"Un sombrero diferente."
Translation:A different hat.
In this instance I would suggest it means 'alternative'.
A common expression in English:
Look, today she's wearing a different hat. In other words, a different one to the one she would normally wear.
If someone were to say for example:
Look at that hat, that's a bit different! It would mean 'unusual' or not common.
I find it very frustrating that the audio level changes drastically within a lesson. Some phrases are loud and others I can't hear without turning up the volume....but then the loud ones are too loud. PLEASE equalize the volume levels!!!