Will a phono pre-amp make a substantial difference

Yes.

My goodness; so much unsolicited advice and advancement of personal preferences to dazzle and befuddle the OP!  "Yes" was the best answer given; we all need to remember that any AI responses (now and in the future) are fed as much on marketing hype as they are on reviews and objective observations.

@fatdaddy2 “AI responses”

Totally with you on calling out AI reviews.

There are people who believe AI reviews!

Has AI now grown artificial human ears?

And yes, there has been enough said to “dazzle and befuddle the OP” already without AI which can say anything, and is ultimately accountable to no one.

I compared the Rega mm/mc against a built in phono in a receiver and couldn’t tell much difference. Then i tried Rogue audio with tubes and separate power supply. What a difference. But that is priced over 2 grand

@mylogic

AI which can say anything, and is ultimately accountable to no one

Your logic is probably based on the same sort of neural network that large-language AI models are based on, but is probably less able to succinctly summarise in neutral ways. 

I personally find it astounding how helpful AI can be in many different situations.  Ai will not say anything that has not been said before, and the fortunes of the technocrats currently investing billions depend on how we humans accept what their competing AI models produce.  The authors of these models are accountable to their bosses and the shareholders that back them.  AI is currently the biggest enterprise in play.