100SILEX, de 0 à 100 s: Single
1522 5 Simple steps to secure TT-RSS reader
secure tt-rss, tt-rss security
5 Simple steps to secure TT-RSS reader
July 27, 2015 by Anand Leave a Comment
Share: share htpcBeginner
We recently presented Tiny Tiny RSS to you as a great alternative to Google reader, which is one more way you can extend the functionality of your home server or your hosting space. Hopefully, you already exported your data from Google Reader. In this post, we will show you how to secure TT-RSS reader to prevent unauthorized access. Tiny Tiny RSS is an open source web-based news feed (RSS/Atom) reader and aggregator, designed to allow you to read news from any location, while feeling as close to a real desktop application as possible. As we previously explained, it makes an ideal candidate to replace Google Reader. While there are services like Feedly and Newsblur grabbing the crowd Google Reader, which some of you may prefer, there are a group of people who would like to run a RSS reader on their own server and keep things private. Assuming that you have already installed Tiny Tiny RSS on your alternative to Google reader or hosting space, we will now show you how to secure TT-RSS reader.
Secure TT-RSS Reader
One of the main reasons to move to an RSS aggregator like TT-RSS is maintaining your privacy. So if you do not secure TT-RSS reader well you are not only making your data available public but also making your system vulnerable to potential attacks. Choosing a strong username and password while setting your TT-RSS is the first basic thing that you can do to secure TT-RSS reader. Listed below are few more ways you can increase TT-RSS readerâs security.
1. Rename TT-RSS Folder
One of the first lines of defense is to not use tt-rss in your URL to access your TT-RSS reader. To do this on your hosting account, use a folder name other than tt-rss while installing TT-RSS. On your Linux home server, edit /etc/tt-rss/apache.conf and change the first /tt-rss to something else. An example is shown below.
TT-RSS Rename URL
TT-RSS Rename URL
After making the change, restart your TT-RSS and Apache to apply the changes:
sudo service tt-rss restart
sudo serivce apache2 reload
Your TT-RSS reader is now available through the new URL (example: http://mydomain.com/myreader) only.
Amazon Kindle Fire HDX
2. Enable SSL
Accessing TT-RSS through http sends all information as unencrypted data. This could mean less privacy due to potential sniffing. The solution is to encrypt the data during transfer, which makes sniffing by hackers harder. To enable and enforce HTTPS access on Linux servers with Apache, install the following run-time libraries:
sudo apt-get install libssl0.9.8 libpam0g openssl
Restart your Apache server as shown above. You should now be able to access your TT-RSS reader with HTTPS. Note that you may have to have a SSL certificate generated. Refer to Apache documentation if you want to generate your own certificate. By default, the system will install self-signed certificates for you. These certificates are likely to raise warnings when you point your browser to the site.
3. Disable Single User Mode
By default the single user mode is already disabled (in /etc/tt-rss/config.php). Enabling single user mode will also disable TT-RSS login system. Therefore, keep the single user mode disabled.
Disable Single User Mode
Disable Single User Mode
A better way to make it a single user system is by limiting the number of registrations to 1 as described below. For whatever reason, you still want to enable single user mode, make sure you implement Apache Authentication method described below.
4. Self Registrations
Self registrations allow a visitor to register themselves, which could reduce TT-RSS security. If your TT-RSS will be for personal use only, then you may want to disable user registration by setting âENABLE_REGISTRATIONâ to âfalseâ.
TT-RSS Self Registrations
TT-RSS Self Registrations
To further secure TT-RSS Reader, uou may also want to change âREG_MAX_USERSâ to â1â to make your account the only account on TT-RSS.
asus n66uASUS RT-N66U Dual-Band Wireless-N900 Gigabit Router
asus n66u reviewsFind out why it is rated the best wireless router in its class.
5. Apache Authentication
Last but not the least, enable Authentication. This is even more important if you have enabled âSingle User Modeâ describe above. Every time you access TT-RSS, you will be asked for a username and password as shown in the picture below:
Secure TT-RSS Reader
On your hosting account this equivalent to password protecting a directory, in this case the TT-RSS directory. To do this on your Ubuntu server, you will have to create a .htpasswd file. More information is available in Apache documentation. But the easiest way to achieve this is to use one of the htpasswd generators available online.
After you enter the username and password two code blocks will be generated. Copy the contents of the .htpasswd code block and save it to /etc/apache2/.htpasswd_ttrss. Next, copy the contents of the .htaccess code block and add it to /etc/tt-rss/apache.conf as shown below:
TT-RSS Apache Authentication
TT-RSS Apache Authentication
Save and exit. Restart both TT-RSS and Apache previous shown above. You should be prompted for a password every time you try to access TT-RSS. Some may think that this double authentication method is an extra inconvenience. But I would rather be safe than sorry.
