Setting up a faux 6.1 system...help (1 Viewer)

[Aaron Garman]

Hello all. At my college, I am involved with a film club and for our last event of the year we are going to have a Lord of the Rings festival. Part of this will consist of viewing the extended edition DVD's. For this special event, I have elected to setup my home theater system. However, since I will have a good size room at the school, I'd like to use more than two surrounds. I have extra speakers and amps to make this possible. I was thinking about doing the THX setup: 2 side surrounds and 2 back surrounds. Now, all I have is a 5.1 reciever but I have preouts for all channels. Now to my knowledge, I can send the info from the LR surrounds to a separate prologic reciever (I also have) and set it to 3 channel prologic to create a faked Surround EX. This would equal 3 surrounds total: LS, CS, and RS. Now, is there a way to use 2 speakers on the CS with this particular setup? Even if this is not possible, can I merely have 4 surrounds total (2 for LS and 2 for RS)? How would I wire such a system? Thanks for the help everyone.

AJG

 

[Ian_J]

I have no idea but I'd love to hear a reply.

 

[Aaron Garman]

Me too!

AJG

 

[Stephen Hopkins]

You can do EXACTLY what you described and it's probably your best bet to get matrixed ES/EX since you have all the equipment mentioned. People have been doing this for quite awhile but interest in it has dies down as ES/EX encoding and amplification has worked it's way down in to reasonably priced entry level receivers. It's easy to use 2 speakers for the surround back, just wire the 2 in series (or parallel if your receiver can handle the lower impedance). Having 2 speakers in the back can help minimize over-the-top effect (your hearing can't really distinguish the direction of sounds directly behind you and it can make those sounds sound like they're coming from in front of you).

You could wire 2 speakers to each surround output (in parallel if your receiver can handle the lower impedance, in series if not) but having the same sound coming from behind you and beside you would muddy the sound field and make effects sound like they're coming from somewhere other than where they are intended.

Sounds to me like matrixing the EX/ES channels using your pro-logic receiver and using 2 back surrounds is your best option. To be honest it's not real "fake" EX/ES since the pro-logic decoder is using the nearly the exact same processing that is done to decode matrixed EX/ES tracks on actual EX/ES capable equipment. It's real matrix EX/ES, just not all in one box.

Hope this helps

 

[Aaron Garman]

Thanks! I'll give it a shot.

AJG

 

[Aaron Garman]

Just a clarification. When hooking up the four speakers, I will hook up the side left to the left channel on the prologic reciever and the right surround to the right channel. Now, if I'm to use 2 speakers for the surround back, do I hook both up to the center channel out on the reciever? Does the positive lead from each speaker go into the positive input, and vice versa for the negative? Thanks again!

AJG

 

[Stephen Hopkins]

Hook the pre-outs from the main receiver to any L/R input on the pro-logic receiver. Set the pro-logic receiver to the propper input and set it to pro-logic 3 mode. Connect the left and right surrounds to the MAIN left and right outputs. Connect the back surround(s) to the CENTER output on the pro-logic receiver.

For wirring 2 surround back speakers you're probably going to want to wire them in series... + from receiver to + on back speaker a... - on back speaker a to + on back speaker b... - on back speaker b to - on receiver. This will present a 16ohm load to the receiver (assuming you're using 8ohm speakers). If you wired in parallell (both speakers directly to the + and - of the receiver) you would present a 4ohm load and if the pro-logic receiver can't handle this impedance you risk straining/damaging the amplifier or causing it to shut down.

Hope this helps

 

[Aaron Garman]

Clear as crystal. Thanks much!

AJG