify which freq components are used. I still think > > >humans can't discriminate the phase of a tone. > > > > An interesting thing to try is to play with the "phase" button on many > > high-end gear. This supposedly matters for low frequencies, but despite >my > > unarguably golden ears, I'm still not convinced I can hear the >difference. > >Then your ears are not golden, period. > >A standard test of audio systems in PA's for example is related to >'speaker phase' (ie all the cones move out or in together at the same >time). This is tested by putting a click on the line and then standing >between pairs of speakers. It is quite easy to tell when the speakers are >in phase. The same can be said for music (and no you don't need expensive >high end equipment), garble the phase and things like echo become very(!!!) >wierd. You just have to have the experience to know what to 'look' for. > >A very(!) simple test to demonstrate/test your phase sensitivity (using >even very low quality equipment) is to connect a speaker between the R and >L channels (in essence it is driven by diff between the two channels). >This tends to highlight the phase disparity between the two channels >significantly enhancing the 'depth' of the music. Put a switch in there >and then have a friend enable/disable the speaker without your knowledge. >Then indicate what you think is the 'third speaker' setting. If you can't >tell nearly 100% of the time then any money on high end equipment is a >waste of your budget. This trick (was very popular in the 70's, especially >for us Quadraphonic fans) was what eventually led to the sub-woofer we all >know and love today (I do wish somebody would do something about those >damn rattling cars though). > > > -- > ____________________________________________________________________ > > We are all interested in the future for that is where you and I > are going to spend the rest of our lives. > > Criswell, "Plan 9 from Outer Space" > > ravage(a)ssz.com jchoate(a)open-forge.org > www.ssz.com www.open-forge.org > -------------------------------------------------------------------- _________________________________________________________________ Help STOP SPAM with the new MSN 8 and get 2 months FREE* http://join.msn.com/?page=features/junkmail

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Dizzy over Lizzie (Metro Times Detroit) - Student finds new method to factor quadratics (fwd)
by Jim Choate 10 Jul '03

10 Jul '03

http://www.metrotimes.com/editorial/story.asp?id=5077 -- ____________________________________________________________________ We are all interested in the future for that is where you and I are going to spend the rest of our lives. Criswell, "Plan 9 from Outer Space" ravage(a)ssz.com jchoate(a)open-forge.org www.ssz.com www.open-forge.org --------------------------------------------------------------------

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The Register - RFID Spy-chippers leak confidential data on the web (fwd)
by Jim Choate 10 Jul '03

10 Jul '03

http://www.theregister.co.uk/content/55/31654.html -- ____________________________________________________________________ We are all interested in the future for that is where you and I are going to spend the rest of our lives. Criswell, "Plan 9 from Outer Space" ravage(a)ssz.com jchoate(a)open-forge.org www.ssz.com www.open-forge.org --------------------------------------------------------------------

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we jammin, we hope you like jammin too
by Major Variola (ret.) 10 Jul '03

10 Jul '03

U.S. satellite feeds to Iran jammed http://www.msnbc.com/news/936772.asp?0cv=CB10 (Note that the "difficulty" of finding the jammer is disinfo... the NRO / NSA knows *exactly* where the jammers are, probably the color of their hats. Note that the US fomenting civil war with its agitprop is only mentioned obliquely.)

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Re: Idea: The ultimate CD/DVD auditing tool
by Tyler Durden 10 Jul '03

10 Jul '03

Tim May wrote... >Most so-called high end tube amps do in fact sound different, perhaps >"better," perhaps not. This is of course because tubes are usually rich in >odd-order harmonics. That $4000 Krell tube amp is actually _coloring_ the >sound. So much for 20-bit DACs in the signal source: the amp is altering >the sound at about the 6th or 8th or whatever most significant bit. A couple of corrections, then the comment. First is that tubes boost the even order harmonics, making the sound much richer and fuller sounding. Also, the Krell is digital, not tube. But your point is correct, but also well-known within audiophile circles. In fact, single-end triode style tube amps (which hit the market about 10 years ago) have really rotten measureables, but they have continued to grow in popularity because of the the allegedly "live/lush" sound. (Another odd thing about them is that they have extremely low output powers--12W, 8W and 6W are common!) Everyone knows they are basically nearly random tone-control gizmos, but no one cares at this point. As for 24/96 (or 24/192), like I said there are real engineering reasons for doing this, but in the end there's not much reason to argue if you haven't heard. Go listen to a standard CD played on an upsampling machine and you will know in no uncertain terms that the sound is considerably better/fuller/realler. (A hint as to why can be seen when you look a square wave reproduced in 16/22 vs 24/96.) As for audiophile voodoo there's a lot out there, but there's a pretty easy way to differentiate voodoo from real (though 'inexplicable') high-end stuff. The voodoo dissappears within a year or two, but the real stuff keeps going. -TD A PS about double-blind: There's been lots of them done, some confirming audiophile expectations some contradicting. Some of the disparity is due to who the blindees are: high-end listening is a skill that is basically self-taught. Some of the high-end tweeks have differences that are not discernable to nonGolden ears (and some tweaks are obviously pure snakeoil). _________________________________________________________________ Add photos to your messages with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail

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Re: Idea: The ultimate CD/DVD auditing tool (meow)
by Tyler Durden 10 Jul '03