Go ahead, secure Tiny Tiny RSS Reader and enjoy reading articles on your private secure RSS Reader.
1305 12 Volt Power Supply - 3.5 Amp Single Output
A 40W 12V/3.5A Highly Reliable, Universal AC input/full range single output power supply.
power supply, switching power supply, switch-mode power supply, UL approved, RoHS , enclosed power supply, low cost, single output, DC power supply, AC to DC poer supply, RoHS directive, 12 volts, AC to DC, modular eurorack monorocket psu
1122 Disk Wiping - One Pass is Enough - Part 2 (this time with screenshots) | Anti-Forensics
Demonstration of what happens to data with a single pass wipe using EnCase, WinHex and the HDD Wipe tool.
disk wiping, erase data, erase hard drive, encase, winhex, magnetic force microscopy
1093 Disk Wiping - One Pass is Enough - Part 2 (this time with screenshots) | Anti-Forensics
Demonstration of what happens to data with a single pass wipe using EnCase, WinHex and the HDD Wipe tool.
disk wiping, erase data, erase hard drive, encase, winhex, magnetic force microscopy
1052 Lab Overview
Not that I recommend this level of excitement to everyone, but this is my lab. It is my basement, and as you may note from the disheveled ceiling tiles up above, having this much equipment has actually forced me to purchase a separate AC unit for the basement. So my trendy two-zone AC house has now magically become a three-zone AC house. Fortunately, I didn't need a furnace for down here. Equipment is great in the winter to heat your house!
The lab has taken on a life of it's own over time... It started out as a single standard 7-foot 19" rack. Then it grew to two standard racks... Then it changed into three Ortronics Mighty-Mo 19" rack systems (because those are cool). As seen now, it has changed yet again into four separate rack cabinets. The cabinets are a bit pricey, so they aren't all the same vendor. Note to all, even if you find a really good price on Ebay, be aware that you still have to ship them, and they weigh a LOT! (This means, have lots of friends and lots of pizza/beer!)
Nov'04 -- Well, things have moved even more! The equipment was beating the AC unit that ran for the basement. So instead of being a three-level, three-zone house, we had to upgrade to being a four-zone house. Go figure. As noted above, I would not recommend this path to anyone unless you have a good amount of business to drive it! All of the equipment here is used for testing and lab purposes, but easily serves as Proof of Concept lab for many consulting clients of mine. The recent change was that the crawlspace area under the kitchen area was excavated out and had a concrete floor poured making an enclosed little room. In addition, a large air handler (AKA Mongo AC Unit) was put into that specific room and a door was installed for access and physical separation! While all a very interesting project, it is a pain to move any equipment that you amass, so definitely plan ahead for this sort of activity!
948 Pixel Perfection When Rotating, Pasting And Nudging In Photoshop - Smashing Magazine
When creating Web and app interfaces, most designers slave over every single pixel, making sure itĂąÂÂs got exactly the right color, texture and position. If youĂąÂÂre...
web design, magazine, html, photoshop, wordpress, wallpaper, icons
889 IBM - Watson
Watson, the IBM computer that will compete on Jeopardy!, represents an impressive leap forward in analytics and systems design. The underlying DeepQA architecture is designed to find the meaning behind a question posed in natural language and deliver a single, precise answer.
IBM, Watson, Jeopardy!, Thomas J. Watson, DeepQA, smarter planet, Watson Buzz, Jeopardy! Challenge, supercomputer, NLP, natural language processing, What is Watson?, analytics, Jeopardy! countdown, system design, industry transformation, research IBMers
I have started to build a (slightly) updated version of the Korg PS-3200 synthesizer.
The PS-3200 was the last of three fully polyphonic, semi-modular analogue synthesizers offered by Korg in the late 70's. (See Ben Ward's excellent Korg PS site for detailed information, including user manuals.)
The concept of the PS-Synthesizers was different from other manufacturer's early polyphonic instruments. Instead of using a small number of voices and a clever keyboard assigning circuit, the "PolyKorgs" had a complete synthesizer circuit, hard wired to each key. That makes a total of 48 VCFs, 48 VCAs and 48 voltage controlled ADSRs even for the smallest of the range, the PS-3100. The largest of the range, PS-3300, even had 144 of these circuits.
