2 horn sets on one tank - best setup?

Installation Help & Advice Horn Kits
1

I recently finished my upgrade. Now have a set of Shockers connected with 3/8" air hose to the Shocker 1/2" solenoid and a 7-gallon tank at 150 psi. It is great but I am missing the higher pitch sound of my old Omega AH-500 horn set. I like them both but separately they are each missing something. So I am thinking of installing the Omega horn set again to work with the Shocker set. Here are my questions:

  • The Omega AH-500 valve can only handle 120 psi. I don’t want to spend a lot of money on a new valve so I figured I could hook the Omega set up with a pressure regulator before the solenoid and cut that line down to 120 psi max. Will this work?

  • When running both horn sets off the 7-gallon tank, will this be enough air and psi to run them both at once? Or will the sound of both suffer?

  • If I can run them both off of the same tank, do I need to enlarge the 3/8" air line which runs to the manifold where the horn split will occur? If so then how large does it need to be?

Any advice?

2

Wow. You have one of the only 20 N3 horns ever made? Pretty impressive. But after listening to a sound recording of an N3 I would say it is a unique sound for a collector to enjoy, but not something I would want on my truck. To each his own. Here is a good link with photo and soundclip of the N3:

http://atsf.railfan.net/airhorns/n3.html

3

i want pics, with you and the horns together… lol if i get that ill be jealous

4

wow that n3 sound awesome!! how much will cost me to get that horn??? 1000+?

5

They should be fine running at the same time (horn wise). I can’t promise it’ll sound nice though. It may or may not… its something you’ll have to find out for yourself.

You should use a separate supply line for each horn so they have the flow they need. Otherwise you run the risk of them both suffering volume loss.

If you want to use a pressure regulator, you need to find one with high enough flow characteristics to power the horn. Unfortunately I can’t tell you what the AH-500 requires and am not a specialist on regulators, but I do know they can severely limit your flow though if you get the wrong one.

Pneumatic experts please chime in =)

6

hu hu… you said chime in…

7

Lol speaking on Jeremy and his “N3” I remember when he first bragged about having that and I wanted proof so he sent me a pic of a scalloped base M3… What a loser.

8

I did some more research and I believe I have found the solution to my initial question. It all comes down to the size of the air line and fittings along the main air path from the tank to the horns.

I was previously using rubber air hose with a 3/8" inside diameter (ID) so I figured I would have plenty of air flow however most of my fittings, couplers, manifolds, and adapters were 1/4" NPT so they had an ID even smaller than 1/4" in some places. This was restricting the air flow by quite a bit as you can see by the following values which show the cross-sectional area of the air flow channel inside the hose for the three most common hose sizes:

HOSE ID___AIR FLOW AREA (SQ. INCHES)____AIR VOLUME

1/2_______0.19635______________________100%

3/8_______0.11045______________________56%

1/4_______0.04909______________________25%

So you can see that I was dropping 44% of the airflow by using 3/8" ID hose instead of 1/2" ID hose, and then I lost another 31% (or more) of the airflow by using 1/4" NPT fittings. That is a total of 75% less air flow than I would have if I kept the entire air line at 1/2" ID!!!

So to me the answer was clear: replace my hoses and fittings to keep everything at 1/2" ID on the main line from the tank to the horns. I am going to install two horns but most of the time I will only fire one horn at a time, and both horns sound awesome when hooked up with 3/8" ID hose, so here is what I ended up with:

Everything is 1/2" ID hose and fittings from the tank to underneath the truck where I connect a 1/2" ID tee splitter. Each of the two splitter outputs step down to 3/8" ID hose which runs straight into the Shocker XL valves and then right into the horns. So I am able to run both horns off of just one air tank with a single 1/2" ID port and a single 1/2" ID hose which splits under the truck, then each horn receives half of the available air via dual 3/8" ID hoses. This will give me more air flow than I had before with a single horn, and I also have 7 gallons at 150 psi now versus my old 1 gallon at 110 psi. So it should work out great with more volume, longer duration, and choice of either horn or both! I am in the middle of the upgrade now and will post results in a few days.

One interesting note: it is not easy to find true 1/2" NPT fittings, couplers, quick disconnects, etc. Most stores only stock the more common 1/4" or 3/8" adapters and you need to keep everything 1/2" ID to preserve the high air flow volume. I finally found the Milton Type G 1/2" ID quick-disconnect couplers at Northern Tool & Equipment and these connectors are monsters! Each connector pair weighs about 1 lb. and when you release the coupler the male portion will fly about 2’ away from the spring power alone! But they do preserve the full 1/2" ID air flow up to 99 SCFM / 300 psi and they are super sturdy so I am feeling great about using them now.

I will post pics and a diagram of my finished setup soon. Had to wait until Monday for the second Shocker XL valve to arrive… :frowning: