Engl tube preamp in a single rack mount space. Has 4 channels kind of but really channel 1 switches between a clean and crunch setting and channel 2 switches between gain and more gain. Really has a large range of rock tones.
Since it is 1 rack space and tube it has the tubes lay horizontal in the chassis. They have a foam pad underneath them to pad them from vibration and also to isolate them from the PCB. In this case the foamy pad made the 12AX7 squeeze into the tube socket at an angle and it wore out the tube socket pins, making them become loose and untensioned. Because of this the signal would cut out occasionally and if you tapped on the chassis you could usually get the 12AX7 to make connection with the socket and it would cut back in. Re-tensioning the tube socket worked well but I wonder if one day it will eventually need to be replaced.