The Midi commands for the MultiStomp are well know/documented, it seem that the G1Four has some slightly different commands for selecting effects and enabling/disabling them. ToneLib presumably already knows these, as claims to supports the pedals. Just documenting them for the DIY'ers.... Code: Turn on/off effect slots amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 00 00 01 00 00 00 00 F7' - slot 1, on amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 01 00 01 00 00 00 00 F7' - slot 2, on amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 01 00 00 00 00 00 00 F7' - slot 2, off etc.. Bypass Slot 2 amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 01 01 00 00 00 00 00 F7' load "rack comp" to slot 1 amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 00 01 20 00 00 08 00 F7' load "slow attack" to slot 1 amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 00 01 30 00 00 08 00 F7' ^^ ^^ ^^- Group??? should be group 1 << 3bits!! || ++- Effect (ID from FLST_SEQ) ++- Slot load "rack comp" to slot 2 amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 01 01 20 00 00 08 00 F7' EP_STOMP.ZD2 (ver= 1.30 ), group= 3 , id= 32 , installed= 1 load "EP Stamp" to slot 2 amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 01 01 20 00 00 18 00 F7' EP_STOMP.ZD2 (ver= 1.30 ), group= 3 , id= 32 , installed= 1 load "MS2x14" to slot 2 amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 01 01 10 00 00 28 00 F7' MS4X12.ZD2 (ver= 1.20 ), group= 5 , id= 16 , installed= 1 load "Bomber" to slot 2 amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 01 01 10 00 00 38 00 F7' BOMBER.ZD2 (ver= 1.30 ), group= 7 , id= 16 , installed= 1 load "blackOpt" to slot 2 amidi -p hw:1,0,0 -S 'F0 52 00 6E 64 03 00 01 01 10 00 00 0C 00 F7' BLACKOPT.ZD2 (ver= 1.20 ), group= 1 , id= 16 , installed= 0, unknown=1