Showing posts with label audio. Show all posts
Showing posts with label audio. Show all posts

Thursday, October 20, 2011

Piranhas Bark—Three Fierce Vocalizations Deciphered



Red-bellied piranhas (file picture) bark to warn away 
other fish, a new study says.


Piranhas, it turns out, can be excellent communicators, a new study suggests. But don’t get the idea they’re going soft—their barks, croaks, and clicks likely mean “leave me alone,” “I might bite you,” or “now I’m really angry!”



Researchers knew picking up red-bellied piranhas—among the few piranhas dangerous to humans—could prompt croaks from the fish. Even so, no one had studied their sounds in water or provided good evidence for the barks’ evolutionary role.

Now a fish tank, an underwater water microphone, and a video camera have helped uncover three different piranha calls—all tied to a variety of grumpy behaviors.

“We knew piranhas were able to make sounds but were not satisfied with the explanation for how they do it,” said biologist Eric Parmentier of the Université de Liège in Belgium. “We wanted to know how they do this and what these sounds might mean to other fish.”
(Piranha pictures: See the fossil “megapiranha” species.)                       More

Thursday, July 7, 2011

How to Build a Perfect Home Theater PC

How to Build A Slim, Stylish, Low-Power Home Theater PC
PCMag.Com - Suppose you’re interested in assembling a small, energy-efficient home theater PC (HTPC) that you’d also be proud to display in (or on top of) your entertainment center, but you didn’t want to invest huge amounts of time or money into making it happen. That’s reasonable—even die-hard builders with the best of intentions sometimes prefer to take a few shortcuts rather than reinventing the wheel every time a whim strikes. You can build exactly the HTPC you want—or almost any other kind of PC—in a dizzyingly short period of time by using a barebones kit.

These are kits by name vendors that give you the frameworks you need for a PC, but don’t fill in all the blanks for you. You may get one preloaded with a certain motherboard, for example, but the processor, RAM, video card, and any other components are left up to your discretion and budget. Using a barebones system helps you get the best of both the building and buying worlds: the satisfaction of doing a lot of it yourself along with the convenience of not having to fit every single piece of hardware into place (especially as many barebones systems are tiny or feature unusual interior configurations).

We decided to do something slightly different this month and see if we could satisfy our stylish-HTPC hankering by way of a barebones. The process would shorter and simpler than most builds—which is okay once in a while!—but would still net us a system we could be proud of. In doing all this, we were reminded that even a relatively simple build such as this one can present a few tricks or obstacles—and figuring out how to work with the exceptions always makes you better when you need to work within the rules.

Our starting point for our system was Zotac’s Zbox, a system that’s thinner and lighter than most college textbooks, but has a two-tone coloring scheme and elaborate LED design that makes it look better than any physics primer we ever lugged around during our university days. The AD03BR-U ($419.99) turned out to be exactly what we were looking for: It comes with a 1.6GHz E-350 motherboard/CPU combo from AMD; that should do for our modest needs. Plus, it’s got built-in Wi-Fi, which will reduce the number of wires we need to run to it, and an integrated Blu-ray drive for playing our high-definition movies. (The Zbox is more convenient and attractive than a lot of Blu-ray players out there.)

This didn’t leave us with a lot of other choices to make—in fact, we just needed to worry about storage and memory. We considered splurging on a solid-state drive (SSD), but wanted to keep the cost down. So instead we went with a 7,200-rpm 750GB Seagate Momentus ST9750420AS—that’s speedy for a 2.5-inch drive, and is a comfortable amount of space. The price was $79.99, with $10 off thanks to a special Newegg offer, so we liked its affordability, too. It also met another crucial requirement: It was only 9.5mm high—something that was necessary for it to fit into the Zbox case. (Other hard drives can measure 12mm, which is too thick for this application, as we’ll soon see.) To maximize performance, we knew we wanted to go all-out on memory. This meant 8GB, the most this system can hold, and we got that by way of a PNY Optima kit on Newegg; a $20 rebate got us the chips for only $54.99, a fine, low price.

And that’s it! Putting the system together doesn’t even take much more time than does plotting it all out. But because the process is more like upgrading a laptop than working on a traditional desktop, a little rethinking is required.