Re: PA Question


William Black wrote:
> "No Busking" <nobusking@xxxxxxxxx> wrote in message
> news:MYCdnYDcSositRveRVn-tA@xxxxxxxxxxxxxxx
> > > Any PA will feedback more readily if cranked as high as it possibly
> > > will go.
> > >
> > > If you have a lot of power you won't need to crank the PA as far as it
> > > will go.
> > >
> > > You get it???
> > Um, yes, I get it, but you clearly don't.
> >
> > Care to explain to us what causes feedback?
>
> It's a 'runaway oscillator'.
>
> You've got an amplifier.
>
> To make it an oscillator all you need to do is feed some of the output back
> into the input and it will oscillate at its 'resonant frequency'.
>
> The resonant frequency varies depending on a number of factors.
>
> The trick with PA systems is to 'dial out' the room resonant frequency using
> a graphic equaliser.
>
> --
> William Black
>
> I've seen things you people wouldn't believe.
> Barbeques on fire by the chalets past the castle headland
> I watched the gift shops glitter in the darkness off the Newborough gate
> All these moments will be lost in time, like icecream on the beach
> Time for tea.

And also to have enough power so you're not running it past it's
optimal levels.

Chris

.

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