Gio writes in to tell us about his latest vacuum tube-based audio amplifier design, the 5751 SRPP / EL84 (6BQ5) Push-Pull Tube Amp. If you’ve been itching to try your hand at building such a thing, this looks like it could be a good place to start. The circuit has been designed to have high enough gain to connect directly to an MP3 player, and they are using simpler parts to keep the cost of the project down.
Curious about what all those things in the name mean? Well, 5751 and EL84 are the model numbers for the vacuum tubes used in the project, and push-pull refers to the type of audio amplifier circuit that the project is based around.
Circuit schematics are included, however you need to be careful when working with this and any other vacuum tube projects, as the high voltage required to run them can be deadly.