The B-17A is a prototype vacuum-tube bass preamplifier, pictured here. Details of the build process can be found in our blog (see Our Blog tab above).
Here is the circuit diagram – click on the diagram to enlarge it. Note that after initial testing C2 was removed for better frequency response.
The circuit was built using old-school turret board construction. Here is the board and the layout diagram. Note that the board in the picture is rotated 180 degrees from the layout diagram.
The power supply is located in the box on top of the main enclosure and looks like this:
Here is Parts List
Be sure to visit the blog and scroll back to earlier entries to review the story of the design and building of this preamp.