engine loop making with ?

hallo
i hope you understand my english.
i have a problem
i have a wave file i make it with a wave editor and put it with
the sample editor 1.6 in the gp4 sound
but wen i play gp4 i here in the sound every second a plop
i mean this is the end of the wave file
what is the best way to make a engine file (loop ?)
what is the best wave editor for this
i have the wave editor from my soundblaster (and same from internet)
i load the engine wave file go on copy then i reverse the file and then copy
the normal file .then i have a loop ,but in gp4 i hear a plop
thanks for help

you basically need a good even rev sound sample to work from otherwise a lot of editing is needed, i used to use nero wave editor, load in the sample, select the best part of it, then make a copy and reverse it til it matches perfect, its just trial and error

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