Importing sound samples

After numerous failed attempts I deceided to make a thread about. I can extract samples from ROM and SPC files with either open SPC, snessor or SPC Tool but when comes the time to importing them in a FF3us ROM, I fail miserably.

First I'm trying to edit the sample with a tracker like openMPT or Madtracker 2. It simply doesn't import the sample and sometims I even get an error about the .wav signature.. I want my sample to have the same length as the one I'm replacing because there is 0 free bytes with FF3usME.

So is there a program to edit samples that would in a perfect world have a feature to set the size of the sample in blocks like in FF3usME. I have cubase but haven't really checked all its features and I'm a cubase noob except for midi.

Or even better...Is there a way to replace manually a sound? I mean I can open a WAV sample with a hex editor but can I copy/paste directly that data into the ROM and have a nice sample in the game? That would be the best...

Edit: Well after reading a bit more about the SPC-700, I finally managed to convert a wav sample extracted from a SPC file into a BRR sample using snesBrr. I was then able to fit it in the ROM.

I would like to expand the instrument bank of FF3us which would mean move data and pointers and change a couple of instruments to give a different feel to FFVI music. Another thing I want to do is replace sound effects but that would require some better understanding of Bank C5 and of the SPC-700 because sound samples are produce and shaped by the SPC core, I'm afraid the samples are not stored in their full length on after the others like brr samples.

We could use this thread to post about the best BRR samples we know to replace some samples of FFVI or anything related to snes sound/instruments samples.