And in the current issue of Applied Physics Letters, a group led by Haroun Ahmed at the Hitachi Cambridge Laboratory in Britain reports another vital step, a single-electron transistor that, for the first time, amplifies its input signal (though only by a factor of 3.7, several hundred times more weakly than a conventional transistor does).

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That means that not only the signal input into the amplifier is symmetrical but also the signal output and therefore the connection to the headphones.

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More signal input subsequently equals a more secure position read-out, with the elderly base system offering initial location accuracy to around 100 meters.

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Forte features a colour OLED (Organic LED) display to indicate input and output signal levels, mic preamp gain and other useful information, with stylish motion graphics giving you detailed visual information.

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The advantage of digital input is that the signal sent by the PC doesn't have to be converted to analog, so signal loss is virtually eliminated, Fender said.

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The unique Loop Recorder also allows DJs to capture and overdub audio loops from the live mix, cue signal or an external input on the fly, and drop them back into the mix at any time.

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It feeds into a small computer with a video-input card that in turn sends the digitized signal via phone line to Deits' server.

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Input is just as unconventional: a Control Core turns NES-compatible gamepads into signal generators that can be used just as easily for music making as for playing.

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