Sorry that I didn't see this post earlier. WA7 + WA7tp pairs very well with TH900. We use this combo at trade shows with wonderful results. WA7 system pairs well with your HD800 too! So it's a win win. I think WA7 + WA7tp would suit your needs more than WA22 + WDS-1. When you're ready to change up the tubes, we offer and upgrade set on our web site. I think you'll be pleased with a WA7 system.