All three digital radio companies enjoy solid backing. XM's partners include DirecTV and Clear Channel Communications. Most of the big names in audio are developing digital car radios. Sony displayed a prototype that can be removed from the dashboard for home use. But XM and Sirius are focusing on cars.
Cars are noisy listening areas, so the emphasis is on content over sound quality.
They say the digital dial is big enough for both of them. It's a very large market. That's why we have competition.