Choose 2.1 or 5.1 channel sound system?

[fatalfury]

Is a 2.1 channel, 80 watt speaker+sub system powerful enough fill a very large room? Or should I go with a 5.1 channel, 140 watt. Does 5.1 channel even matter when all the speakers are in the same location?

I need to fill a rectangular art gallery (wood floors, wood walls, 1 story) with music for a dance. The set up would be located at the back of the room. An ASCII diagram:

        v    SPEAKERS    v
        v                v
        v                v
        v                v
        v                v
        v                v
People People People People People

The speakers will be at a high volume, so I want to avoid distortion as much as I can. It's got to be a simple, portable setup. I have a Logitech 2.1 channel Z-4 system and a 5.1 channel X-540. Would the 5.1 channel be a huge improvement? Or would the difference be negligible in such an environment?

Unfortunately, I can't test on-site...only in my apartment.

Thanks for any help!!

[Reverend]

If it's just for music i would stick with a 2.1

5.1 is designed more for film/TV soundtracks where you have multiple sound sources at the same time i.e. dialogue and background action noise.

[cash_site]

Like all things there are alot of variables that affect your options.

1. Is the 80W or 140W inclusive of Subwoofer? Assume Yes, and Assume 20W for the SW, the you're left with 60W/2 =30W and 120W/5 = 24W per speaker - So you can handle a higher output per speaker from the 2.1 setup, or 24W per speaker, meaning you can't drive it as hard before distortion kicks in... HOWEVER, having more speakers allows you to distribute them evenly in the room and hence don't need as much power...

2. Are you only limited to the Z-4 or X-540?? What about hiring a set of PA/studio speakers plus mixer/amp?

3. What are you using to create the sound? Your PC or external cd/dvd drive or Vinyl etc? If it's your PC, perhaps you can actually run both sets of speakers, then configure windows / sound mixer to push the sounds out to all speakers at once, thus giving you a combined power of 200W evenly distributed around the room.

4. While not a sound engineer, and dependent on the size of the room, you'll probably find the speakers just barely fill the room, and when pushed hard either sound distorted or just 'tinny'.

5. Likely will require at least 60 - 100W RMS per speaker with a good amplifier with low SNR for a proper dance hall setup (proper clubs/bars use upwards of 2 - 3 KW! that is 3000W RMS!!)

6. The 200W combined power for the Z-4 and X-540 is Peak-Peak Value, so more likely 15 - 20W RMS. See the big difference?!

Let us know how you go!

[Dehcbad25]

You want to use the 5.1 but find a way to clone the front audio to back and use 2.1 mode. (if this make sense).
Expensive receivers have zones (A and B) and this is what actually is ideal to fill a room for a dance. You don't particulary want surround, since the rear speakers would be dim in comparason with the front (This is ideal for movie sound, but not for stereo and music)
Cash is dead-on in his point 3,
Again, I have never done this, but it is what I would my goal if I were doing what you are doing. After all, you want all 4 speakers to distribute the same level of sound, so you don't generate a front or back in the room and people can disperve evenly and produce better dance room.
A Home Theather receiver would probably be nice if you have good speakers to plug to it.