Jean, the Sound Explorer button on the keyboard actually accesses all of the sounds on the keyboard and are thus shown in the Reference Guide under Sound Explorer Group. The other Sound Group buttons provide duplicate paths for quick access to various groups of sounds from the complete Sound Explorer Group. The MSB, LSB & PCNo columns are only of use if you are wishing to access the complete range of sounds from a sequencer program on a computer. If you want some individual help with MIDI problems or interpreting the Reference Guide don't hesitate to contact me directly.

Cheers

Len C.