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From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: I want some loud horns
Date: Tue, 18 May 2004 01:09:42 -0400
Message-ID: <>

On Mon, 17 May 2004 07:49:51 -0400, "Jeff W" <> wrote:

>Try this.  Ouch, $700!

OUCH is right.  Effectively, an MP3 player and a couple of 30 watt burglar
alarm speakers.  $200 would be more in line.

If you want a REALLY loud horn for not much money, buy an emergency vehicle
electronic siren and use only the horn function.  Everyone has probably heard
the loud "GRONK" that fire trucks and ambulances make, usually as they're
going through a red light.  This is the horn function.  Most sirens have a
handy PA function too.

I mount the control box under the dash or in the engine compartment where the
controls are out of reach so that some cop can't accuse me of using a siren on
a civilian vehicle.  Very compact, behind-the-grille speakers are available,
commonly used on unmarked cars.

I have never paid more than $75 for a complete 100 watt setup.  Because the
larger departments tend to not reuse sirens when they trade vehicles, used
ones are common.  Two-way radio shops and ham fests are two good sources.

Funny this would come up.  Tonight I had just started installing a unit on my
new GMC/Izuzu MD truck.  I'm amazed that the japs would put such a wimpy horn
on a a real truck!


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: I want some loud horns
Date: Tue, 18 May 2004 17:05:41 -0400
Message-ID: <>

On 18 May 2004 19:46:06 GMT, (Mike Van Pelt) wrote:

>In article <>,
>GBinNC  <> wrote:
>>I wired in a separate button. There were lots of times I had
>>legitimate use for a horn but didn't want to scare everybody half to
>>death. I used the big ones sparingly <g>.
>I've often wished I had a special "YOU MORON!" horn ... I recently
>ran across a description of exactly the sound I want - "The sound
>of a 40-ton truck loaded with live pigs locking up the brakes at
>80 miles per hour."

Funny you'd mention that.  I designed a horn for a colleague just like that
back in the late 70s.  His description was "A Sand Mountain Pig wagon
careening down the hill with the brakes locked, the horn blaring and the pigs

We played around in a friend's studio (analog synthesizers) until we got the
sound he wanted.  I got a cassette tape with the audio.  I took it to work and
use a VERY expensive data acquisition system to digitize the tape while it was
played back very slowly (to accommodate the system's sample rate.)  From there
the sound file got edited byte by byte in a debugger until it would loop
seamlessly.  Then it was burned to EPROMs.  These eproms were driven by a
counter and they in turn drove a R/2R D/A converter resistor network that was
in turn connected to a siren PA microphone input.

This thing was brutally effective.  Lay on the "horn" and people turned and
ducked for cover.  It would scare me even when I knew it was coming.

Today it would be trivial to use something like Cool Edit Pro to construct the
sound file on a PC and then transfer it to one of the el-cheapo voice recorder
modules.  Feed the output of the module to a siren PA mic input and there you


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