Hi Montychar!
A healthy ear should have no smell so i suspect your golden doodle may have a bacterial or yeast infection to the ear. How does the ear look? The skin should be nice and pink with a light coating of pale yellowish wax. A small amount of wax is part of the ear's self-cleaning system and nothing to be concerned about. However If the ears look red or have a dark brown or black discharge, or if your dog frequently shakes his head, paws at his ears or rubs them against the carpet or furniture, he needs a visit to the veterinarian to see what’s causing the problem.
If the ear looks good but is starting to become smelly then there are a few things to do in order to prevent a trip to the vets! Begin by cleaning them once a month or more often if required (Eg if you notice build up, they go swimming.)
To clean the ears, tilt your dog’s head downward with one hand and squirt a gentle cleanser recommended by your veterinarian or sold by a respectable pet shop / brand, filling the canal. Holding the ear closed, give it a nice massage, really squishing the cleanser around in there. That softens any gunk inside.
Now step back and let your dog shake. (You might want to hold a towel up between you so you don’t get splattered.) Wipe away any remaining cleanser with soft, dry gauze or tissue, not going any deeper than your first knuckle.
Keep an eye on them and see how you get on. If it is a chronic issue then i would arrange him to be seen by the vets as they may have a topical treatment that is most effective!
All the best!
Joe