No, but you can cross the subs over lower with larger speakers.
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I would not advise this - that 3" polydome mid was discontinued - it won't play loud enough for you space requirements - you will suffer terrible midrange compression and difficulty to hear dialogue on movies in such a large space or worse you will blow them up.
There is a replacement but it looks Mickey mouse
Have you considered panels to reduce the room size across the middle and hanging baffles from the ceiling - it is a very long room (like a tunnel) and you may end up with very long reverberations as you get in a church or gymnasium ( you say it is concrete). The mirror glass on one side will also act as a very strong reflector.
Narrow dispersion type designs or horns might be your best bet (you probably will benefit from limited dispersion and the higher SPL that horns can achieve)
A few things. " taking advantage of the HD Audio formats" has nothing to do with 7.1.
Secondly, to take advantage of any HT audio format, you really want to match your center to your mains as far as driver types and sizes. It sounds like you have four full range monsters right now and no sub. Thats a problem for current audio tracks on DVDs as it stands, although I am sure the four channels sound great. The center channel, usually the dialog channel ---is key.
Anyway, movie sound tracks are engineered with a sub in mind, thus the ".1" in 5.1, 6.1 or 7.1.
So no you dont need full range speakers with subs and its not actually desirable for Home Theater. Most DVD sound tracks are designed to crossover at 80 HZ and thats the standard setting for most AV receivers. With fuller range speakers, including the centr channel, you could cross at 60 or even 40. My center channel extends to 45 HZ, so I could probably cross at 60 hz and be OK all the way around, including the surrounds.