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

Skip a preamp. It's an expensive volume control and most likely yes, it will color t the sound. 

But a good DAC with a quality analog volume control and you're set.

Audio Analog, Meitner and Playback Designs make such DAC's. 

Different preamps will normally sound different to various extents. I’d expect a “quality” pre-amp to make a difference if replacing one of low quality for sure.

I once replaced a Carver preamp with an Audio Research pre-amp.  Night and day!

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.