Our problem was sending a balanced stereo mix coming through a pair of XLRs into an unbalanced 1/8” stereo mic input to an A-V mixer. I had thrown together a custom Y-adapter to hook everything up. There was hum, but it was tolerable and there were constant complaints about overloads even with the console turned way down. One evening the hum became an issue, and we had to make it go away. I realized we needed re-amplifiers. Everything was really expensive and we needed two, so I took a chance on L2A kits. I hadn’t put together a kit since a Heathkit oscilloscope in the 70s, and these instructions are fabulous! The components were first class: 1% resistors, military grade pc board, Neutrik combo inputs. I’ve taken a number of DI boxes apart, and there’s nothing in them like this. I tested the box using pink noise from the console and monitoring with third octave spectrum. I had to use a mic input to get a decent level, so one big problem solved! I flipped the hi-lo filter switch and saw one end of the spectrum collapse and then the other end collapse, so the L2A was ready to put into service (actually two of them). I put them in the signal path with the volume control at 12:00. No hum! I also was able to send a nice juicy signal from the console to the A-V mixer without overload. These things have really saved our bacon.