How to get a Tube Tone from a Line 6 Bass Pod XT

[basssoundbass]

My current set up is quite simple I have a Hartke LH500 and a 1 x 15in Barefaced Compact Cab. The sould is clear and clean.

I am looking for a more tube like sound and have a Line 6 Bass Pod XT.

Any ideas on how I could easily get a more tube like sound using the Bass Pod XT with the LH500 and my existing Cabinet?

Thanks.