Beginner's capacitor question

Roy J. Tellason rtellason at verizon.net
Wed Apr 16 08:18:46 CDT 2008


On Wednesday 16 April 2008 01:34, Jochen Kunz wrote:
> On Tue, 15 Apr 2008 16:57:31 -0400
>
> "Roy J. Tellason" <rtellason at verizon.net> wrote:
> > > The capacitor simply eliminates the DC offset on the signal.
> >
> > Not the way he described it being connected,  across the speaker.
>
> Correct. I missread the original post.
>
> This is just a guess: If there is some series resistor (for current
> limiting) in line with the speaker, this resistor and the capacitor
> should construct some sort of low pass filter. I.e.: The speaker is
> driven with a square wave voltage that has many harmonics. The low pass
> filter can cut off may of the harmonics making a better "sound". The
> speaker, as beeing an inert mechanical system, has a low pass filter
> "build in".

That makes some sense to me...

And it's likely that there is a series resistor in there,  typical speaker 
impedances being on the low side and a bit much in terms of loading for the 
output of a TTL gate...

-- 
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space,  a critter that can
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Information is more dangerous than cannon to a society ruled by lies. --James 
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