Our IW pup went to the vet today with yeast in both ears. It is a brown waxy buildup, the ear is red and warm to the touch. It smells sort of sour. In severe cases that I have seen when I volunteer at the Humane society and pound, the dog had hair loss and the ear was really swollen, like a sausage and very painful.
With ear mites I haven't seen as much warmth on the ears, and like someone else said it is more grainy looking, sometimes dry and flaky. They also shake their head a lot.
For the Yeast my vet gave me Mometamax 15GM, 8 drops in each ear. They already look less irritated.