Air Horns

[MG3610]

I'm looking for some info on air horns.

Does the length of the trumpet have any effect on the pitch of the horn?

KME has suggested Hadley Horns for our new engine. Anyone have any expierence with these?

Does the size of the air line have a direct effect on the "power" of the horn? I am assuming it does, if so what is the minimum air line recommended?

If each trumpet has its own air valve (teed off a main supply line), will the resultant sound be much louder?

Thanks in advance.

This is the pitch of horns we want. What factors make this distinct sound?

http://s153.photobucket.com/albums/s...t=DSCF1693.flv

[fire0099881]

that sounds like the same air horn's that are one our engine, I will find out for you what they are.

The thing that kind of bug's me about that video is when they turn onto the last street before the video stops, they don't even stop for the stop sign at a blind intersection.

[fireman4949]

Grover Stuttertone horns are perfect for fire apparatus.

http://www.airhorns.com/products.asp...&item=stutter#

[oledriver]

The one in the video sounds the short ones by grover. We have the short grovers, not happy at all. Find out the length. The length makes a difference. If Im not mistaken, I think Pierce uses Hadley. Not for sure. I was informed by pierce that they dont put to many grovers in there trucks.

[fireman4949]

The 1510 is the full length Grover horn.

I put one of these kits on my personal truck...
http://www.airhornsoftexas.com/image...510KIT_800.jpg

[westofd1]

we have grover sttutters on both kme customs as well as grovers on the kme commercial in our dept. like grovers never had any experience with hadley. good luck

[chiefengineer11]

We put Buells on our Spartan/Toyne. Go to www.buellairhorns.com. Bring up Fire, Police, EMS. The ones that appear there are what we spec'd. You can listen to them there, but the real thing sounds a lot better. I really wanted that five horn train set, but...., you know how that goes.

Stay safe out there, everyone goes home!

[boog8591]

MG3610,

On our new KME we spec'd Grover horns but KME recommended that we go with the Hadley instead because they claimed that the Grover horns were coming in yellowed from the factory and they have been having better luck with the Hadley.

I can tell you that the Hadley are definately loud, however do sound different than the Grover sound.

If you are in the area call me on my Nextel and stop by.

[HFRH28]

I believe these are the Hadleys, like we had on an E-One. Awesome sounding horn.... LOUD. I also like the buells, but at $290/horn... thats just outragous. We roun our ambulances with buells, mostly a pair of 1062s (the shorter, higher pitched horn found in the emergency series). This works fine, and works well. Above all, i still prefer the grovers, but buells and hadleys both get the job done. You don't want dual valves, at some $40-50 per valve. Get a GOOD valve! Our ambulances eat up cheap valves like crazy, so get a good quality valve. Each manufacturer could tell you what size line you need to feed the horns.

Edit: it always helps to add the link!
http://www.youtube.com/watch?v=oj5RA...elated&search=

[chiefengineer11]

MG3610,

On our new KME we spec'd Grover horns but KME recommended that we go with the Hadley instead because they claimed that the Grover horns were coming in yellowed from the factory and they have been having better luck with the Hadley.

I can tell you that the Hadley are definately loud, however do sound different than the Grover sound.

If you are in the area call me on my Nextel and stop by.

We were told by a chassis manufacturer that they were only using Grovers if the customer insisted on them. Otherwise they were moving toward Buell. The reasons that they gave were that the Grovers are coming in with very poor chrome, and that they are difficult to tune properly.

Many years ago I drove a tow truck that had Hadley horns on it. As small as they were, they did an impressive job.

Stay safe out there, everyone goes home!

[rschultzjr]

Our department is currently running two apparatus with Grover Stutter horns and we love them, they are loud and get attention when its needed. We are currently submitting a bids for a new truck and we specifically stated they had to be Grover Stutterhorns.

[npfd801]

We were told by a chassis manufacturer that they were only using Grovers if the customer insisted on them. Otherwise they were moving toward Buell. The reasons that they gave were that the Grovers are coming in with very poor chrome, and that they are difficult to tune properly.

Many years ago I drove a tow truck that had Hadley horns on it. As small as they were, they did an impressive job.
Stay safe out there, everyone goes home!

I second (or third) the comments that Grover has been delivering some very poorly chromed units. Not such a big deal where the horn is hidden under the bumper, but on commercial chassis when they're mounted to the side of a hood, a VERY big deal. The builder I rep for had this problem with Grover. I think they're using Hadley now unless Grover is specifically called out, but before I state this as fact I would need to go back through my notes.

Hadley makes some nice stuff, and I know they can make a horn to sound very close (if not spot on) to the Grover. I'd not hesitate to give them a shot. As a dealer rep, you meet these folks, and I really like the Hadley reps. You get a real good feeling who'll take care of you and who won't, and I would have no qualms with the Hadley folks. They make some pretty snazzy mirrors too (or own a company that does).

[MG3610]

Are the Hadleys tunable or is the sound "designed" into them?

So if the trumpet length has something to do with it, what effect does a short trumpet produce and what effect does a longer one produce?

I love that deep loud sound. Thats what we want for our rig.

Thanks for all the answers so far.

[thetatooisreal]

My department was 100% grover until our recent delivery. The pumper spec called for Grover but we agreed to change to Hadley at the pre construction. The pumper manufacture suggested the change and assured us we would be happier with the performance and sound on the Hadley horn. We changed to Hadley and absoulutly love the sound. It is deeper, rougher and meaner sounding than the grovers we were used to. We just got approved fo another pumper and have already wrote in the Hadley horns. To bad we didn't know about the Hadleys about 15 years ago, we could of had the whole fleet sounding good.

[Farmington2313]

On ALF units the standard size air line for the horns was 1/4". In '98 Charlotte ordered some Eagles and had in their spec to use 3/8" air line and the lines were to be the same length. The Charlotte units were alot louder than anything else we were building at that time. I was so impressed with the differance this cheap upgrade made that I changed all the air horn lines at the dept. I vol. with to 3/8".

[shiphorns]

To bad we didn't know about the Hadleys about 15 years ago, we could of had the whole fleet sounding good.

Hadley is a new player, they only started making "stuttering" emergency apparatus horns in May 2003, to try to take market share from Grover, whose 1510 horns have dominated this market for decades but with recent problems as noted above. Prior to 5/03, Hadley was making regular air horns for tractor trailers and heavy equipment, including rebadged OEM horns.

You can't tune the pitch of any of these horns, it's set by the physical dimensions of the trumpet, including the overall length, throat diameter and flare rate. Horns like the Buells that have fine tuning screws on the back are only for matching the diaphragm tension to the supply air pressure, the pitch is not significantly affected.

More air pressure and flow = louder, but don't exceed the manufacturer-recommended maximum pressure as measured at the inlet of the horn while blowing. Exceed the max, and you won't necessarily get instant failure, but you will get substantially reduced diaphragm lifespan and in some cases overblowing (squealing).