The sheer number of synthesizer circuits called for an extremly economic circuit design, and it's a joy to look at Korg's design ideas which led to building blocks that almost did the same as in the better known "classic" synthesizers. And after many years of engineering and reverse-engineering electronic music circuits, I have learned to look at odd solutions not as "substandard", but as a source of creativity an individual character. Here's a list of some highlights:
Function Implementation Side effects
Single-Transistor Waveform Converter creates triangle, saw, pulse and PWM from saw input, using one (!) transistor, one diode and two resistors per voice, plus two global control voltages Pulse height also changes with pulse width
5-Transistor-VCF (Korg-35) A Voltage controlled 2-pole (Sallen&Key) LPF built from 5 transistors rather high CV feedthru
Single-Diode VC Resonance The dynamic resistance of a simple diode is used to alter the feedback gain of the VCF limited range of Q
"Expand" function instead of VCF Envelope modulation depth Instead of scaling down the ADSR with a VCA, the a variable portion of the Envelope is just clipped with a single diode. It's so remarkably close to ordinary VCA function that apparently nobody takes notice. At least I have not read about it anywhere.
At slow Atack times, the Envelope appears delayed at the VCF (no effect until th eclipping point is reached). Usefull for Brass sounds, and not easy to emulate with conventional synthesizers.
Minimum parts count Voltage Controlled ADSR Three transistors, 1/2 of a LM324 and one CD4007 per voice. Plus some more involved control circuit, shared by several voices Transistors must be selected in 13-tuples, not just in pairs.
ADSR detail (1):
One-opamp control logic 1/4 LM324 is used as Flipflop, which is dynamically set by Gate-ON, dynamically reset by Gate-OFF, statically reset when the attack peak voltage is reached, and whose set/reset sensitivity is altered by a CV Very odd "Hold" function, depending on the "Attack"-value. But very useful in practise.
ADSR detail (2):
Single-Transistor, exponential slope VC-Decay Using a single transistor per voice for VC Attack and Release is remarkable already, even though the A and R slopes are linerar. But the Decay slope is exponential, and this is achieved with a single transistor and two resistors per voice! The Decay time range is rather limited. No ultra fast Decay, and no ultra slow Decay either.
Single-Transistor VCA That's the "Korg standard" VCA, well known from other instruments like the MS-10.
What an amazing instrument! The DSI Evolver has the signature "old school" timbre down pat as well as being able to provide digital timbres reminiscent of the Waldorf Q. There's certainly a "rougher" side available as well with all the feedback implementation and controled distortion. Being able to make PM type plucked and blown sounds is just icing on the cake. Dave Smith should be commended for a job well done. Just have a look at the Panel Layout to get a taste of what this beauty can dish out - the controls are pretty much laid out in the form of a signal path graphic. Be sure to visit Dave Smith's Website!
Evolver Sound Examples
There are a lot of demos of the Evolver on the web showcasing the gutsy harsh sounds of this beast so I decided to post demos of some of my own patches as examples of the "softer" more "vintage" side of the Evolver's timbre. I make no apologies for these unpolished recordings - these are merely sound samples ;)
Resonant Plucked Pad
This pad shows some of the rich resonant nature of the filter.
This is a simple analog brass lead patch.
A fun patch with lots of motion made using my "Audio-rate Filter FM" programming tip below.
A nice bland-vanilla pad ^_^
What can I say? I love pads...
For more MP3 demos showing the full gamut of sounds the Evolver and Polyevolver are capable of, please visit the excellent website of Stefan Trippler!
The Definitive Guide to Evolver
This rather in-depth guide to the Evolver goes places and does things a mere manual can't. This labor-of-love was crafted by Anu Kirk and with his kind permission, I am offering this fantastic resource right here in PDF format!
A much smaller version (400K) is here but it dosen't have internal hyperlinks.
Here's a fun repository of programming tips for the Evolver in all its incarnations. Please email me if you would like to add some.
Fingered Wave Sequence
Submitted by Dave Bryce. This brilliant technique has to be heard to be believed! Plus, its one of those cool things unique to the Evolver! This particular tip is so full of detailed information that it gets its own page!
Audio-rate Filter FM
Submitted by James Maier. Use the "Audio Mod" parameter in the Filter section to frequency-modulate the cutoff with the analog oscillator. Add resonance until the filter is just on the edge of oscillation then mod the cutoff with just a little triangle LFO set at a very slow speed. Amazing moving chorusing pad and lead sounds can be made this way.
Fatter Bass/Pad Sounds
Submitted by Mike Peake. Set the same sound in both channels (detuned saws, for instance). With the filters at the 24dB setting, increasing resonance cuts the passband as on the Moog filters. Set Envelope 3 to minimum attack, maximum decay and release, and sustain to maximum. This "creates" an offset, a continuous "on" signal while the keys are gated. Modulate one filters' resonance up (just one), or of the overall resonance level is high, us it to modulate one filters' resonance to its minimum. You get the resonant character plus the size of the non-resonant filter. Use Tri and Sine waves on that side too.
