Thanks, both Paul and Jim for this information. Very useful and I'll update my knowledge base with it!
73, matt On Wed, 17 Dec 2008 08:45:53 -0800, you wrote: >On Wed, 17 Dec 2008 07:28:32 -0500, Paul Christensen wrote: > >>> "FWIW, standard Line Out is 1Vp-p at 600 ohms line impedance. matt" > >>I think you'll find standard, nominal "Line-In/Out" consumer levels to be >>referenced to -10 dBV irrespective of Z, where 0dBV = 1 Vrms. > >Yes. 600 ohms has not been part of audio practice, pro or consumer, for at >least 40 years. ALL line level and mic level audio circuits, pro and >consumer, are low impedance source, high impedance termination. The signal >is transferred as a voltage, not as power or current. Typical output >impedances are on the order of 100 ohms, input impedances are typically >10K for pro line level, 50K for consumer line level. 100 ohms is chosen >primarily because it is a good value for isolation of op amps from the >capacitance of the cable that it drives. This capacitance can be >significant in pro installations, but rarely in consumer applications. > >>This standard started with the old IHF, merged into EIA, and then >>somewhere along the way I believe AES became the recognized >>standard-setting organization in North America. K9YC would know > >I can't speak to the history of these standards, but The AES Standards >Committee is an international body, of which I am a member. > >>-10 dBV is equivalent to 0.316 Vrms. If we assume a worst-case 10 dB >>peak-to-average ratio (and probably a lot less depending on the K3's AGC >>menu settings), then the maximum distortion-free signal voltage handling >>required is 0 dBV or 1 Vrms or 2.83 Vp-p. > >Yes. > >For those who are interested, there's more on this in the tutorials on my >website. http://audiosystemsgroup.com/publish > >73, > >Jim Brown K9YC > > >_______________________________________________ >Elecraft mailing list >Post to: [email protected] >You must be a subscriber to post to the list. >Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > >Help: http://mailman.qth.net/subscribers.htm >Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
