Newsgroups: rec.audio.tech
Subject: Re: Speaker damping
References:  
Larry Brasfield  writes:

> The reason to have low output impedance
> amplifiers is that they are easier to
> build and tend to be more efficient
> than amplifiers with controlled, non-
> zero output impedance, 

You can easily converta any zero outpu impedance amplifier
to a controlled output impedance amplifier by adding a series
resistor to the amplifier output. When the amplifier has zero
output impedance, the system output impedance with the extra
resistor is completely determined by the series resistor.
That series resistor looses more or less power determined
by it's value and amplifier power.

> combined with
> the fact that speakers are designed to
> be driven from such amplifiers.  Low
> impedance cables are way overrated.

You are right on this.

-- 
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
http://www.epanorama.net/