Do speaker cables really make a difference ?

Depending on your system, YES. My garage system is an old boom box with inputs and a removable powercord, but I doubt I’d notice much difference changing the PC.

Back in the days of yore everybody used lamp cord - and nobody complained!

Back in the day we used carrier horse & pigeons for transport and nobody complained.....

@thyname

Touché

They do make difference, but if compared 10k Nordost with lamp cord, you really wouldn't know what sounds better if blind A/B. 

Try doing a blind A/B with 100 of your favorite recordings and you may hear a difference.

@dweller you can multiply it by another 100 -- make it 10,000 as in my case, but the fact will remain the fact -- you won’t know which one sounded better on which wire and on which record $10k or $10.