Neil Bliss wrote:Hey folks,
My wife and I are discussing adding a room onto our home, and in the process I'm thinking that it would be a neat idea to make the dimensions "optimal" for practicing. Practically speaking, I'm working towards getting a nice resonance for the low range of the horn (low C, low Bb) out of the room. I know we've had some pretty good technical discussions lately on the waveform characteristics of F tuba low ranges, but has anyone here done any practical implementations of how to design the "perfect tuba room"?
Before anyone mentions it, no I can't get her to let me build a Cathedral as an addition.

The ideal shape is bigger than you would be willing to build onto a house. So any possibility is a compromise. But if you can build a room such that you could stretch a 32' rope out in several directions without it going slack, then you'll hear most of what there is down to the pedal register.
A taller ceiling does much more good than a bigger floor. My current practice room (the living room of my house) is the best I've ever had, and it has a sloped ceiling that rises from 8 feet on one side to 18 feet on the other side, where it opens into a loft on the second floor that opens out into the living room. From there, the ceiling continues up another four feet to a peak 22 feet above the living-room floor. Then, it slopes down to the far wall of the loft, which is about 12 feet back from where it opens out above the living room. That gives me a maximum dimension of about 25 feet, but there are diagonals that will accommodate that 32-foot rope and keep it taut.
In the other direction, the room is 24 feet long, and the loft somewhat less.
An important feature of that design is the sloping ceiling. The sound doesn't bounce right back down on me, and I get to hear it in the room a bit. The room also has few parallel surfaces and lots of things in the room to break up echo.
So, I would say make it as big as you can, with a high, sloping ceiling and minimize parallel walls.
Rick "enjoying the current arrangement except when the wife wants to watch TV in the adjacent room" Denney