We may need a little more information to be able to fully help, but I'll see what I can do here. First of all, please realize that what I will suggest is based on my knowledge of my keyboard, which is the PSR-E433, one of your keyboard's predecessors. While your keyboard (the E473) of course adds more sounds, styles, and effects, I do believe much of the main/dual/split voice and auto accompaniment functions and capabilities of both keyboards are similar (though I know you can revoice the styles of the E473, in other words, change the instruments that an auto accompaniment style is playing, which is not possible on my E433). Also, I know that the workflow, or the sequence of button-presses to achieve desired sounds and results, is quite a bit different on the newer E473 than on my E433, so I can only give you advice in general terms, and not in exactly what buttons to press on your keyboard.
So, first of all, you say you want to split the keyboard, but then you want to choose a voice for the whole keyboard. Unfortunately, that is not possible. Once you split the keyboard, it is almost like you are now dealing with two separate keyboards, and you cannot select one "global" voice that spans the entire keyboard. The closest that you can get is to select the same sound for the main voice and the split voice, and make sure the octaves of each line up so that notes will not jump or overlap when you go from the left part of the split keyboard to the right part of it. But this has limitations. First of all, you can add a dual voice to the right side part of the keyboard, but not the left side, so if you do use dual voice for the right side part of the keyboard, then you won't be able to get the left side to sound exactly the same as the right side. You might be able to come close with certain combinations -- for example, if you use piano and strings as your main and dual voices for the right side of the keyboard, then you can use the piano/strings voice of the XGLite section for the split side, but this voice may not be as good of quality as using individual piano and strings sounds for the main and dual voices of the right side. Also, certain sound-shaping functions, like the filter and envelope generator, are available on the main and dual voices, but not the split voice.
I briefly want to point out that there may be a piano/strings sound in the main "panel voices", and not just the XGLite voices, but if so, and if it is like my E433, then this really isn't a single sound -- it just automatically turns on dual voice, puts the piano in the main voice, and puts the strings in the dual voice. If you try to select this "panel voice" piano/strings sound as a split voice (the voice for the left side of the split keyboard), then since you cannot add a layered or dual voice on the left side, you will only get the piano sound, not the strings. There are several other panel voice selections that also automatically add a dual voice, and therefore won't sound the same when used as a split voice.
Next, you say you want to NOT use a style, yet you want to use ACMP, by which I assume you mean the auto accompaniment. This is kind of contradictory, as well, as the auto accompaniment is generally used with a style. So, when you say you want to use the ACMP, but not a style, do you mean that you just want to use the drums of the style, but not all of the other backing instruments? This is possible -- just keep ACMP off, but use the style start/stop/fill etc. buttons to start and control only the drums of whatever style is currently selected.
OR... Do you mean that you want no style accompaniment at all -- not even drums -- but you want to still be able to play the "easy play" chords with one, two, or three fingers? I wasn't sure about this, so I just checked to see what happens on my keyboard when I try this. With my keyboard, when I turn on ACMP to get the easy-play chords, but do NOT start a style, there are two possibilities:
1. If the split-keyboard function is not on, then the accompaniment part of the keyboard will just play a string sound with a bass note for whatever chord you're playing... or...
2. If the split-keyboard function IS turned on, then you will get the selected split voice, and the easy-play chords will use that split voice (this kind of surprised me), but it will still add a bass note. And yes, you can still change the split voice settings, like volume, octave, reverb, and chorus, and it will affect the sound of the easy-play chords using the split voice. So, if you do this, and use the instructions I provided above to try to match the split voice sound as much as possible to the sound you set up on the right side of the keyboard with your main and dual voices, then this is likely about as close as you can get to the same sound throughout the entire keyboard, while still being able to play easy-play chords on the left side of the keyboard, while having no style playing. However, each time you play a note or chord on the split or left side of the keyboard, it will strike a bass note, which can definitely affect the overall sound.
Now, there's one more possibility. Let's say you want the same sound throughout the entire keyboard, and you want the left side to play the easy-play chords to play that sound, and you also want the drums going in the background, but you do NOT want all of the other instrumental accompaniment of the style. You can just do "Number 2" above (turn on the split voice and the auto accompaniment, and select your main, dual, and split voices to try to have the left and right sides of the keyboard sounding similar), and then turn on the ACMP (auto accompaniment). Then, turn OFF all of the style parts, like bass and pads, EXCEPT the drums. This gets you the effect described in "Number 2" above, while adding drums, but no other style accompaniment. Curiously, when you do this, and the style is on (drums are playing), with the bass part of the style switched off, you do NOT get that bass note struck with each note or chord played on the left part of the keyboard. But if you stop the style and stop the drums from playing, then the bass note returns, whether you have the "bass" part of the style turned on or not.
I know this post is long and contains a lot of information, but I hope it helps. Please let us know if you have any more questions or want to provide some more clarification about what you're trying to do.
