can i listen to multiple things thru the same speakers?

[jonathan4all]

I am very novice in this regard but what I do is I watch movies in my laptop with 30% sound and ultrasound with 50%+ sound and I check once in FrequenSee spectrum whether my ultrasound pitch is around 28 to 30 DB. At night I listen ultrasound again but this time in my nexus 7 2nd gen tablet. Sometimes headphones too !! Thats what I do .

Is it ok ? (just trying to make sure ) lol

Jonathan