TromboneChat

There's a discussion on Tubenet about an 8 position trombone, and someone posted a photo that seems to show an 8 position Courtois alto.

That seems useful to me. 8 positions on a tenor wouldn't be a bad idea but nobody has arms long enough. On an alto it might make sense. But that alto in the illustration has a rather tenor like shape.

Is an 8 position alto a thing? I've seen discussions here about altos not having even a true 7th for some models.

Some quick math, a Bb slide needs a bit over 23" of extension for 7 positions (plus bearing length, hand grip, etc).

An 8 position Eb slide would need almost 21" of extension. An Eb horn is also almost 28" shorter than a Bb horn.

So, for that, you could only cut 4" out of the slide, but you would need to cut a bit over 23"(!!!) out of a Bb bell section to get up to Eb. (not suggesting cutting a horn here, just using it as a visual reference).

With the trapped length in slide width, hand grip area, and main tuning width, it is hard to find enough length for taper in the bell section to get a proper 7 position slide, let alone 8. My home-built Eb horn only has a 5 position slide. It could be considered 6, but that 6th is barely hanging on.

Cheers,
Andy

I can't find the topic. Link?

There is a historical design with 8+ positions, but it involves a double slide.

Oh man, that alto would be ALL slide. It would look like a giant Soprano trombone.

I want one.

I just want an alto where the Brahms 2 "low" E doesn't involve an 80% chance of skewering the last-chair viola with the outer slide you just threw like a javelin.

Question.
If you take an F alto bell section and build a custom slide section with a length, so that this combination has an Eb in first position. does this result gives an Eb alto with 8 positionen? Cause bell section is shorter,
slide is longer.

heinzgries wrote: ↑Thu May 14, 2020 3:51 am Question.
If you take an F alto bell section and build a custom slide section with a length, so that this combination has an Eb in first position. does this result gives an Eb alto with 8 positionen? Cause bell section is shorter,
slide is longer.

Maybe? An F alto is almost 9" shorter than an Eb Alto. The slide would probably have normally have required 4" total length less, so you get 5" out of the bell without too much difficulty. The difference between 7 and 8 positions on the alto slide would be ~2.5" of extension, so it could be close. It would be a ton of slide and very little room for taper in the bell section.

Not sure if I have seen an F alto that was worth playing, however.

Cheers,
Andy

Here's link.

http://forums.chisham.com/viewtopic.php?f=2&t=96519

I've forgotten how to insert an image but within that thread is a photo from a Courtois catalog that supposedly shows a tenor shaped alto.

Trill valve in 7th?

timothy42b wrote: ↑Thu May 14, 2020 5:55 am Here's link.

http://forums.chisham.com/viewtopic.php?f=2&t=96519

I've forgotten how to insert an image but within that thread is a photo from a Courtois catalog that supposedly shows a tenor shaped alto.

WHOA. That can't be to scale. It's almost as long as the Tenor, and it definitely says it's in "mi b".

I combined an F alto bell section with a Bb slide section. This resulted a trombone in high Db.
For a pitch in Eb the slide must be nearly 5" shorter.

Hum. Just some clarification, the picture doesn't say the pictured instruments have 8 positions. It shows the main instruments in their line-up, namely normal alto, tenor, tenor-bass and contrabass. And then mentions "other creations and models exclusive to our company" (i.e. novelty instruments): piccolo trombone, soprano trombone and 8-position tenor trombone.

The 8 positions thing applies only to the tenor they are mentioning (and which isn't pictured on the page). There is no mention of an 8 position alto there.

Keep in mind, old French small bore instruments such as these had much less taper in the bell section, typically not until the tuning slide, and sometimes not until the bell itself; in any case cylindrical neckpipes. That and they have very narrow slides and narrow bell sections (bells are usually under 7" in diameter). So you have much more margin on these instruments to take length out of the bell section and redistribute it to the slide without changing the conicity of the instrument.

I'll add that the folks on Tubenet are wrong, there are absolutely reasons why it's hard to have 7, let alone 8 or 9 positions on an alto, and particularly a modern alto with more conical tubing. There are sections on a trombone that can't be made proportionally shorter (i.e. the bows), so the shorter the overall instrument, the smaller the margin to move tubing to the slide section is, relative to the overall length. That was already a problem in trying to make 7-position alto slides early on, and is only made worse by the fact that modern altos have more conical length than earlier altos had.

Weird I replied but it disappeared.

But that does make sense.

I did an experiment yesterday. I put my tenor pBone slide on my alto pBone bell n

It played as a very sharp C or very flat Db.

timothy42b wrote: ↑Sun May 17, 2020 9:53 am Weird I replied but it disappeared.

But that does make sense.

I did an experiment yesterday. I put my tenor pBone slide on my alto pBone bell n

It played as a very sharp C or very flat Db.

with a F alto bell it makes a high Db

paulyg wrote: ↑Thu May 14, 2020 12:54 am I just want an alto where the Brahms 2 "low" E doesn't involve an 80% chance of skewering the last-chair viola with the outer slide you just threw like a javelin.

I built one. It was a new old-stock Larry Minick bell never installed on a horn. I built an extra long nickel silver slide and German style red brass J crook tuning slide. You can play E in tune with about 3 inches left on the slide. It actually will go all the way to a very sharp Eb.

nice horn, looks great