Submitted by James Maier. The Evolver can make many ultra-bright and buzzy sounds due to its extensive feedback and distortion stages but sometimes people miss the subtler side of the beast. For a warmer sound use little or no distortion, close the filter just a bit and turn off the feedback and delay lines. I've managed to get dead-on Prophet5 timbres this way.
Submitted by Mike Peake. Set the envelopes to linear, and use a Mod to modulate AmpEnv All by itself (lin through log responses with positive and negative self-modulation).
This is of course fun on the filter envelopes as well.
More Vintage Character
Submitted by Mike Peake. Oscillator Slop, set at 5, doesn't come close to the Moog and other old-timer movement, so add slight (1 or 2) LFO to pitch modulations, with individual LFOs per oscillator, and a touch of LFO to LFO rate modulation. A tad of Envelope 3 to pitch helps as well.
Don't miss out on the 12dB filter setting
Submitted by Mike Peake. The 24dB setting has much more resonance, but the 12dB setting can sound nice and plucky, and do nice slightly fuzzy pads etc.
DSI Evolver Waveshape Charts
Below are charts I've assembled of the digital waveforms and their spectra as currently used in the DSI Evolver synthesizers. Originally these waves were unique to the SCI ProphetVS vector synth.
I find these waveform/spectra graphics really usefull when programming sounds - maybe you will as well. Pay special attention to the spectra as this info is sometimes much more useful than waveshape in determining actual timbre - even before you hear what the waveform sounds like.
These are designed to be downloaded (right-click & "save target as"), and printed at 300dpi on 8.5" x 11" pages - don't resize these images before printing or you will lose useful detail. Use them as a handy refrence. This information was cobbled together from various scattered sources (with very special thanks to Achim Gratz!).
Any errors or omissions are my own. ^_^
As far as the origin of these waves is concerned, one of the original VS engineers, Chris Meyer, said:
"The original waves for the VS were created three ways - extracting single-cycles from sampled sounds, using a custom additive synthesis program, and using a program Josh (Josh Jeffe, another VS engineer) slapped together called "Hacker" where you could draw the waveshape. These were fed straight from the computer through the filter and VCA of a Pro-One to figure out what they might sound like in a patch. And by the way, no PPG waveforms appear inside the VS - we had access to them, but in the end our consciences got the better of us. We did steal some waveforms from the Korg DW6000, but only by looking at the harmonic drawings on the front panel and trying to imitate them in our additive synthesis program."
Modulation Matrix "Cheat Sheet"
This chart shows all the modulation routing available on the Evolver. This same info is available in the manual but this can be printed on a single sheet of paper as a handy refrence!
These I created just for fun and desktop "beautification" ;)
1280 X 1024
1024 X 768
800 X 600
767 The 5 types of programmers Â« Steven Benner's Blog
In my code journeys and programming adventures Iâve encountered many strange foes, and even stranger allies. Iâve identified at least five different kinds of code warriors, some make for wonderful comrades in arms, while others seem to foil my every plan.
However they all have their place in the pantheon of software development. Without a healthy mix of these different programming styles youâll probably find your projects either take too long to complete, are not stable enough or are too perfect for humans to look upon.
The code may not be pretty, but damnit, it works!
This guy is the foundation of your company. When something goes wrong he will fix it fast and in a way that wonât break again. Of course he doesnât care about how it looks, ease of use, or any of those other trivial concerns, but he will make it happen, without a bunch of talk or time-wasting nonsense. The best way to use this person is to point at a problem and walk away.
You want to do what to my code?
This guy doesnât care about your deadlines or budgets, those are insignificant when compared to the art form that is programming. When you do finally receive the finished product you will have no option but submit to the stunning glory and radiant beauty of perfectly formatted, no, perfectly beautiful code, that is so efficient that anything you would want to do to it would do nothing but defame a masterpiece. He is the only one qualified to work on his code.
Iâm a programmer, damnit. I donât write code.
His world has one simple truth; writing code is bad. If you have to write something then youâre doing it wrong. Someone else has already done the work so just use their code. He will tell you how much faster this development practice is, even though he takes as long or longer than the other programmers. But when you get the project it will only be 20 lines of actual code and will be very easy to read. It may not be very fast, efficient, or forward-compatible, but it will be done with the least effort required.
What do you want? It works doesnât it?
The guy who couldnât care less about quality, thatâs someone elses job. He accomplishes the tasks that heâs asked to do, quickly. You may not like his work, the other programmers hate it, but management and the clients love it. As much pain as he will cause you in the future, he is single-handedly keeping your deadlines so you canât scoff at it (no matter how much you want to).
Well, thatâs a possibility, but in practice this might be a better alternative.
