Output mixer for Eurorack

Inspired by the mixer in the Erica Synths x mki.edu line (but with added channels and SMD components)

Features

• Eurorack format (3U panel height = 133.4mm)
• 8HP width (about 40mm)
• 4 inputs with pan (L-R) and level adjustable
• 2 outputs, line out and headphone out
• Mostly SMD with a couple through hole parts

Issues

• Pan is reversed
• Not enough space for 1W 47R resistor
• BD139/140 overheating

All addressed in current version (v1.1). The overheating was a result of poor quality BD139 and BD140 that I had sourced.