Position the MPC 1000 and the MIDI keyboard so that they are accessible to you and to each other.
Locate the MIDI ports on each device.
Insert one end of a MIDI cable into the "MIDI IN 1" port on the MPC 1000 and the other end to the "MIDI OUT" port on the keyboard.
Insert the second MIDI cable into the "MIDI OUT A" port on the MPC 1000 and the "MIDI IN" port on the keyboard.
Use the MPC 1000 to set the keyboard to "Local Off."
Select the "MIDI/SYNC" mode and on the "MIDI" tab, set the "Active Track Receive Channel" to "All" and the "Soft Thru" to "As Track." Once you've done this, your MPC 1000 and MIDI keyboard should be able to play the same sounds.