This guy is more interested the options than what should be done. He will spend 80% of his time staring blankly at his computer thinking up ways to accomplish a task, 15% of his time complaining about unreasonable deadlines, 4% of his time refining the options, and 1% of his time writing code. When you receive the final work it will always be accompanied by the phrase âif I had more time I could have done this the right wayâ.
Personally, Iâd have to classify myself as the perfectionist. So, which type of programmer are you? Or perhaps you know another programming archetype that is missing from my list? Post a comment below and Iâll add it to a new updated list.
718 Musiques - H O R S N O R M E
Dossier : OĂč trouver de la musique sur internet ?
Par Ed End le samedi, mai 29 2010, 10:07
fĂȘte de la musique
oĂč trouver de la musique
I. Pourquoi chercher de la musique sur internet ?
Pour rĂ©pondre Ă cette question on peut se poser une autre question : OĂč trouver de la musique en dehors d'internet ?
A part quelques exceptions Ă Paris, la plupart des disquaires indĂ©pendants ont disparus. Les supermarchĂ©s ont trĂšs peu de choix. Les magasins spĂ©cialisĂ©s, par exemple la Fnac ont un nombre limitĂ© de rĂ©fĂ©rences disponibles Ă des prix pas toujours accessibles.
Cependant il reste des solutions intĂ©ressantes : le marchĂ© de l'occasion, acheter les albums lors des concerts Ă des prix plus abordables ou encore moins onĂ©reux les emprunter Ă des mĂ©diathĂšques. Convertir en mp3 les anciens supports, k7, cd, vinyles et Ă©changer des albums numĂ©risĂ©s dont on dĂ©tient les originaux, lĂ©galement, dans le cadre de la copie privĂ©.
Si malgrĂ© cela tant de personnes cherchent de la musique sur internet, c'est :
a. Parce qu'il y a beaucoup plus de choix.
A l'heure actuelle, par exemple, le dĂ©veloppement de la musique libre est tel qu'il est impossible de suivre l'intĂ©gralitĂ© des Ćuvres qui sont publiĂ©es.
b. Parce que le coĂ»t est quasi nul.
- Soit en raison de la disparition du support, il n'y a plus de coĂ»t de diffusion, plus de coĂ»t de fabrication, juste Ă©ventuellement un coup de crĂ©ation. MalgrĂ© cela dans le domaine commercial les magasins en ligne (Itune et autres consorts) sont loin de rĂ©percuter la disparition des coups sur leurs tarifs.
- Soit en raison de ce que les lobbys et le gouvernement appĂšlent piratage, pour ma part je considĂšre qu'ils font une faute d'orthographe et prĂ©fĂšre parler de partage. Un exemple flagrant de leur mauvaise foie, contrairement Ă ce qu'a prĂ©tendu un jour un patron de la Fnac, un album n'est pas une baguette de pain, passer l'Ă©tape de crĂ©ation du premier exemplaire, il est duplicable Ă l'infini, ni farine, ni travail supplĂ©mentaire, autrement dit, je ne connais aucune baguette de pain qui puisse nourrir toute la planĂšte.
c. Parce que la dĂ©couverte est facilitĂ©e.
Depuis que les majors ont pris le contrĂŽle des mĂ©dias radio et tĂ©lĂ©, Ă part dans de rares mĂ©dias papiers spĂ©cialisĂ©s, et certains gratuits culturels, c'est trĂšs difficile de faire des dĂ©couvertes. ConcrĂštement avec un logiciel de peer to peer, on Ă©tend trĂšs rapidement la diversitĂ© des musiques que l'on apprĂ©cie. DĂ©jĂ pour la simple raison que dans tous les genres, au-delĂ du mainstream des majors il existe des Ćuvres de qualitĂ©.
d. Pour pouvoir essayer la musique avant de l'acheter.
Une bonne faĂ§on de se prĂ©munir des singles qui pourraient permettent d'Ă©couler des albums bĂąclĂ©s.
706 Geometry, Surfaces, Curves, Polyhedra
POV-Ray: A Tool for Creating Engaging Visualisation of Geometry
Various notes on polygons and meshes
Includes Surface (polygon) simplification, Clipping a polygonal facet with an arbitrary plane, Surface Relaxation and Smoothing of polygonal data, Mesh crumpling, splitting polygons, two sided facets, polygon types.
