my guess is that unless you are running 100 feet or so of cabling, your problem isnt balanced v. unbalanced.
as someone said, hum and noise are two pretty different issues... perhaps you have both?
two different cures.
for hum you need to isolate the ground loop or just dont use your hum source, for noise you have to identify your noise source and possible upgrade/replace/avoid it.
i am in the middle of building a little hum isolation box myself to deal with the grounding issues of my effectron and spring reverb. pretty simple thing to build, mabye $20 job if you get the transformers from ebay.
the jensen transformer site has the schematic. before you get scared, the schematic consists of like 3 parts. anyone can build one. basically you just hook the audio up to the transformer, and put a little cap and a little resistor on the ground....
about as hard as makin cables.
as for noise issues, are you recording digital? for me, i have a bunch of things that i love the sound of, but are a bit noisy. i just record them and deal with all the noise gating at the computer. it is something that computers are great at... stripping silence, auto fades, noise gates (computers know the future).