Re: Speaker Kill Switch

["Robert L Bass" <robertlbass@xxxxxxxxxxx>]

"Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote in message
news:cZCdneFf-eJDWj3ZnZ2dnUVZ_oCdnZ2d@xxxxxxxxxx
> "E. Lee Dickinson" <lee@xxxxxxxxxxxxxxxxxxxxx> wrote in message
> news:e7nmj4$f78$1@xxxxxxxxxxxxxxxxxxxx
>> I have a cluster of outdoor speakers on an impedance-matching volume
>> control.  One speaker points directly towards the neighbor's house. I
> would
>> like to be able to selectively kill that one speaker.
>
> What kind of impedance matching control and brand/model of amp are you
> using?  FWIW, any control you build for that speaker should probably be
> operable remote by your neighbor as well.  I can see instances arising
> where
> you might not realize the speaker's powered up and your neighbor might
> want
> to power it down.  And that's even if you're on the best of terms.
> Accidents happen.  Especially if it's X-10!  Jim would sleep better, I'm
> sure, knowing that your neighbors were properly empowered to silence your
> potentially hostile audio emissions.  <big grin>
>
>> Can I put a switch (immediately a waterproof outdoor light switch,
>> ultimately an inline module) in line with the positive wire of the
> speaker?
>
> Depends on your impedance matching control.  It should automatically
> adjust
> for the speaker being taken in and out of the circuit.  As long as the
> switchover occurs quickly, there shouldn't be an issue.
>
> Many years ago, when I was considering distributing audio at speaker
> instead
> of line level (now I use dedicated amps in each room), I was told you
> should
> use a make-before-break double pole DT switch and use a dummy load so that
> you don't expose the amplifier to transients or have it running at high
> volumes without a load.  The dummy load would also tend to keep the volume
> level at the other speakers more constant.

Bobby,

That's old information.  Modern consumer amps are not adversely affected by
operating with no load.  Some of the old stage amps would blow their finals
if you disconnected the load while they were operating at high volumes but
that won't likely be an issue for his residential gear.

As to make-before-break, that's still important when you're swapping line or
mic level sources but not for speaker loads.  Since he's only interested in
killing the sound to a speaker it's a complete non-issue.  In fact, several
of the more popular makes (i.e., Russound, Niles Audio) of impedance
matching volume controls are offered paired with an A/B speaker selector
switch that does not make before break.  Some clients even use the A/B as an
On/Off switch so they can leave the volume at a given level when switching
the room sound on or off.

--

Regards,
Robert L Bass

=============================>
Bass Home Electronics
4883 Fallcrest Circle
Sarasota · Florida · 34233
941-866-1100 Sales & Tech Support
http://www.bassburglaralarms.com
=============================>