Philosophy is written in this grand book - I mean universe - which stands continuously open to our gaze, but which cannot be understood unless one first learns to comprehend the language in which it is written. It is written in the language of mathematics, and its characters are triangles, circles and other geometric figures, without which it is humanly impossible to understand a single word of it; without these, one is wandering about in a dark labyrinth. Galileo (1623)
Distance between a point, a line and a plane
The intersection of a line with another line (2D)
The closest line between two lines (3D)
The intersection of a line with a plane
Mathematics describing a plane
The intersection of two planes
The intersection of three planes
Polygon area and centroid calculation
Inside / outside polygon test
Reflection of a ray
Eulers number and closed surfaces
Determining whether a line segment intersects a facet
Coordinate transformations on the plane (2D)
Cartesian, Cylindrical, and Spherical
Euler angles and coordinate transformations
Converting between left and right coordinate systems
Clipping a line with a polygon
Clockwise test for polygons in 2D
Test for concave/convex polygon in 2D
Area of (planar) polygons in 3D
Spheres, equations and terminology
The intersection of a line and a sphere (or a circle)
Equation of the circle through 3 points
Equation of the sphere through 4 points
Intersecting area of circles on a plane
Rotation of a point about an arbitrary axis
Creating a plane/disk perpendicular to a line segment
Intersection of two circles on the plane
Circumference of an ellipse
Intersection of two spheres
Distributing Points on a Sphere
Quadric equations in x and y of degree 2
Fowler angles: Comparing angles without trigonometry
Description of an efficient contouring algorithm as it appeared in Byte magazine. (Byte Magazine, 1987) and a more general approach for arbitrary contour planes and polygonal meshes.
Methods for mapping points on a spherical surface onto a plane, stereographic and cylindrical (including Mercator) projections. Includes Aitoff map projection: Conversion to/from longitude/latitude (spherical map)
Classification of projections from 3D to 2D and specific examples of oblique projections.
A triangle was an improvement to the square wheel. It eliminated one bump. BC comics
Planar (stretching) distortion in the plane
Including Anamorphic projections and Mappings in the Complex Plane (Otherwise known as Conformal maps)
Polygonising a scalar field
Otherwise known as marching cubes and marching tetrahedrons.
A Macintosh 4 dimensional geometry viewer and manual.
533 The Theory and Technique of Electronic Music
Sinusoids, amplitude and frequency
Measures of Amplitude
Units of Amplitude
Synthesizing a sinusoid
About the Software Examples
Wavetables and samplers
The Wavetable Oscillator
Audio and control computations
The sampling theorem
Converting from audio signals to numeric control streams
Control streams in block diagrams
Audio signals as control
Operations on control streams
Control operations in Pd
Automation and voice management
Linear and Curved Amplitude Shapes
Continuous and discontinuous control changes
Encapsulation in Pd
Taxonomy of spectra
Multiplying audio signals
Frequency and phase modulation
Pulse trains via waveshaping
Pulse trains via wavetable stretching
Movable ring modulation
Phase-aligned formant (PAF) generator
Time shifts and delays
Time shifts and phase changes
Recirculating delay networks
Power conservation and complex delay networks
Variable and fractional shifts
Fidelity of interpolating delay lines
Taxonomy of filters
Low-pass and high-pass filters
Band-pass and stop-band filters
Elementary non-recirculating filter
Non-recirculating filter, second form
Elementary recirculating filter
Real outputs from complex filters
Two recirculating filters for the price of one
One-pole low-pass filter
One-pole, one-zero high-pass filter
Peaking and stop-band filter
Stretching the unit circle with rational functions
Butterworth band-pass filter
Impulse responses of recirculating filters
Single Sideband Modulation
Fourier analysis and resynthesis
Fourier analysis of periodic signals
Periodicity of the Fourier transform
Fourier transform as additive synthesis
Properties of Fourier transforms
Fourier transform of DC
Shifts and phase changes
Fourier transform of a sinusoid
Fourier analysis of non-periodic signals
Fourier analysis and reconstruction of audio signals
Timbre stamping (classical vocoder)
Phase relationships between channels
Symmetries and Fourier series
Sawtooth waves and symmetry
Dissecting classical waveforms
Fourier series of the elementary waveforms
Square and symmetric triangle waves
General (non-symmetric) triangle wave
Predicting and controlling foldover
Sneaky triangle waves
Sound synthesis and sound design
Music has brought pleasure and entertainment to mankind throughout the whole of history. Each person is by nature equipped with one of the most elaborate and emotional musical instruments; the human voice. Whenever people feel good music seems to fit the occasion, and it is considered quite natural to hum or sing a song. Musical instruments have brought their own moods to music and at the current moment in human evolution there is an enormous variety of musical instruments available. The twentieth century has seen the development of a range of new and exciting electronic musical instruments. These electronic instruments are very flexible, they can produce a wide range of timbres and can be amplified to whatever loudness level sounds best for the occasion. Most of these electronic instruments are played by a keyboard, but in essence the keyboard can be replaced by any electromechanical device that is able to transform a movement caused by a human interaction into an electrical signal that can drive the sound generating core of the electronic instrument.
