Compensating B-flat tubas

[P@rick]

What I was trying to say is that the horn makes the correct PROPORTIONAL addition for valves 1,2,3 when used with the 4th valve.

That is what I meant by double horn.

Right

[P@rick]

...certainly more restrictive with a lot of valves down and must be blown differently. The gain is good intonation with really easy fingerings which is a godsend in modern Bb Bass brass band writing.

This is my experience too. I blow differently depending on the valve combination used. I got used to it and the audience certainly doesn’t hear or notice this. I prefer blowing a non-comp but having only 4 valves on a comp instead of 5 on a non-comp is also an advantage (especially for amateur players).

I guess this is also a reason why you see so many compensating tubas in Dutch amateur HaFaBra (Harmony, Fanfare and Brassband).

What I didn’t get used to is the 3+1 layout of the valves in the short time I played it. I played a Besson with a 3+1 valve layout and I didn’t get used to using the left hand for the 4th valve (but I guess this just takes time). I don’t think I would ever like (or get used to) the playing position on a 3+1 valve layout. The way you left arm is wrapped around the tuba to reach the 4th and how your upper body is twisted annoyed me.

This is why I’m very happy with my Besson 993 (4 valve front action comp)!

[imperialbari]

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 1369961097

[SousaWarrior9]

Remember too, that there are two very separate KINDS of compensation-
a 3 valve compensating horn makes up for the length distance when using valves in combination, a 3+1 is essentially a compensating DOUBLE horn which does not compensate for valve combinations, only making the horn uniformly longer when the 4th valve is used.

The 3+1 is not making the horn uniformly longer when using the 4th valve. It depends on which valve combination you use.

Quite.
A 4v comp ignores the issues with valves 1-3 used in combo. Rather it addresses the more considerable shortfall in tubing only when using 4th PLUS any other valve(s).

Having spent considerable time on both comp & non, a comper is certainly more restrictive with a lot of valves down and must be blown differently. The gain is good intonation with really easy fingerings which is a godsend in modern Bb Bass brass band writing.

Wait, hang on, I need some clarification. I was under the assumption that the 4th valve on a 3+1 compensating tuba would, when depressed, lower each valve and the open bugle by proportional amounts. Like for example, pressing the 4th valve on an Eb comp would essentially turn it in to a 3-valve BBb tuba. Of course, having had no experience with compensating instruments, this was really just an uneducated assumption. The first comment quoted seems to back up my assumption, but others are disagreeing. In short, what I'm asking is: does a 4-valve compensating system make a horn uniformly longer, i.e. able to be played in 2 different keys (although I know that's not the system's intended use) or does it simply add small enough lengths of tubing to each valve to correct intonation, without completely changing the key?

[Donn]

but others are disagreeing.

I disagree - no one has disagreed.

[SousaWarrior9]

I disagree - no one has disagreed.

Ok, I was misinterpreting what was being said, which is why I asked for clarification.
First, I saw windshieldbug's comment saying 4v compensating horns make "the horn uniformly longer when the 4th valve is used", then I say P@rick's comment saying that it "doesn't make the horn uniformly longer" I perceived that to be conflicting statements which is why I was confused.

Basically, I just want to know if a 4v compensating horn is completely changed into a different key when using the 4th valve or not. Because I've never played one, nor have access to one, I can't find out for myself so I figured asking the board would be my best bet.

[Donn]

I am not crazy about the "completely different key" notion, but I guess it's as apt as "double horn."

Maybe what's throwing you off is that "uniformly longer" sounds like we might be talking about some kind of major engineering feat. It isn't, it's just what happens with any common tuba when a valve is opened. The total length is now somewhat longer thanks to the valve, and it's that much longer irrespective of what other valves may be open at the moment. Uniformly longer. Unless compensating plumbing makes it NOT uniformly longer. Windshieldbug did say that wrong, but then recognized his mistake shortly afterwards; I imagine he may have been thinking uniformly lower pitch and then decided to change terms to length, but neglected to compensate for the change.

[Ulli]

...or does it simply add small enough lengths of tubing to each valve to correct intonation, without completely changing the key?

That's it.

[Peach]

...or does it simply add small enough lengths of tubing to each valve to correct intonation, without completely changing the key?

That's it.

Ulli, I should probably leave it there, however...

Sousa was right suggesting that a 4v comp is a compensating double. Our trombone buddies will say they have a Bb/F trombone with the valve putting the trombone into F, so the positions have to be longer to compensate.
A 4v Comp Bb tuba is a Bb/F compensating double.

The difference between a 3 & 4v comp is when the compensating kicks in.
A 3v compensates using 3rd valve combinations: 1+3, 2+3, & 1+2+3.
A 4v misses out on the 2+3 deficiencies since it only compensates combinations involving the 4th valve.

More confused or less?

[imperialbari]

Euphonium players have been seen using the 4th valve and no other valves for extremely fast playing in Bb major in the range above A on top of the staff (bass clef).

Klaus