Which port do I use to connect external speakers and necessary changes in preferences. I plug in my headphones into the headphone jack and they work fine. When I try to plug in external speakers i cannot get them to work. The mac mini speakers are

Which port do I use to connect external speakers and necessary changes in preferences.

I plug in my headphones into the headphone jack and they work fine. When I try to plug in external speakers i cannot get them to work.

The mac mini speakers are too quiet for my hearing loss and I don't want to constantly wear headphones.

What am I doing wrong. I thought the 1st speakers I bought were not working. But new ones won't work either. I use just for sound not music, not stereo, etc.