Normalization is a method exclusively used on wave-spectra. It is not a method you can use on a collection of instruments, to make them lerp closer to each other. So nothing to do..?
In some way there is, because in a DAW you can use a compressor to make the 'louds' and the 'lows' get closer to each other. ( The actual maths behind can be found with Google : )
Otherwise you need to Normalize exported wave-file-stems, and then use them in LMMS as Sample-tracks
Besides that, since you are new in Forum
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