Re: Speaker Mic - Common Base Config

As I said. You if can change the question you can change the answer to anything you desire. In logic, it's called a "strawman", or "red herring". That was *NOT* the question that was being asked.

Clueless. If the load is known (fixed) the maximum power delivered to the load will be when the source impedance is zero. *THAT* is the issue with audio amplifiers (the original question - apparently Alsheimer's is well settled in, in your house).

No, you're bringing in a red herring and pretending that it means something. Your logic sucks.

When the load is zero?

You're too old and senile to have any.

Indeed, and how sad. :-(

I haven't paid a lot of attention to his evolution but, lately, it seems to me that he's trying to attract attention to himself by pretending to authority in the realm of circuit design without actually presenting any schematics.

Well! That certainly fits the Larkin style ;-) ...Jim Thompson

Certainly at leaast half-wit ;-) ...Jim Thompson

-- [On the Road, in New York]

| James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at

Doesn't anyone know how to do a derivative? Oh! I forgot! You need a uP to do that ;-) ...Jim Thompson

The maximum power conjugate match thing only works in linear systems. Audio power amps and power plants aren't linear.

John

Of course you'll get the distortion products, but that's not the point. We were talking about power transfer, specifically matching a load to a generator.

Measure the output impedance of an audio amp, or better yet the impedance of an AC outlet in your house, and then apply the conjugate load. Keep a flashlight handy.

John

Can you believe that Larkin made such a statement? I guess he's trying to outdo his energy-is-not-conserved utterances. For some reason the world "village" keeps popping into my mind ;-) ...Jim Thompson

Naaaah, but he does strongly resemble a student I had at the college in an RF circuit desiign class who staunchly believed that an output designed to match to a 50R load would put out more power loaded with

Along about a week before the semester ended he came up and said he was now convinced that I was right, that matching DOES work that way. Maybe there is hope for krw at some point towards the end of this "semester".

Jim

Damn, Thompson, you've been on the New York road since I came through Phoenix on my way to Chicago the last week of June. You must have found the money pit back there.

Jim

Uncle John ...

Won't argue with you about the power plants; not my circle of experience. Audio power amps had damned well BETTER be linear or I've been doing it wrong for lo these many years.

Thanks,

Jim

Lying asshole. I have consistantly argued for the use of COE as a central axiom of design and analysis, and a major simplification in signal and circuit analysis. Do you use COE in signal analysis? I doubt it.

Do you actually think that audio amps are linear? That they have zero distortion? That you can apply a conjugate load and they'll work fine, follow JF's cute little table, at any signal level?

All sorts of nonsense seems to keep popping into your senile mind.

John

The world or word?

Jamie

It could happen. An RF power amp spec'd to drive a nominal 50 ohm load probably has a lower Zout than 50 ohms, so the maximum-power load could be below 50. The amp might get hot, of course, since its power supply and thermals weren't intended for that load.

Besides, RF amps have to be designed to handle all sorts of reactive loads and VSWR mismatches. Invoking the Maximum Power Transfer theorem can be an over-simplication.

Linear systems are simple. Once things get nonlinear, cases and explanations get complex.

John