TubeNet

Six valves on a tuba? Piece of cake. Check out this trumpet with lots of keys, a keyed bugle in effect. Haydn's trumpet player reportedly used a keyed bugle in the first performance of the new Concerto in Eb. The instrument depicted must have been a nightmare to produce.
https://youtu.be/WzHR46yaveQ?t=36" target="_blank

Ace

And a nightmare to play.
And listen to.
And...

Just wait until the serpent makes a comeback...

Pretty amazing sound for a horn with holes in it.

IsaacTuba wrote:Just wait until the serpent makes a comeback...

...like the ophicleide?

https://www.youtube.com/watch?v=GG5pbPcXnC0

The ophicleide is making one!!! It's slow, but now more of us are learning it

Sounds fine to me, but I’m guessing that the tempo may be faster than it was originally played.

Just a funny-shaped saxophone with a cornet mouthpiece.

I've played ophicleide in symphonic settings.
They actually make things easier to play, not harder.
Trust me: if a sax player can handle more keys, you can handle a few!

Though part of the saxophone's facility with keys comes from its ability to produce an effective tone corresponding to the 1st partial, and the easy key stuff is in the two octaves corresponding to 1st and 2nd partials. Which I guess would be be a valve nightmare. My very casual impression is that this trumpet thing is running more in the typical brass range in that respect, as by most accounts the ophicleide does as well. Which is not to say keys are not a valid way to design such an instrument, but not exactly analogous to the woodwinds (and I wonder if that could be done, i.e. keyed brass with a larger bore that can function effectively in its pedal range.)