Can use speaker preout on HU to connect active sub?

[Diesel]

Hi, would like some solutions for the following:

 

1. Using stock HU directly powering front & rear speakers.

 

2. HU has RCA preouts for front & rear speakers only (no sub preout).

 

Have an active sub which i would like to add in.

 

Since the HU does not have sub pre-out, can i use either front or rear RCA preouts for connection to the active sub?

 

Thanks.

[Tanly]

u can but u need to use an active crossover else ur active sub would sound distorted trying to amplify the high frequencies

[Plastic]

But why does it need to have an active crossover? Thanks for the reply! I was also about to ask almost similar kinda question.

[Theaudiojourney]

might not need another crossover if the active sub already has a built-in high-pass filter.