soz I don't think I was clear, as 'synthesiser' can be too ambiguous, so I'll try to show you what I am looking for.
A synthesiser for a midi program, that sounds better than your default one with windows, which with Final Fantasy VII you get a yamaha one, but I couldn't find it, and well I don't own FF7 anymore.
Here is a screeny of my track settings in Anvil Studio
As you can see under synthesiser it says 'general midi' and I am looking for a better one than that.
Unfortunately all I can find is studio hardware synthesizers and VST trackers