Will a high quality preamp really make a difference in sound?? Also speaker cable

Pre amps will sound different. I have had a few different preamps and they all measured and sounded different. Speaker cables not so much. I have some modest cables that are well built and sturdy. I have had many cables throughout the years and none have made a sonic impact--And how could they?

Cheers,

A wise man on this forum said, "Everything matters!"

My speakers are B&W 706s3 bookshelf speakers. Yes they are a bit on the bright side.

Another question fellas...if I were to throw a separate standalone dac into the mix, would it go between the NAD and the Cambridge audio streamer?? Little confused on this. As always thank you for all the advice in advance. 

Or would it go between my laptop and the NAD or the Cambridge?