condenser versus direct coupled?

Sean...From an electrical power point of view a square wave is the same as dc. The amount of power radiated in the form of sound would be trivial. True that cone motion with AC might tend to ventilate the driver. However, the oscillation would likely be at a frequency too high for the driver to respond, and therefore no significant cone movement would occur. I only claim that the damage potential DOES NOT DIFFER VERY MUCH, and that your "FAR greater" words were a gross exaggeration.

I was not involved with the DC transmission research, but I seem to remember hearing about 450 KV. If you are really interested in power transmission research results I will see what I can dig up and Email it to you. I guess we could check the web also. Some of the GE work was probably proprietary.

Sean...A quick check of the net suggests that 15 to 50 Kvolt transmission is considered "medium" voltage. 200 to 400 Kvolt is "high voltage". And this is for AC. I know that the research on DC transmission was at higher voltages than used for AC.

Sean...And furthermore... Furukawa Electric (Japan) has a 1,100Kvolt AC line in service, and a 500Kvolt DC UNDERWATER cable as well! WOW.

WOW is right!!! I guess you can learn something new every day. I'm obviously WAY out of touch with this aspect of "power delivery". Thanks for doing the legwork and correcting my screw-ups. Sean
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Sean...Now that we have called a truce, I will point out that my suggestion that an AC coupled power amp would oscillate might be challanged. If output transistors on one side blow, the result will be a DC output, just like a runaway DC coupled amp. However, I do think it is true that DC amps generally have protective circuitry.