All sorts of technical and scientific developments have helped to create electronic instruments and the human interface to play them. Still, music is an art and not really a hard science, although music and sound have for a long time been subject to various scientific research. An important realization is that science can not really explain why much music is such a pleasure to listen to and such a joy to make. Which is not a bad thing, as probably no one is waiting for science to take the fun out of music by applying formalized rules and templates on what is also subject to âfeelâ. So, although this book covers techniques that lean heavily on scientific research, the application of these techniques will in general be aimed at creating fun. There are a lot of professionals working with sound and even more people that make music for their personal enjoyment. Mastery of sound synthesis is valuable to all of them. Still, it wonât be easy to please everyone with one single book, as some people will be more interested in how things work and others might want practical examples that just work. The aim of this book is that it can at least be used as a practical guide in workshops and courses in electronic music, covering some essential basics that are needed to operate the equipment used in sound synthesis in a way that makes some sense. Additionally it can be used to explore techniques to find out how they can help in the development of oneâs own musical style.
Sound synthesis is the art of creating sounds by using suitable electronic means, using either analog or digital electronic devices. Sound design is the art of creating particular sounds using sound synthesis techniques. The definition of sound design as used here might be confusing to some, as the name sound design is also used in the discipline in industrial design that occupies itself with how mass produced objects should sound. Examples are how the sound of cars or ladyshaves are âdesignedâ to sound pleasing while in use. Which of course has nothing to do at all with music or sound synthesizers. This book puts the emphasis on the various synthesis techniques for musical purposes and how to setup sound synthesizers to create a large range of characteristic musical sounds. The art of musical sound design is left to the artist.
484 Why did so many successful entrepreneurs and startups come out of PayPal? Answered by Insiders
Why did so many successful entrepreneurs and startups come out of PayPal? I long have been fascinated by the extraordinary achievement from the ex-Paypal team and wonder about the reasons behind their success. In the past, mass media tried to answer this question several times but still couldnât give us a clear answer.
I once asked David Sacks the same question during an event in Los Angeles. He told me the secret is that Paypal has built a âscrappyâ culture. No matter what problems they faced, they would find a way to solve them. I kind of got the idea, but was still confused about the execution details.
So when I saw some of the past Paypal employees answering this question on Quora, I was super excited! After all, they should be the only ones who can tell people the inside stories.
Below are some highlights of their answers. *If you want to check out the sources or leave your comments, please go to here and here.
On Talent Management
âPeter and Max assembled an unusual critical mass of entrepreneurial talent, primarily due to their ability to recognize young people with extraordinary ability (the median age of *execs* on the S1 filing was 30). But the poor economy allowed us to close an abnormal number of offers, as virtually nobody other than eBay and (in part) google was hiring in 2000-02.â (by Keith Rabois, former Executive Vice President of Paypal)
âExtreme Focus (driven by Peter): Peter required that everyone be tasked with exactly one priority. He would refuse to discuss virtually anything else with you except what was currently assigned as your #1 initiative. Even our annual review forms in 2001 required each employee to identify their single most valuable contribution to the company.â (by Keith Rabois, former Executive Vice President of Paypal)
âDedication to individual accomplishment: Teams were almost considered socialist institutions. Most great innovations at PayPal were driven by one person who then conscripted others to support, adopt, implement the new idea. If you identified the 8-12 most critical innovations at PayPal (or perhaps even the most important 25), almost every one had a single person inspire it (and often it drive it to implementation). As a result, David enforced an anti-meeting culture where any meeting that included more than 3-4 people was deemed suspect and subject to immediate adjournment if he gauged it inefficient. Our annual review forms in 2002 included a direction to rate the employee on âavoids imposing on othersâ time, e.g. scheduling unnecessary meetings.â (by Keith Rabois, former Executive Vice President of Paypal)
âRefusal to accept constraints, external or internal:We were expected to pursue our #1 priority with extreme dispatch (NOW) and vigor. To borrow an apt phrase, employees were expected to âcome to work every day willing to be fired, to circumvent any order aimed at stopping your dream.â Jeremy Stoppelman has relayed elsewhere the story about an email he sent around criticizing management that he expected to get him fired and instead got him promoted. Peter did not accept no for answer: If you couldnât solve the problem, someone else would be soon assigned to do it.â (by Keith Rabois, former Executive Vice President of Paypal)
