MTS Pre or Post Valve Section???

[groovlow]

Why has the pre valve section, main tuning slide [MTS] gone out of style or usage?
Hirsbrunner[?] and Yamaha student horns were the last I recall.
Is it too cylindrical too early in the cone? Is it cheaper to build post?
What are the playability or tonal issues? Possible tradeoffs?
Joe H

[windshieldbug]

The change in the bore profile affects the tone.
And the use of a main tuning slide in the mouthpipe limits where the valves can occur in that profile.
Valve tubing is cylindrical.

As brass have moved to larger bores and warmer sounds, tubas have followed along.
Just like trumpets have become more cornet-like.

[bloke]

Mouthpipes should be long - as with notary tubas. but - if they're piston tubas - they need to have a tuning slide going up (where the number one slide normally is) before the valve block.
Were tubas built like that, we could get by with three valves - or certainly with only four.

[UncleBeer]

For what it's worth, Ren Schilke was of the opinion that one of the most important factors of the success or failure of a valved brass instrument was where the valve set was placed along the length of the windway. He also felt that the stretch of windway from receiver to valve set was critical to centering and intonation, and that's why his trumpets often had the bell-tuning feature.

[groovlow]

@UncleBeer does the computer software you use to analyze instruments, give any indication of an ideal place for the valve section? Thanks for the Schilke "centering & pitch".
Location, location,, Location?
Joe H

[UncleBeer]

@UncleBeer does the computer software you use to analyze instruments, give any indication of an ideal place for the valve section?

There's a "physical modeling" component where you can create a hypothetical instrument based on internal bore diameter at hundreds (thousands on a tuba!) points along the length of the instrument, and get a pretty good idea of what that instrument's characteristics might be. It's pretty complex and labor-intensive (designating all those diameters) so I've only goofed around with it so far. Someday...

More info: https://www.artim.at/en/optimizer_information/

... and even MORE info: https://www.artim.at/en/optimizer_features/

[bloke]

@Unclebeer

Due to pretests hinting at good results (along with laughably low monetary cost), I brought a 40-year-old Yamaha bass trombone bell section completely back from the dead and altered it to receive a 60-year-old duo-bore slide-tuning bass trombone playing slide made by Olds.

(This instrument will eventually become a 6-valve B-flat bass trombone cimbasso, but I also wanted it to have a playing slide.)

I have discovered that monkeying around between tuning the bell section tuning slide and the playing slide tuning slide slightly alters the tuning characteristics (but - really - not very much).

[Sousaswag]

Hirsbrunner’s 2P is a pretty neat example of how one can transfer a piston section onto a rotary body.

The one I owned was a good player. Some love, some hate, but there’s one horn that the odd design works with.

The older tubas made here (USA) with the loops in the leadpipe seem to me to suffer from poor design due to lack of knowledge? Maybe that’s the story with the HB too, but many folks love ‘em.

Ultimately though, the “correct” looking stuff generally isn’t as quirky with pitch or response. My HB was (IS) nice, but it was no M-W 5450 in terms of low range response.

It’s been a L-O-N-G time since I’ve played the HB-21, but I would love to play one side by side to the 2P to see if the changes they made to that horn were worth anything. If just comparing low range response/ease, I’d guess the 21 would win, but in terms of pitch, that edge goes to the 2P.

[UncleBeer]

Hirsbrunner’s 2P is a pretty neat example of how one can transfer a piston section onto a rotary body.

I had one of those for awhile. Was never very happy with it, so eventually scavenged it for parts, finding lots of build mistakes as I did. Maybe it was a "Monday horn".

Tsk, tsk, Hirsbrunner.

[bloke]

I've posted this too many times, but - with the 2P thing - they missed an obvious opportunity to make lemonade out of a lemon.
As quirky as the tuning is with those things (and some people say "response", but I say "working really hard to play out-of-tune pitches in-tune") that funny little tuning slide (again) could have been stuck where the #1 slide is normally situated so that (unlike Marzan) it COULD have been a PRACTICAL tune-any-note tuba.