Bell Throat Circumference

[Dan Schultz]

You have to remember that where the bell ends is different on every horn out there. My Alexander has a very large bell throat, as measured at the end of the flare, but is not too large where it meets the bottom bow.

Huh! Isn't the poster talking about the circumference where the bell enters the ferrule at the bottom bow?

Even so... this information will be a little distorted by the fact that the bottom bows on European tubas tend to be a bit taller than those on American-style tubas. By European-style, I mean the Meinl and Mirafone rotaries. Included in the American-style tubas would be the Nirschle, Willson, and other piston horns. Hope I don't have to draw a picture. Hey, joe!... draw a picture for me. I ain't no good a 'MS paint'.

[windshieldbug]

This is a point that I hadn't considered. Still, I wonder if this information could be used to draw some sizing conclusions. What do you think? Is it totally usless?

Think about other instruments... soprano brass, for instance. What determines a trumpet vrs. a cornet vrs. a flugelhorn... and when? Today's trumpet bears more of a bore profile similarity to a cornet of 100 years ago than it does a trumpet!

A single point won't tell you that much, even if you COULD get a single reference point to work from. You need the entire bore profile, working from the valve bore to the bell flair to give you a proper comparison.

[Dan Schultz]

Dan, yes he is. But that is not in the same place on many tubas. My bell is one foot longer than on most BATs, which places the end at a much smaller part of the tube. If you measured the diameter of the bell from a fixed distance from the end you would get much more useful data since all of the measurements would be at the same point along the open tube, more of less. To just measure at the end of the bell as it enters the ferule is not too good since that point in most tubas happens at a different part of the open tube.

Well.... OK. I totally agree that there's no way to fix a size to specific makes of instruments due to construction differences.

A thread some eons ago suggest that a scale could be developed by calculating the volume of a horn. Perhaps a tuba could be weighed and then filled with water (all the tubing) and weighed again. By weight, one could reduce the numbers to cubic centimeters. Of course the instruments compared would have to be the same key.

[Dan Schultz]

I like this theory even better, but how am I going to fill it with water and weigh it? Sounds messy, and I bet it would make my wife just shake he head at me.

Well... you COULD just wait for warmer weather and do it outside. Use a garden hose and a bathroom scales. If you stand the tuba upright and attached the hose over the receiver you can begin filling the horn. When water breaches the top of the bell, operate the valves to fill the circuits. Hey! pour in a little Dawn and you can get your statistics AND clean your tuba at the same time!

(EDIT) oops! I forgot to add.... do this with all the tuning slides pushed 'in'... just for the sake of being consistant. If enough of you guys do this and send me the 'before' and 'after' weights of your horns, I'll put up a web page for comparisons. Fun?

[iiipopes]

Since some tubas are built with a short 1st so that you can push on the 5th partial, wouldn't you want to measure it with the slides set for everything in tune A=440 @ 72 degress F at the second or fourth partial after letting the horn acclimatize?

[tubatom91]

this is the stuff that should be catalouged and thrown into the "vaults" for future reference.

[Dan Schultz]

Since some tubas are built with a short 1st so that you can push on the 5th partial, wouldn't you want to measure it with the slides set for everything in tune A=440 @ 72 degress F at the second or fourth partial after letting the horn acclimatize?

Yea... let's throw in 'during a full moon', too!

One thing's for certain... you guys are finally going to find out where those leaks are!

I suppose we should also add 'don't try this alone'. In fact, all your tuba buddies could bring their horns and a case of Bud some Saturday afternoon... watch the game... have a few beers... and weigh your tubas!

PS... Sean, this isn't an attempt at lame humor. This could be the start of a new standard!

[Dan Schultz]

OK... If you're really going to do this... do it with all the slides removed except for just the main. That way, only the bugle will fill with water. if the valves leak, the water will simply run out of the open slides. (knew this was going to get complicated!).

[SplatterTone]

if the valves leak, the water will simply run out of the open slides.

Two or three bags of plaster should fix that little problem just fine.

[Wyvern]

Getting back to the original idea which I suggested. I realize the height of bells does vary, but measuring the circumference where the ferule joints the bottom bow does seem to give a good indication of size going by the fact that the 4/4 size 188 and PT-20 seem to be about the same at that point.

I am not saying it is the only measurement that shows the size, but is appears to be a useful one to gauge the potential size of tone of tubas, so would be interesting to know (as additional information to the published bell and bore size).

So, come on chaps, please borrow the tape measure from the wife's/mother's sowing box and measure the circumference (to the nearest inch) around the feral where the bell joins the bottom bow, and let us know


To start off, on tubas I have owned, or measured it is:

6/4 B&S Neptune = 19"
5/4 B&S PT-6 = 17"
4/4 B&S PT-20 = 15"
4/4 Miraphone 188 = 15"
Besson 981 Eb = 12"
Melton 2040/5 Eb = 12"

[Rick Denney]

PS... Sean, this isn't an attempt at lame humor. This could be the start of a new standard!

I seem to recall suggesting the volume approach some years ago.

I even offered to make the measurements, which isn't actually all that hard to do because most tubas are uniformly tapered for long sections of the bugle. All it would take is for the owners of relevant tubas to send them to me, and I'll take away the hassle of making the measurements. But I'm an exacting sort and it may take some time to get the measurements completed with sufficient precision.

About three years ought to do it. Less for horns that don't play well.

Rick "who can think of a couple of instruments that might defy accurate measurement indefinitely" Denney

[Bandmaster]

OK... If you're really going to do this... do it with all the slides removed except for just the main. That way, only the bugle will fill with water.

This makes total sense... otherwise how could you compare 3 valve, 4 valve and 5 valve tubas.

[windshieldbug]

This makes total sense... otherwise how could you compare 3 valve, 4 valve and 5 valve tubas.

Perhaps that's what the "/4" concept means after all: number of valves/4!

[Dan Schultz]

King 1235 (Eb) and 1240 (BBb) - 14 7/8"
Mirafone 186 BBb - 15 3/4"
Yamaha YBB 201 and 321 BBb - 14 1/2"
Getzen-Meinl 20 BBb - 14 3/8"
Conn 28J BBb - 15 1/2"
King 2341 Bbb (old style) - 14 7/8"
Bohland & Fuchs BBb - 17 1/8"
Marzan BBb (B & M) - 16 5/8"
DEG Caravelle (Willson) BBb - 11"

This is all the stuff I currently have in the stable. I'll provide more informaiton as it comes through the shop.

[SplatterTone]

Measuring around the ferrule (assuming you mean measure ON the ferrule)

Allora 186 BBb: 15 1/2"
Miraphone 191 BBb: 15 5/8"
Conn 14j Eb: 10 3/4"
No-name Chinese from Bandfolio about 3-4 years ago (which, by the way, is an excellent playing horn) BBb: 10 7/8"