I wanted to isolate the left and right outputs from my SP-TFB-2 mics, so a friend and I made a simple Y cable to split the signals into two isolated mono channels. With this cable, I'm able to maintain channel separation while recording into an I/O box. I believe this will be important because it gives me greater access to specific L or R signals without mixing everything into one waveform. The cable was made from the following for $18.70 from Home Hardware at College & Spadina (part number):
1 x 8' standard mic cable
1 x 1/4" stereo jack (K3545)
2 x 1/4" mono plug (K309421)
1 x 3.5mm - 1/4" stereo adapter (K309421)
heat shrink tubing
Haven't soldered since I was in high school, so I enjoyed it. Looking forward to possibly making some relevant parts for this project, such as an auxiliary power supply for field recording.