I discovered Spottie by Hypnotic Brass Ensemble. It is a cover of one of the songs by Outkast.
Can someone tell me what kind of brass instrument begins at 0:09 and makes this deep sound?
This instrument is called Sousaphone.
You can check the credits on Discogs and see there is no bass guitar.
Baritone Saxophone – Uttama Hubert
Drums – Eamonn Hall
Sousaphone – Tycho Cohran
Trombone – Saiph Graves, Seba Graves
Trumpet – Amal Hubert, Gabriel Hubert, Jafar Graves, Tarik Graves
You can hear a demo here.
The group you are referring to is the Hypnotic Brass Ensemble. They have a website and a Facebook page, and a Twitter account. Why not contact them and ask them?