They have spikes from the top 1 to few nodes of the elongated pseudobulbs. The flowers are borne in a mass just above the foliage of very upright-growing plants.
Many have D. kingianum and D. speciosum in their ancestry. If you keep searching you will find photos of very large plants of both in flower. D. speciosum can have hundreds of flowers on very long spikes, and D. kingianum dozens. The hybrids probably have fewer flowers than D. speciosum, which has more flowers than other species.
I can't find good photos of full-sized hybrid plants in bloom at shows in Australia, but maybe you can get an idea from this page:
Orchid Societies Council of Victoria Inc
Many of the hybrids can bloom from the same pseudobulbs year after year after year. Thus a large, undivided plant can make a spectacular show, because all the pseudobulbs might flower.