4 Side channels from 2 amp channels?

[Rolyasm]

In a larger room with 2 rows of seating, is it possible to either split the Surround Output to four channels of amplification (four RCA instead of two with a "y" splitter) or to run four pair of speaker cable from 2 channels of amplification (LSurround amp out goes to 2 speakers and RSurround amp out goes to 2 speakers)? A few problems I see is that the back row would have a speaker located about 4-6 feet in front of them and to the side. It seems that would be very localized using dipole/bipoles, as the angle would be aiming almost straight at the back row. Direct Radiating might sound better in this setup, more like a movie theater? My next question is timing. I know sound travels fast, somthing like 1200 feet/ second, so it would only be milliseconds in delay between the front and rear surrounds, but that might be enough to make a difference. Is there any way to delay the rear surrounds a millisecond or two,or is it not going to be noticeable anyway? Any kind of timing device used? So questions are:
1)split the RCA outs and get two more amp channels (probably best)
or
2)add two additional surround speakers to existing 2 amp channels (safe?)
3)Is a delay needed

Thanks

Roly

Currently I am using a 7 channel amp that is 125 RMS x 7. Surround speakers would be in-wall most likely, 8 ohm, around 90dB effec.

[kirknelson]

1)split the RCA outs and get two more amp channels (probably best)

Will work fine but requires 2 additional amps.

2)add two additional surround speakers to existing 2 amp channels (safe?)

Will also work fine, just make sure your amp is stable into 4 ohms.

3)Is a delay needed

No

This is exactly what movie theaters do. They use multiple direct radiating speakers to cover the surround field.

[Rolyasm]

Thanks kirk,
Has anyone actually heard a setup using two rows and multiple speakers? I would be curious if it works better with direct radiating or bipole/dipole. I have the same question on another site and one member thinks it might cause too many cancellations using direct radiators on the walls. I know this is how movie theaters do it, but not sure what kind of equipment they are using. Thanks
Roly