Confused about 7.1 Formats

Jp, go to www.anthemav.com to get the specs, manual etc. on the AVM 20. If that doesn't work, go to www.sonicfrontiers.com. A 7.1 setup requires 7 speakers plus a powered subwoofer and seven channels of amplification. A 5.1 setup requires 5 speakers plus a powered subwoofer and five channels of amplification. Most good audio video preamps/processors will allow you, with menu options, to use fewer channels if you choose to do that. Since many DVD formats offer six channels of sound (subwoofer -- which is the .1, front center, front left, front right, rear left, rear right), choosing to use fewer speakers and amps will mean that you are choosing not to utilize all the info that is sent. So, going to a front right, front center, front left and subwoofer setup means that you will not hear the rear sound effects. The 7.1 setup (per my understanding), would normally still rely on the same six channels of sound provided on the DVD. An internal processor enhances the information to provide a more spacious sound field -- but there is no new information above what is on the DVD's six channels of sound. I believe that some new DVD formats allow a seventh channel which can then be split to two speakers (i.e., 6.1). I don't believe that is very prevalent today but tomorrow ...? Basically, the 7.1 allows you the opportunity to synthesize the extra channels for most DVD formats and provide you some growth for the future when new formats utilizing more channels are available (I am, however, not a fortune teller). Please check out the Anthem site for more details. Also, the www.outlawaudio.com site is very useful. Folks, I'm probably in over my head here, so please feel free to correct me.

I was on a flight this week and picked up some HT mags, Sound and Vision and one other that I can't remember, not Stereophile GHT because I sub to that one. Anyway, one of them featured the new THX Ultra2 system and explain the new 7.1 decoding and setup in great detail. You might look to find that rag and learn a great deal.

i think you have it right: a 7.1 preamp can do 7.1 and down.

I am currently running a 7.1 surround theater.There are know 7.1 dvd's as of yet but there are a few 6.1 discrete the 7.1 format is a long way off I think as there are so few 6.1 to date.I have a Denon AVR-3802 reciever wich has 110x7 watts but will not do 7.1 discrete,only 6.1 discrete and matrix and I also have a wide screen mode that claims to produce 7.1 from a 5.1 format.All and all with the 2 rear channel speakers the sound is awsome and I highly recommend using this set up as the dvd formats are improving every day.As for your set up it will cost you alot of money to do this right using amp/pre amp method becouse a 7 channel amp will run you about 3,500 dollars but if you have your hart set on that method check out B&K products.Other wise if you want to use your system mostly for home theater I would look in to audio video recievers.It will save you money and still get great sound from your movies.