The door on the top panel of every Backert Labs preamp gives you easy access to your tubes.
Two 12au7’s are beneath it, and you don’t need a screwdriver or anything else to get at them.
Removing the tube door on any Backert Labs preamp is so easy a child can do it. Which is why under the tube door, we surround the tubes with a protective enclosure that protects little fingers from reaching past the tubes to the circuit board.
Tube door on the Rhythm preamp. Always turn off power amplifiers and Rhythm 1.1 before removing tubes.
Close-up of the tube door on a Rhythm 1.1 in anodized grey aluminum.