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Lee was commissioned to build a 6/4 CC using a Kanstul valve set and bell and the body of a mammoth Martin. The photos show the first installment of a work in progress. This horn has a .689 bore, a 20.75" bell constructed of heavy wall brass (0.040"). The overall height of the horn is about three inches longer than the CSO Yorks. Lee wasn't able to get this specific measurement before he shipped the horn this afternoon, but it's evident that it's a big horn. This is a one-off model but if you're interested in more details, contact Lee at tubameister1@juno.com" target="_blank" target="_blank" target="_blank" target="_blank" target="_blank. Enjoy!

Wow! Great engraving, too. Is the hope that Kanstul will eventually reverse-engineer the Martin body?

Plus, I love the idea of American-made tubas!

I wonder how intonation is. Usually horns with huge inner bows have 'issues'.

Also, the gigantic (and "seamless"!) bell looks very nice.

bort wrote:Also, the gigantic (and "seamless"!) bell looks very nice.

The seam is pretty prominent in the last picture.

Yes, and that's what most tubas have. I think seamless isn't the right word, just not sure what else to call it... I mean that the seam is hidden, or smooth, as opposed to other Kanstuls where it has the beading around exterior of the seam.

Nice looking horn. Knowing Lee's attention to detail and craftsmanship, I bet it will sound great, too.

More from Lee on intonation and response:

"The intonation and response is really very even, some notes are a little easier than others, but none are difficult. Ironically, the "Bydlo" excerpt is very easy to play on it, clear as a euphonium. The low register from C down to the low F is very strong, and the privileged tones from low F down to the pedals are so good that I would not add a 5th valve for my own use.'

The valve set is removable via four screws and the leadpipe by two.

How cool is THAT? Now if Lee was only 1,000 miles closer .....

Hey Lee, how close are you to an Amtrak station??? Maybe a train excursion is in order....

Man, those Martin bows are F-A-T
I like that Kanstul valve section & bell!

Yes, there it is, representing a LOT of work. Now you know why I've been on the web so little, and in the shop so much (!) I will try to remember and answer the questions and comments.

I now know why other tuba cutters (BBb to CC) do not do the 20-series Conns or the Martins. As Uncle Beer stated, most cut-tubas with large inner branches have issues with tuning and response, as almost inevitably something in the taper has been compromised to make the cut possible. In cutting a tuba from BBb to CC, it is advantageous to either substitute a larger-bore valveset, like I did on my first project, which allowed me to discard the first small branch of tubing after the valveset entirely, or use a shorter bell, as Mr. Gnagey has in his hugely-popular King CC conversions. To build a Martin-esque 6/4 CC for this customer, he wanted to use a Kanstul heavy-wall bell the same size as the CSO #2 bell, which was a perfect fit, but did not allow any shortening. He also wanted a .689" bore, which did not allow any shortening from that part of the taper. So, I had to do an enormous amount of work in measuring, measuring and re-measuring tubing, cutting, and modifying the ends of tubing branches until they fit and made sense that way. I cut up much of the branches of an old Cousenon tuba to use as reducing mandrels. To reduce the end of a branch, I heated it to red-hot, then shoved it into the reducing mandrel and worked it until it was the right size, sometimes taking several tries. No tubing is "telescoped" at all in the taper, but I did have to remove the 5th valve after the valveset because it was not large-enough, soon-enough.

The good news is that the tuba plays rather evenly through nearly 5 octaves with no stinker notes. The Eb just below the staff did not immediately feel exactly as good as some other notes, but it slots, is in-tune, and when I listened to someone else play it, I think it is more of a player perception than anything coming out the bell, as it sounded fine. Several notes were fixed by changes in the placement of braces. The standard-looking braces from the bell to 1st valve tubing and bottom bow to the main tuning slide are detachable, as I drilled and tapped the brace sockets at the valveset. Two screws there, two allen bolts on the other side, and a screw and a bolt on the leadpipe allow the valveset and leadpipe to be removed in about one minute.

The sound of the instrument is it's own, decidedly like a Martin, but with the York bell it has more of a defined edge to the sound, sort of like a slightly larger Conn Grand Orchestral in CC. I like the Kanstul-York receiver, which accomodates both American-shank mouthpieces and the slightly larger European-shank mouthpieces. Because of it being such a large, conical tub of a horn, the privileged tones are actual usable notes that have no stuffiness or resistance, and are pretty clear and in-tune. The high range is stable and clear, partly I think because of the smaller-bore valveset. After the owner, who is a scientist, does electronic testing of the instrument and we have it finished, we plan to silver-plate it, and we'll post more photos.

And yes, there is talk of Kanstul building a 6/4 CC in the future. As far as reverse-engineering the old Martin Mammoth, Mr. Kanstul did that years ago with the 900/4B BBb. It did not look like a Martin, but the tapers were right and it played like a Martin Mammoth, or slightly better.