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Wireless Electricity Demo. New Biosensor Finds Bacteria In Seconds. A new project from Spain has created a means of detecting water borne bacteria in seconds. Drinking the water in a foreign country always seems like something of a gamble. Could be clean, could be a one way trip to spending the entirety of your vacation in the bathroom. Luckily, a research team at Rovira i Virgili University in Tarragona, Spain has developed a biosensor that can detect bacteria at levels as low as 1 cell per 5 mL of water. As reported in FECYT and SINC, the project utilized carbon nanotubes and fragments of DNA to detect Salmonella tyhpi, the bacteria that causes Typhoid Fever. And the best part? Water can be tested in just a few seconds. Bacterial infections may be an inconvenience to tourists, but they are down right deadly to third world citizens.
The biosensor works like a microscopic bacteria trip wire. It’s remarkable that the Salmonella biosensor can find a single bacterium in 5mL of water. KVG Laboratories. General Guitar Gadgets - Effect Kits & Parts. Acoustics Principles. For those looking to gain a deeper understanding of how audio works, whether to make better-informed decisions or simply for the sake of curiosity, it's useful to lay down some ground rules that govern how audio systems behave relating to loudness and the decibel.
One of the most important concepts in audio is the decibel, the unit of measure denoting the ratio of a change in level, whether that level is acoustic Sound Pressure Level (SPL) or electrical signal level. It’s abbreviated dB. As you may or may not be aware, the decibel (dB) scale is a logarithmic system, as opposed to a linear scale. Being aware of the relationships inherent in this scale is important for a variety of reasons, which will hopefully become clear by the time you reach the end of this article. We also discuss how the human hear perceives double loudness differently depending on frequency so +6dB increase in SPL may not seem like such a big deal at 1kHz but at 20-30Hz it certainly is.
Read on to find out why. ProSoundWeb Forums. The Welcome to the New PSW Forums! The New PSW Forums are now active. If you were a member of our previous forums, you will need to create a new username and password to access the new forums.Forums are moderated and users are required to register prior to posting. LAB Forums Forums include the LAB (Classic Live Audio Board), as well as LAB Lounge, Church Sound, Road Test, Installed Sound, Pro AV, and more. Topics related to sound reinforcement and application of audio, products and technology for live events. R/E/P Forums A wide range of forums devoted to the art and science of recorded audio, focusing on techniques, equipment selection and application, as well as topics such as mastering and production.
Church Sound Forums A community of information exchange for church sound practitioners and operators, also focusing on other important aspects of technical production as it relates to house of worship applications. Lighting Forums. Acoustic Reference. Build Your Own Clone - Guitar Clone Pedals. Understanding Compressors and Compression. Jan 1, 1999 12:00 PM, Barry Rudolph Compression is one of the most common processes in all audio work, yet the compressor is one of the least understood and most misused processors.
Compressed audio is an everyday fact of modern life, with the sound of records, telephones, TV, radios and public address systems all undergoing some type of mandatory dynamic range modification. The use of compressors can make pop recordings or live sound mixes sound musically better by controlling maximum levels and maintaining higher average loudness. It is the intent of this article to explain compressors and the process of compression so that you can use this powerful process in a more creative and deliberate way. Compressors and limiters are specialized amplifiers used to reduce dynamic range-the span between the softest and loudest sounds. THE BASICS There are four basic parameters on all compressors: compression ratio, threshold level, attack time and release time.
Acceptable Use Policy MixLine. How Technology Will Transform Us. The Future of Aging. Contact Lens? Or...Mouse?? This one’s kinda hard to swallow so take a deep breath, open your minds, and pretend it’s 2100. I CONTACT is essentially a mouse fitted to your eyeball. The lens is inserted like any other normal contact lens except it’s laced with sensors to track eye movement, relaying that position to a receiver connected to your computer. Theoretically that should give you full control over a mouse cursor. I’d imagine holding a blink correlates to mouse clicks. The idea was originally created for people with disabilities but anyone could use it.
Those of us too lazy to use a mouse now have a free hand to do whatever it is people do when they sit at the computer for endless hours. Designers: Eun-Gyeong Gwon & Eun-Jae Lee. The technology of Phase Shifters and Flangers. Copyright 1999 R.G.Keen. All rights reserved. No portion of these materials may be reproduced without written permission of the author. The technology of phase shifters and flangers Practically every guitarist has heard the swirling, spacey sounds characteristic of a phaser or its cousin, the flanger. These boxes have a unique sound that is immediately recognizable to us in rock and processed acoustic music. Unfortunately these effects are not the easiest effects to understand in terms of how that odd tone is made.
The terms "phase shift" and "flange" are not part of our daily lives, and don't really convey up any mental image that's useful in understanding them. What is phase shift? There is only a little electronics knowledge needed here. If we have another sine wave that is the same size and frequency but has different zero crossing times, it is said to be shifted in phase relative to the first wave. Take a little time...
This same result happens for higher frequencies. Phase up to it... Flanging. Origin[edit] As an audio effect, a listener hears a "drainpipe" or "swoosh" or "jet plane" sweeping effect as shifting sum-and-difference harmonics are created analogous to use of a variable notch filter. The term "flanging" comes from one of the early methods of producing the effect. The finished music track is recorded simultaneously to two matching tape machines, then replayed with both decks in sync. The playback-head output from the two recorders is mixed to a third recorder. The engineer slows down one recorder by lightly pressing a finger on the flange (rim) of one of the playout reels. The "drainpipe" or subtle "swoosh" effect "sweeps" in one direction, and the playback of that recorder remains slightly behind the other when the finger is removed.
Despite subsequent claims over who originated flanging, Les Paul discovered the effect in the late 1940s and 1950s, however, he did most of his early phasing experiments with acetate disks on variable-speed record players.