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Re: OT: "Line level"

Posted by Mike S-8 on Jul 02, 2004; 1:13am
URL: http://elecraft.85.s1.nabble.com/OT-Line-level-tp368401p368417.html

At 07:44 PM 7/1/2004, [hidden email] wrote...
>When an input to, or output from an audio device is specified as being  "line
>level", what exactly does that mean? Is it a specific RMS voltage perhaps?  
>Its a term that I've heard bandied about over the years but either never knew,  
>or have forgotten the precise meaning.

A "line out" signal is one which provides a nominal .775 V RMS signal (1 mw into 600 ohms = 0 dBm). Peak level is usually +4 dBm, or about 1.23 volts. It has nothing to do impedance, where it's connected internally, or whether or not there's a means of level adjustment (all things sometimes incorrectly associated with the term).

Any signal source which provides, or can be adjusted to provide, that level output can properly be called a "line out."

The term "line" originates in telephony, and later broadcast audio (here's a reference: http://www.richardhess.com/be/aes-80.htm ).

Mike

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