I currently own a conn 100h and it’s become my main axe for almost everything, I’ve recently had a need to play a trigger horn and was wondering where I might take my horn to make the bell modular and if it would cost more than just buying a trigger horn?

I'm not sure how well a Conn 100H would work as a horn with an F attachment. What notes do you need to play down low that you can't hit with the 100H? Probably cheaper to just pick up a King 3B-F.

For that bore size, it would absolutely be more expensive than just buying an instrument with an F attachment already. I echo the question about what you are needing to play in that register, as that could change the recommendation,.

If you specifically want something that plays like a 100H and has a valve, though potentially cheaper than a conversion, a used 3B/F doesn‘t really fit that bill for me.

If you’re not too fussy about having the 100H feel, buying a used 3B/F, Reynolds or Olds might be cheaper.

There‘s forum member on here who had a plug-in valve section (tuning slide) made for his 48H and seems very happy with it. Might be an option?

I recently converted a King 2B into a modular horn for a customer. It ended up having a straight gooseneck and a rotor gooseneck that can be used as a G attachment or an F attachment. I can say with certainty that buying something like a King 3BF will be much cheaper than doing the conversion.

Did you take pictures of that one, Brian? Curious how you open wrapped a g attachment and made it modular. I imagine that was tricky due to how short the G tubing was!

The G tubing was not tricky at all. The two things that were tricky: 1. Finding a rotary valve that was the appropriate size (.512 bore)....I ended up ordering one from Jurgens Voight in Germany. 2. Finding a way to make the thumb lever and linkage move the valve efficiently. Actually, we are still working on that. I made a linkage, but it bumps the back of his left hand. So, he is bringing it back and we are going to try something different.

I am not much of a photo-taking person, but I did take a couple of photos along the way. The first photo shows the G-valve tubing, but the photo was before I placed a couple of cross braces on it and before I added the King thumb lever and linkage. Obviously, the F-attachment was simply an insert that would be placed in the tuning slide to extend it so it was about an inch longer than the main tuning slide. The second photo shows the King 2B with the straight gooseneck section beside it.

<LINK_TEXT text="download/file.php?mode=view&id=21931">https://trombonechat.com/download/file.php?mode=view&id=21931</LINK_TEXT>

<LINK_TEXT text="download/file.php?mode=view&id=21932">https://trombonechat.com/download/file.php?mode=view&id=21932</LINK_TEXT>

I DO NOT recommend converting a small bore horn in this manner. This horn ended up playing very well, but I think it is only because this particular King 2B (from the late 1960s) had a HUGE sound to start with and we just got a little lucky. This project was unusually labor intensive and some of the parts were tricky to find. My recommendation is to buy one of the small bore horns with F-attachment that is currently being offered.

Where did you end up attaching the valve bracing? I’m glad we went the direction we did with my project. Once you finish those slides I’ll have to let you loose in my 605F!

You should just copy the king style kidney linkage. You can cut it out of nylon or plastic like they used to do back in the days.

Then the trigger can be in a spot where the thumb can rest on the brace.

[quote="Matt K"]Where did you end up attaching the valve bracing? I’m glad we went the direction we did with my project. Once you finish those slides I’ll have to let you loose in my 605F![/quote]

The bracing was simple. I placed one between the two outer tuning slides of the attachment and then another between the outer tuning slide and gooseneck. On the F insert I had to use two more braces in order to keep it parallel. Keep in mind that nothing can be attached to the bell because it is modular.