Your speakers are 4ohm speakers, correct?
Okay - - - - - - - - - - - - - if you have 4 ohm speakers, you are GOING TO HAVE TO Run your amplifier at 4ohms. There is no way to make a 4ohm speaker run an amplifier at 2ohms.
4ohm speaker means it's going to be 4ohms on the amplifier.
You are going to be powering your speakers with 50x4, seing that they are all single voice coil 4ohm speakers.
And you'll be fine - - - just please dont jack the gains and be stupid with them trying to get them louder. Check out the tutorials on this site to tune their amplifier in a bit better.