Blog Pages


Vacuum Tube D.I. Prototype

Finally found the time to build up the vacuum tube direct box. It is a tight fit but it all fits. I didn't have the actual parts in stock at the time of the build so I used what I had on hand. I will build up a second proto unit with the actual parts soon.

So far I have been powering it with my adjustable bench supply. I will be sourcing a stand-along supply soon. Features are minimal with a single input, a high-z output and a D.I. output. The two knobs are the level controls for each of the vacuum tube gain stages. Depending upon how you set the controls determines if the sound is clean or mean. It can really dirty things up.

An inside view shows the prototype mess. A Jensen transformer sits on the right side. The 12U7 dual triode sits in the middle horizontally. The final version will move things around a bit to make a little more space for the PCB assembly. The pots will most likely be reduced in size on the next rev.