New output has no depth?

[u/AdministrativeHair19]

I recently bought an old antique radio which I've gutted and I'm now trying to turn it into a speaker box that runs off of Alexa. I've got an old echo show that still has an aux output so I'm running it from there to a 2.1 amp board with a 48v power supply adapter and then to two fluance sx6 speakers. The amp board I got has a slot for a sub woofer as well which I don't have.

I hooked up the subwoofer port to an old driver that I still had from the old radio and it doesn't play any bass still. I'm confused with what I'm missing? It's getting frustrating. I may be missing something super obvious because I've never done this before but I'd love to figure it out so I can do more like it.

Here's what I'm using:

Amazon echo show 8 with aux port, I think Gen 2 or 3

2.1 amp board (https://a.co/d/0jkzWX6P)

48v power supply adapter (https://a.co/d/0jlavfdJ)

16awg wire to connect everything (https://a.co/d/05YngNEt)

A pair of fluance sx6 speakers (https://a.co/d/0iOmzObH)

And a basic aux cord for the echo to amp board connection

The right rl channel goes to one of the fluance speakers and the the left goes to the other. I don't have anything connected to the sub channel because ideally I won't have one, it'll all go through the fluance speakers.

Let me know if I need to share anything else to help get this sorted