going from 1/2" OD to 3/4" OD which translates to about .566" ID. Also upgrading the hoses to the individual horns from 3/8" OD to 1/2" OD.
I should’ve had these sizes in the first place but of course I didn’t know anything when I put this system together.
And here’s a few pics of my horn install/custom mounts
i’ll be getting rid of this fitting soon and making a “manifold” out of 1/2" NPT pipe fittings
Hey nice work and good job on making your own mounts.
Are you running the big air line all the way through from the tank and your valve? If so, I’d be interested in hearing your opinion on whether the switch to a 3/4 main line has made a difference.
I can open up on the K3 with two half inch lines coming from the tank in parallel, but have to say that it makes no difference whatsoever compared to opening a single valve.
P.S. Might want to get some anti-rust or fish oil on your earth wire there. Looks like some bad-a$$ corrosion starting to take hold in that last pic 
that corrosion is after only one winter too!! You aren’t kidding. Unfortunately some of my epic sound system got stolen and I removed the rest of it to prevent future theft, so those wires don’t serve a purpose anymore.
As far as the big air line, i’m going to run actual pipe (roughly 5/8" ID) from tank to valve, and then run the big airline from the valve to the manifold. I’m actually saving money this way by buying pipe instead of fittings, the 3/4" OD fittings are really expensive. I’ll try and get some pics up when i’m done, i’m leary of posting too many pics after my theft and all that but I really hope that no one on this forum is gonna come after my stuff!!
Nice upgrade & mounts. You can be sure that each horn is getting enough air. The 1/2" hard plumbed stuff is the ultimate. I had some 5/8" i.d. hose, but the fittings were smaller.
Sorry bout the stereo, I noticed all the grounds…
heck if I thought it was practical i’d run the 1/2" hard plumbed stuff all the way from tank to manifold…could get difficult though.
here’s a pic of the new manifold:
and i’ll be using similar stuff to attach the valve to the tank
i’m sure i’ve heard you talk about your sound system in a post on here somewhere so i really hope you garage your vehicle at night…just saying. My crap was stolen right from my driveway!
on the flip side, my stuff getting stolen pushed my to install the most obnoxious alarm system on my car that I could dream up which included a nathan k3…and that pushed me to this hobby which has been piquing my interest a lot lately. Funny how that works.
I think it’s a must when you want to protect your stuff.
well, the K3 has longer range than my paging alarm does anyways…ha
to my ears, these changes made a good bit of difference. Sounds nearly identical to the real thing now.
One small problem that I always had before, and still seems to persist - sometimes my #2 bell blows the wrong note. It’ll start off slightly higher than it’s supposed to, then if I leave it blowing long enough it’ll settle at the correct pitch in about 1 to 2 seconds. What could be the issue here? I think it’s getting enough air, and none of the other bells have this issue. Just that one.
Sounds like uneven flow or a leak around the diaphragm seat. How old are the horns? Try flipping the diaphragms over if it hasn’t been done yet. You’ll see the wear of the seat (i.e. a circular pattern) on the disc. If they’re clean on the opposite side, then just invert them. Make sure the bell has a good seal when you put the cap back on. If you can blow through it with your lungs then you might need new discs and/or cushion ring between the two diaphragms.
Read this, if you haven’t taken one of your horns apart yet:
http://www.microprecisiongroup.com/downloads/type_k_installation_maintenance.pdf
unfortunately I have no clue how old the horns are, i bought them used off ebay in early may.
When I did this upgrade to the fittings, I removed and disassembled the horns for cleaning. For all three horns, I moved the rear diaphragm to the front, and rotated it so the cleanest face was forward towards the horn throat. So in theory, that part of it should be solid.
Maybe those diaphragms are warped or something? I’m seeing this in the link you sent
“CHANGE IN CHARACTER OF SOUND: Cracked diaphragm disc. Warped diaphragm disc. All horns are
not blowing (Multi-tone models).”
Perhaps I could try swapping over the diaphragms and cushion ring from either the #1 or #4 bell, and see if the problem goes away.