ok now i know. so you have a preset, let's say a tone, that you made with your KPA. and you want to tone match that in the axe, and hopefully the result is that the axe tone match sounds the same as your KPA, yes?
i don't have a KPA. but i just looked at the manual and the KPA has direct outs meant to go to a mixer or similar in it's MASTER OUTPUT section. connect a 1/4" cable from the Master Out left and connect it to Input 2 left on your axe fx.
the axe fx is expecting a complete guitar tone, which means amp+cab sound. again i don't know how the KPA works specifically, so if you're just trying to tone match just the amp you profiled without a cabinet sim, it will not work well.
axefx to full range speaker:
start with a blank axe fx preset, add shunts from in to out. then add an amp block and a cab block. select an amp and cab that is similar to the tone you are trying to match. in other words if it's a distortion tone you want to match, don't use a clean amp/cab sound in the axe fx. you have to get close. again we are tone matching, not profiling here.
once that is done, add a ToneMatch block after the cab block. so it should be Shunts-Amp-Cab-ToneMatch-Shunts
go to the edit screen of the tonematch block. go to page 2, process. change REF SOURCE to INPUT 2, because we are using input 2 as the reference source.
go back to page 1 of the tonematch block. now it's time to produce sound from your KPA, since that is the reference tone. so you probably will have to plug your guitar into the KPA and play it to make sound. but not yet.
while ready to play your guitar as just mentioned, press the X button on the axefx front panel. then make the KPA make sound (play your guitar). the reference square on the left will fill up with data. after about 5-10 seconds, press the X button again to stop the reference capture process. don't worry too much about the brief moments when you are not playing guitar while you are pressing the X buttton.
now it's time to capture the local signal. plug your guitar into the normal input you use with the axe fx, like the front instrument input. now, press the Y button and play your guitar. the right square will fill up with data and after about 5-10 seconds press the Y button again to stop the capture process. it helps if you play the guitar the same way you played it when capturing X.
now press the Enter button on the axe front panel. this immediately completes the tone match process. the sound should have changed and your result is the tone match. going back to page 2 of the tonematch block, you have some options there, which are documented in the tone match manual.
if you are not using a full range speaker as the above example, and instead using a power amp and guitar cab as your speakers, just don't add a cab block in the axe preset, but everything else is the same.
i was explicit and added a lot of extra words in the explanation above, making it seem complicated, but really the steps are simply as follows:
plug in your guitar to the axefx
plug in your reference source to input 2
make a preset that sounds similar to the tone you want to match
add a tonematch block after the cab block (or after the amp if no cab block is used)
on page 2 of tonematch block, change REF SOURCE to Input 2
back to page 1 of tonematch block, press X and play your reference source. press X again to stop.
press Y and play your guitar. press Y again to stop.
press enter.
process complete.