If i am using unbalanced cables in the 'A Balanced output', then connected to my Yamaha amp, is that going to effect the sound?
I can't use balanced because my amp is not balanced.
Thnakyou!

I don't think there will be a problem if you have TS connectors on each end. If one was TRS, you would have a loss of headroom. Either way, the biggest problem is you won't have any noise rejection that balanced connections offer.

Yea, noise rejection is the main advantage of using balanced cable connections. I have never had a problem in a home set-up and from what I have read, if your cable runs are less than 20 ft. single ended should be fine. I suppose it depends to some extent on the noise sources around you.

Using unbalanced cables/plugs on a 'balanced' circuit will reduce your signal by upto 50% (here is a bad analogy, but it gets the point across: 'its almost like using a bicycle with only one leg'). I've tested the use of balanced vs unbalanced cables( 1/4"TRS/stereo vs. 1/4"TS/mono) on each the left and right outputs of my FantomX6 to my bi-amped studio monitors. Its clearly louder and crisper using the 'balanced' cable (1/4"TRS/stereo). BIG DIFFERENCE ! I also suggest you always check your manuals for your eq' to decide on all your hook-ups, its worth spending the extra ~$50 on correct cables, because this will ensure your equipment is impedance(circuit talk) matched for quality sound and long life.

But what if you are going from a Fantom directly to a Roland KC-350 amp that only as TS input jacks?

@razyrocket - you are correct, you are basically loosing half of the signal by not connecting the cold half of the balanced circuit.

I think I was making an assertion this won't be a huge issue for OP, if he is using an amp. to play through at home. Obviously, this would be less than recommended for recording or live performance(albeit in both cases it could be assumed XLR inputs would be available).

Guys, I have a question.

when you have the balanced option on the mixer, you can use It with TRS right? But, just wondering If I can make a trs/xlr cable to use It when I don´t have the TRS option at the mixer (only TR). And the phantom power on (at the mixer) can damage my fantom on this case?

Thanks

It will not harm anything, but You could get noise and earth-loop if You not connect everything correctly (hot,cold, 1-2-3)
I used to made such a cable for my Simmons SDS-V, which has XLR and my mixer had jack ins only.
Just look after the spec of the XLR wiring of Your equipment first (maybe its a MIC compatible system)
on the SDS-V it was totally different ('81 model)

Thanks Nord! Nice nickname btw. :)