Re: OT: "Line level"
Posted by
Mike S-8 on
Jul 02, 2004; 5:47pm
URL: http://elecraft.85.s1.nabble.com/OT-Line-level-tp368401p368404.html
>--Original Message Text---
>From:
[hidden email]
>Date: Fri, 2 Jul 2004 07:30:49 EDT
>
>600 ohms is still very much the standard.
At 10:36 AM 7/2/2004, Jim Brown wrote...
>I believe you may be confusing voltage levels with impedance.
Analog phone circuits are indeed transmission lines. Try to feed a hybrid with an impedance mismatch and you'll get echo and sidetone problems.
Your reference to "pro audio" is a bit parochial - telco is the largest "pro audio" industry in the world, whether measured by number of employees, consumers, amount of revenue, whatever. Broadcast, studio and stage likely follow in that order.
You may be expert in your corner of "pro audio," but it's a much bigger world, and true 600 ohm audio transmission lines are still quite common throughout the world. The "line" in "line level" refers to telephone lines. Any other use is a misnomer - a broadcast engineer can call a 5v p-p signal "line level," but that usurpation of a well established term doesn't make it correct.
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