Cavan put their troubles at senior level behind them to advance to the semi-finals in impressive fashion at Kingspan/Breffni Park.
The defending champions began brightly and four glorious points from Kevin Tierney helped propel them into a 0-6 to 0-1 lead.
But soon the tide turned. Cavan were held scoreless in the final 10 minutes of the half with Armagh's renaissance marked by smart points from Robbie Tasker and James Donnelly as they cut the lead to 0-6 to 0-4 at the interval.
Cavan regained the initiative on the restart as sub Chris Conroy fired low to the net after 36 minutes after a fine pass from the excellent Tierney to make it 1-8 to 0-4.
Armagh's Aidan Forker received a straight red card as tempers flared, but Tasker pulled back a goal. However, Cavan then eased away.
Scorers -- Cavan: K Tierney 0-7 (2f), C Conroy 1-0, F Flanagan, J Brady, P Leddy, PP O'Hara 0-1 each. Armagh: R Tasker 1-3 (2f), A Forker (1f), J Donnelly 0-1 each.
Cavan -- C Gilsenan; J Morris, K Brady, J McLoughlin; D Sexton, C Moynagh, M Brady; P Leddy, K Clarke; J Dillon, B Reilly, F Flanagan; P O'Connor, K Tierney, J Brady. Subs: C Conroy for
B Reilly (inj, 4), N O'Donnell for Brady (45), P King for P Leddy (49, inj), PP O'Hara for Tierney (56, inj), S Cadden for Dillon (58).
Armagh -- S O'Reilly; R McCaughley, C Hoey, B Kelly; N Rowland, D McKenna, K Nugent; J Donnelly, P Casey; A Murnin, S Campbell, M McKenna; A Forker, G McParland, R Tasker. Subs: R Grugan for McPartland (27), R Rafferty for Campbell (27), C McCafferty for ugent (35).
Ref -- F Cleary (Fermanagh).