However, Dowson insists his side were not drawing motivation from that defeat.
“I think you’re always going to be disappointed after a final and they have the privilege to celebrate however they want to,” he told BBC Radio Northampton.
“I gave them kudos and credit in the post-match interview and I still would do that and we’ve got to make sure we prepare for this game and not re-analyse that one.”
Northampton’s run to last year’s final was built on famous away-day victories, beating South African side Bulls at altitude in Pretoria in the pool stages before upsetting Leinster at Dublin’s Aviva Stadium.
Bordeaux Begles have won seven of their eight home games this season, and start the game as favourites with the bookmakers.
However, Northampton back Tommy Freeman says his side want to modify their underdog mindset and a reputation for a style based mainly on running rugby.
“I had a conversation earlier with Ollie, our sports psychologist about the perception we give or we’re giving,” the 24-year-old England international said.
“We’ve always had the young card – we’ve got young players, promising players – and the narrative’s got to change. We are what we are and we’re physical.
“You’ve seen that over the last few weeks, how physical the forwards are.
“We get that underdog status probably a bit too much. We are trying to change the narrative so its’ ‘we’re the big dogs and this is what we’re going to do’.
“We need to puff our chests out and rip in.”