Is it possible to create a complete new performance, or just to overwrite an existing one?

The answer is yes to both. Here’s what that means.

The CP4 STAGE has individual instruments (Voices) that can occupy one of three “Parts” of a Performance. The MAIN Part, the LAYER Part, and the SPLIT Part.
It works as a main sound across all keys. This Main Part can be layered with a second sound across all keys. If you add the Split, then this Part will become the left hand, while the others will be the right hand.

The MAIN Part is always active
The LAYER Part is added to the Main Part
The SPLIT Part occupies the lower portion of the keyboard (Main/Layer become upper)

A Performance memorizes what Voice is in each Part and whether or not it is active when you first recall it.
There are 128 User Performances. They are all User... in a situation like this pre-setting them would assume Yamaha “knows’ where you want to split the keyboard and what combinations you desire/require... think of the factory Performances as being provided to show you exactly what types of things are possible... then, please make your own!

You are meant to study them, learn from them, and then create your own 128 User Performances. For those that need more complex setups than just piano, electric piano and the occasional split, the design concept is create your setups and store them in order 001~128. You can use an optional Foot Switch to advance through your configurations.

Page 21 of the Owner’s Manual gives a great visual of the two methods of using Performances considering how they deal with Voices assigned to the Parts.

A stored Performance, when changed, will recall three new Voices
You could simply work by changing the Voice occupying the MAIN Part.

It is worth the time getting clear on these two methods.

Performances can be stored and restored, as BULK DUMP data Out via MIDI, or you store your Performance setups to one of the 128 internal Performance locations... yes, by overwriting what is already programmed in that location. Again, all factory Performances are in User Memory and are to be overwritten.
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