jacobg wrote:I realize that the toilet seat tuba might seem well balanced, but ponder for a second:
If someone asked you to carry a weight of 15-40 lbs, in any form, for 3 hours, what would be the best way to do it?
Isn't this exactly what outdoor backpackers have to do? And don't they choose to carry the backpack with two shoulder straps, loosely attached to their backs, with a frame that touches their butts, and a strap around their waist?
I'm using armchair ergonomics here, but it seems as if the butt acts as a third point to distribute the weight, and your upper back (rhomboid and deltoid) makes for a stronger base than the trapezius muscles adjacent to the neck.
This discussion actually starts my thoughts down the path of building a backpack-like frame and straps then modifying a helicon/sousaphone design so that the entire instrument hangs off of that frame with the COG at waist height.
Adjustable straps are necessary so that the bell will fit above the player's head regardless of height (or so that the instrument body isn't below the player's hips for marching. With adjustment to the straps, a piano bench should be comfortable (no back interfering with the tuba).
Start with a Helicon with a lengthened mouthpipe. Rotate the valveset as needed for ergonomics.
Two options for the bell:
1 - Stay Helicon. Bell under the left arm, pointing forward. Not ideal for sitting in a chair in a group rehearsal, but should work fine on a marching field (as long as the bass drums aren't incorrectly placed).
2 - Modified Sousaphone/Recording Tuba. This time the bell needs a taller section between the gooseneck at the top and the right angle at the body. Make it tall enough to place the bell over the player's head (centered). This one's also tricky because of the length of pipe going up the player's back.
The design for bell option 2 may end up looking more like a twisted open paperclip with the final wrap going around 1 side to the bell behind the player before heading up. It also allows the player to put the instrument on from 1 side (clipping into the frame) instead of having to lift the entire thing over their head.