Ok, so I'm on the low end of drumming. I'm using an Alesis DM6 with a DrumRocker kit. The nemesis of my DM6 is my ION drum brain for Rockband PS3. ION uses 1/4in connectors on both ends while DM6 uses that Octopus cable with 1/4in on one end and DB-25 (Ye Olde Serial) connector on the other. This means having to switch cables every time you want to go from DM6 to Rockband and vice versa. A pain in the wazoo along with a mess of cables.
I got me one of these old A/B DB-25 switch boxes ($5 on ebay) and made my own Octo cable for the ION. Basically, I now have a straight DB25-DB25 cable between the DM6 and the switch box, the original DM6 octo cable from the switch box to the triggers, and my home made octo from the ION to the switchbox. That way, I can use the switch box to flip between DM6 and ION.
For those of you who might be interested in doing something similar, I mapped the pinout of the Alesis DB-25 Octo cable. Following pin layout in the image below, here is the mapping to the TRS (Tip, Ring, Sleeve) 1/4" connectors. Most are Tip/Ring only, but some (like the snare) are TRS.
1. Hi-Hat Controller Tip
2. Hi-Hat Controller Sleeve
3. Hi-Hat Tip
4. Open (No connection)
5. Crash Tip
6. Snare Sleeve
7 Snare Tip
8. Tom 1 Tip
9. Tom 2 Tip
10. Tom 3 Tip
11. Kick Tip
12. Open (No connection)
13. Ride Tip
14. Hi-Hat Controller Ring
15. Open (No connection)
16. Hi-Hat Ring
17. Crash Ring
18. Open (No connection)
19. Snare Ring
20. Open (No connection)
21. Tom 1 Ring
22. Tom 2 Ring
23. Tom 3 Ring
24. Kick Ring
25. Ride Ring
Hope this is useful to someone out there
- Ben