Jason is right. I too have the peavey 6505+ 112 modified into a head, running through a valveking 4x12. A tube screamer or overdrive pedal will make your amp sound better. I currently use the new maxon st9 pro, which is based on the old ibanez ts808.
My ltd came with the 81/60 combo But after playing an ibanez with dimarzios I scored on CL I was blown away by the tone I got.
If you don't use an overdrive pedal I suggest you to try one with your 6505+.