âDriven problem solvers: PayPal had a strong bias toward hiring (and promoting / encouraging, as Keith mentions) smart, driven problem solvers, rather than subject matter experts. Very few of the top performers at the company had any prior experience with payments, and many of the best employees had little or no prior background building Internet products. I worked on the fraud analytics team at PayPal, and most of our best people had never before done anything related to fraud detection. If heâd approached things âtraditionallyâ, Max would have gone out and hired people who had been building logistic regression models for banks for 20 years but never innovated, and fraud losses would likely have swallowed the company.â (by Mike Greenfield, former Sr. Fraud R&D Scientist of Paypal)
âSelf-sufficiency â individuals and small teams were given fairly complex objectives and expected to figure out how to achieve them on their own. If you needed to integrate with an outside vendor, you picked up the phone yourself and called; you didnât wait for a BD person to become available. You did (the first version of) mockups and wireframes yourself; you didnât wait for a designer to become available. You wrote (the first draft of) site copy yourself; you didnât wait for a content writer.â (by Yee Lee, former Product & BU GM of Paypal)
On Culture & Ideology
âExtreme bias towards action â early PayPal was simply a really *productive* workplace. This was partly driven by the culture of self-sufficiency. PayPal is and was, after all, a web service; and the company managed to ship prodigious amounts of relatively high-quality web software for a lot of years in a row early on. Yes, we had the usual politics between functional groups, but either individual heroes or small, high-trust teams more often than not found ways to deliver projects on-time.â (by Yee Lee, former Product & BU GM of Paypal)
âWillingness to try â even in a data-driven culture, youâll always run in to folks who either donât believe you have collected the right supporting data for a given decision or who just arenât comfortable when data contradicts their gut feeling. In many companies, those individuals would be the death of decision-making. At PayPal, I felt like you could almost always get someone to give it a *try* and then let performance data tell us whether to maintain the decision or rollback.â (by Yee Lee, former Product & BU GM of Paypal)
âData-driven decision making â PayPal was filled with smart, opinionated people who were often at logger-heads. The way to win arguments was to bring data to bear. So you never started a sentence like this âI feel like itâs a problem that our users canât do Xâ, instead youâd do your homework first and then come to the table with â35% of our [insert some key metric here] are caused by the lack of X functionalityâŠâ (by Yee Lee, former Product & BU GM of Paypal)
âRadical transparency on metrics: All employees were expected to be facile with the metrics driving the business. Otherwise, how could one expect each employee to make rational calculations and decisions on their own every day? To enforce this norm, almost every all-hands meeting consisted of distributing a printed Excel spreadsheet to the assembled masses and Peter conducting a line by line review of our performance (this is only a modest exaggeration).â (by Keith Rabois, former Executive Vice President of Paypal)
âVigorous debate, often via email: Almost every important issue had champions and critics. These were normally resolved not by official edict but by a vigorous debate that could be very intense. Being able to articulate and defend a strategy or product in a succinct, compelling manner with empirical analysis and withstand a withering critique was a key attribute of almost every key contributor. I still recall the trepidation I confronted when I was informed that I needed to defend the feasibility of my favorite âbabyâ to Max for the first time.â (by Keith Rabois, former Executive Vice President of Paypal)
âExtreme Pressure â PayPal was a very difficult business with many major issues to solve. We were able to see our colleagues work under extreme pressure and hence we learned who we could rely on and trust.â (by Keith Rabois, former Executive Vice President of Paypal)
464 Ksplice Â» Attack of the Cosmic Rays! - System administration and software blog
Itâs a well-documented fact that RAM in modern computers is susceptible to occasional random bit flips due to various sources of noise, most commonly high-energy cosmic rays. By some estimates, you can even expect error rates as high as one error per 4GB of RAM per day! Many servers these days have ECC RAM, which uses extra bits to store error-correcting codes that let them correct most bit errors, but ECC RAM is still fairly rare in desktops, and unheard-of in laptops.
For me, bitflips due to cosmic rays are one of those problems I always assumed happen to âother peopleâ. I also assumed that even if I saw random cosmic-ray bitflips, my computer would probably just crash, and Iâd never really be able to tell the difference from some random kernel bug.
A few weeks ago, though, I encountered some bizarre behavior on my desktop, that honestly just didnât make sense. I spent about half an hour digging to discover what had gone wrong, and eventually determined, conclusively, that my problem was a single undetected flipped bit in RAM. I canât prove whether the problem was due to cosmic rays, bad RAM, or something else, but in any case, I hope you find this story interesting and informative.
92 John Snow sur MySpace Music - Ecoute gratuite de MP3, Photos et clips vidĂ©os
Profil MySpace Musique de John Snow. TĂ©lĂ©charge des singles de John Snow Pop / Rock / Power pop, regarde des clips vidĂ©o, Ă©coute des mp3 gratuits et lis le blog de John Snow.
rencontre amis ĂÂ©couter musique gratuite artistes exclusivitĂÂ© clips vidĂÂ©os fan
32 Charts in France | Bienvenue
Portail musical franĂ§ais d'actualitĂ© musicale, de classements (Top50), clips, plus de 80 000 artistes rĂ©fĂ©rencĂ©s et une communautĂ© de milliers de membres.
101 - 201