Mirafone 186 Intonation Issue

[TubaTed]

Hoping to get some advice on a nagging intonation issue on an older Mirafone 186 Bb, built in 1969.

The fourth rotor plays 20-25 cents sharp, with the slide completely pulled out. The horn does not seem to show signs the 4th rotor and assembly was ever messed with. The rotor is aligned to factory notches.

Anyone else have this issue and can help?

Thanks!

Ted

[cjk]

Does your King have the problem too?

Did you measure the lengths of the fourth valve tubing between the King and the Mirafone to see if there is a difference?

You should probably just take the thing to a repairman. You probably just need the 4th slide to be longer.

[Dan Schultz]

Question: does your 186 have the original bell? Sometimes switching from a recording bell to an upright bell makes for some 'interesting' pitch changes. Is the branch directly after the main tuning slide original? Mirafone 'messed with' the length of the main slide and that branch to resolve pitch issues between the use of recording and upright bells.

Going on....

The slide on the 4th circuit is so short, I can see where there might be problems if the player normally plays toward the sharp side, anyway. About the only thing I use the 4th slide on a Mirafone for is any 1-3 combination BELOW the staff so I've not noticed it much.

Miraphone has been known to make that 4th circuit a bit longer by incorporating a slide that has a 'return' loop on it. If you can work out a reasonable compromise between other fingering compromises or pulling the main slide out a bit.... you might consider having a longer 4th slide built.

Mouthpiece combinations can also make a difference. I was playing a 186 this morning that I just reassembled. The horn was playing on the flat side with my normal MF3. The horn performed better with a Stofer-Geib.

[TubaTed]

Great info. Thank you!

Does Miraphone really have a 4th valve tuning slide with a return loop? How to get one?

Problem with the horn is that the slide cannot be made longer. It will hit the inside of the body.

I typically play with the main tuning slide mostly out. The horn is inherently sharp, but the fourth valve is not making it easy for me.

I'm playing it with a G&W Diablo and a Jupiter Sousa bit. I know the bit may sound stupid, but I can center the tuning needle with it on open tuning Bb. It's also very comfortable. Don't judge.

[TubaTed]

I think it has the original upright bell. The main tuning slide branch may have been modified. The leadpipe was screwed with and appears shortened. That's why I use the Sousa bit.

[Dan Schultz]

....Does Miraphone really have a 4th valve tuning slide with a return loop? How to get one? Problem with the horn is that the slide cannot be made longer. It will hit the inside of the body....

I don't know if Mirafone made a slide with a 'return' on it. But... I've seen them on the 4th wrap of a 186. Could have been custom made. Nevertheless.... your slide can be converted into one with a 'return' by buying two more crooks and fabricating some ferrules. I've attached a picture on a custom slide I just made for my King rotary. In my case... the 3rd circuit was horribly flat and I needed to eliminate some tubing. I did not want to sacrifice the original circuit so I made the new slide.

[TubaTed]

That's cool Dan! Thank you for sharing!

[Beans&Tuba]

My 186 has a return loop on its fourth valve slide. It was made in 1966 I believe.

[Bob Kolada]

Fwiw, Miraphone has a (not advertised) replacement 4th valve tubing edit replacement with a long pull for the 191. It wouldn't hurt to send an email asking if they have something similar for your horn.

[TubaTed]

Hey Beans&Tuba! Can you please post a pic of the slide in the horn with some basic specs?

Looks like I'm heading in the direction of having a slide built.

Thanks!
Ted

[Beans&Tuba]

I have been unsuccessful in posting images. It says that the file is too large.Sorry I'm not very computer savvy.

[Dan Schultz]

I have been unsuccessful in posting images. It says that the file is too large.Sorry I'm not very computer savvy.

Some folks post the image to a 3rd party server and link to the image.

I have found the easiest thing to do is simply open the image in MS-Paint and resize the image to less than 256K. Click on 'properties' in Paint and resize by using a percentage.

[Beans&Tuba]

thanks Dan I'll give that a try

[TubaTed]

I really appreciate the help and effort!

Friends don't let friends play out of tune, right?

Cheers!
Ted

[TubaTed]

Bloke & Dan,

Will two second valve tuning slide crooks and a couple of ferrules work? With a skilled tech of course.

Ted

[Dan Schultz]

Bloke & Dan,

Will two second valve tuning slide crooks and a couple of ferrules work? With a skilled tech of course.

Ted

That should work. In fact... those short 2nd slide crooks will minimize the chance of the slide making the circuit go flat.

[Beans&Tuba]

there is a picture on this forum In the for sale section on page 5 towards the bottom of the page labeled "Miraphone 186 BB flat sale pending" by Liberty mo, this picture shows the return loop fourth valve slide.

[TubaTed]

I'm having a little difficulty finding ferrules for this project. Basically, tubing with .800+ I.D. Anyone?

[Dan Schultz]

I'm having a little difficulty finding ferrules for this project. Basically, tubing with .800+ I.D. Anyone?

Ed Stregge at Badger State should have everything you need for the slide.

Ed Stregge
Badger State Repair
204 W. Centralia St.
Elkhorn, WI 53121
Phone (262) 723-4062
Fax (262) 723-2587
mrstregs@aol.com" target="_blank