Wayne Parham Messages: 18789 Registered: January 2001
Illuminati (33rd Degree)
That's right, it's 1-7/8" long.
I'm pretty sure your cardboard tube is the same thing we put in the kits (and in our finished loudspeakers). It's available as a mailer tube, also sometimes used to store architectural drawings and blueprints. It's very rigid - I've joked you can use this stuff for baseball bats and am only half kidding.