Preamp no longer makes a difference after caps and wire

I just wanted to check if anyone else had this experience. My tube preamp use to be pretty important at removing the harshness from my dac. Since I’ve upgraded the wired in my whole system and caps on my speaker they gave the system a tube like quality. I’ve been skipping the tube in the preamp and the difference in sound is almost minimal. I think I would have a hard time a/b the difference. 
What is meant by 'I’ve upgraded the wired in my whole system'?
Did you replace all the wire in your power amplifier, DAC and speakers??
Or just the interconnect cables?
replaced all IC, and speaker cables. 
Still don’t quite do you “bypass” the preamp? Do you have some sort of switch ahead of your amplifier and you switch between the preamp and direct DAC connection and use the DAC volume control?
@thewatcher101 - Please list the pre-amp you are using.