When using a simple keyboard, the slave or second keyboard will only play the tone that is set on the host or primary keyboard. However, if you have a keyboard that has a mixer, it is possible to have one tone sound if the slave is played, and create a second tone that sounds on a different channel.
This would be useful if you want to play a DIgital Piano, which has very high quality Grand Piano tones, but like the rhythms and saxophone tones on a WK unit. You can play the Digital Piano and each time you press a key it would send a signal to the WK to play a guitar sound at the same time.
Following is an example of ho this would work between a PX400 as the host, and a WK1630 as the slave. Other models may be slightly different, but the principle is the same.
What we are going to look at is page 30 in the WK1630 manual, and page 27 in the PX400 manual.
First, on the PX400 you are going to see what channel the keyboard is sending on.
1) Press Setting
2) Use the Left and right arrow to get to Keyboard channel.
3) You can use the wheel to change the channel
4) Press Setting
On the WK1630 we are going to change the parameters of the Channels
1) Press the Mixer Select Button until the Display shows External
2) Press Enter, a channel should flash
3) Use the right arrow to select the MIDI Channel from the PX400 It should flash on the bottom of the LCD
4) Enter the tone you want
5) Press Enter
Now it should sound like one tone on the PX400 and another should sound on the keyboard.