10 Jul '03

Somebody wrote... >Yes this is for localization ---clicks are broadband, you need to >identify which freq components are used. I still think >humans can't discriminate the phase of a tone. An interesting thing to try is to play with the "phase" button on many high-end gear. This supposedly matters for low frequencies, but despite my unarguably golden ears, I'm still not convinced I can hear the difference. My Thiel speakers, however, claim to be "phase coherent", and that seems to be an entirely different matter. In other words, the different frequency components of a sound are transmitted in correct phase relationships (ie, true to the original sound), and the result is a (sometimes) astonishing level of spacial detail. Of course, non-audiophiles will poo-poo that claim, but even they will hear that the Thiels are far more accurate than the crap that's sold in Circuit City or whatever. So I figure I may as well believe Jim Thiel's claim that phase coherence is important in a speaker. -TD >From: Mike Rosing <eresrch(a)eskimo.com> >To: "cypherpunks(a)lne.com" <cypherpunks(a)lne.com> >Subject: Re: Idea: The ultimate CD/DVD auditing tool (meow) >Date: Wed, 9 Jul 2003 14:32:53 -0700 (PDT) > >On Wed, 9 Jul 2003, Major Variola (ret) wrote: > > > Yes this is for localization ---clicks are broadband, you need to > > identify which freq components are used. I still think > > humans can't discriminate the phase of a tone. In fact, MP3s > > use this to cut bits. > >They can tell relative phase, but it takes a lot of training. > > > After the experiments, the cats > > will be ok, as I assume they're sufficiently > > plastic, unless you do brain staining on them. :-( Or your policy is > > the > > Tim McVeigh treatment. > >both. They spend a year training the cats, then a year or 2 collecting >data, then brain stain, then vaporize. Each cat is worth about $1M when >it's all done, and it's got a lot of skull missing while it's alive. >But it's well protected with a lot of aluminum and epoxy :-) > > > Cool stuff, though my domestic feline wants to know where you live. > > > > PS: have you identified the "can opener sound" brain-center yet? > >I think you better keep it far away! And no, they don't play with >higher order systems. The low level stuff is hard enough!! > > > Cats manage biometrics and reputation better than most human systems.. > >:-) > >Patience, persistence, truth, >Dr. mike _________________________________________________________________ Help STOP SPAM with the new MSN 8 and get 2 months FREE* http://join.msn.com/?page=features/junkmail

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Slashdot | Russians Order Mobile Phone Encryption Removed (fwd)
by Jim Choate 10 Jul '03

10 Jul '03

http://slashdot.org/articles/03/07/10/0036232.shtml?tid=158&tid=99 -- ____________________________________________________________________ We are all interested in the future for that is where you and I are going to spend the rest of our lives. Criswell, "Plan 9 from Outer Space" ravage(a)ssz.com jchoate(a)open-forge.org www.ssz.com www.open-forge.org --------------------------------------------------------------------

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Slashdot | Webcaster Alliance Threatens To Sue RIAA (fwd)
by Jim Choate 10 Jul '03

10 Jul '03

http://yro.slashdot.org/yro/03/07/09/2037258.shtml?tid=123&tid=99 -- ____________________________________________________________________ We are all interested in the future for that is where you and I are going to spend the rest of our lives. Criswell, "Plan 9 from Outer Space" ravage(a)ssz.com jchoate(a)open-forge.org www.ssz.com www.open-forge.org --------------------------------------------------------------------

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pegasus
by netkita＠earthlink.net 10 Jul '03

10 Jul '03

How do i use my privite and public keyrings to encrypt email. I think that I have the file part and then use as an attatchment ok Thanks

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[9fans] security hole (fwd)
by Jim Choate 10 Jul '03

10 Jul '03

---------- Forwarded message ---------- Date: Wed, 9 Jul 2003 20:07:05 -0400 From: David Presotto <presotto(a)closedmind.org> To: 9fans(a)cse.psu.edu Subject: [9fans] security hole I plugged a security hole in Plan 9. It involved the state of a process after it did a newns(). Newns() is used to create a new namespace, usually after a process has changed uid (like when someone attaches to a server: telnet, ssh, ...). Newns opens a file, called a namespace file, that describes the new namespace and then follows the instructions inside (see /lib/namespace). Newns(2) creates a new namespace, but until the process calling newns does a chdir through /, it's local directory is still in the old name space. If the process then navigates the name space using relative commands (chdir(".."), open("../lib/profile")) it is walking the space using the priviledges of the OLD user id. Because of the way namespaces are usually set up, this doesn't normally happen. All the normal namespace files themselves do a chdir to /usr/$user effectively leaving the old namespace before newns returns. However, if either there wasn't such a chdir in the namespace file, i.e., if you've removed it for your installation or /usr/$user (and also /usr/none) doesn't exist then it was possible for a user to log in (for example via telnet or ssh) and end up in a directory like /usr/bootes in which they still had the rights of bootes. Neither situation applied to the labs since we have a /usr/none but one user in Japan (YAMANASHI Takeshi <uncover(a)beat.cc.titech.ac.jp>) discovered it when he created an account with no home dir. I changed newns() to fix the problem. It now always leaves you chdir'd into a directory in the current namespace. It does that by first seeing if the namespace file has already caused a chdir through the root. If not, it effectively does a chdir(getpwd). If that fails, it does a chdir("/"). This is a change in semantics. I haven't found (by inspection) any programs that would be bothered by it but please tell me if you see anything fishy since I'm about to update sources with the change. I've been running our servers here with the change for a few days and all seems well.

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