I think my dad used electric lamp cable until the early 1980s,
when he got redundancy money
and treated himself to 'special' speaker cable
to cheer himself up on losing his job...

I hope he at least thought he heard an improvement...???

Back in the late 70s - early 90s, I used whatever cable my dad had left over..
No questions asked, I didn't know or care much about finer technicalities back then...

Now I'd just do a google search for best value for money 'speaker cable'...