So my summer project is to build a (somewhat) portable projector that I can use outside on as big a screen as I can manage (I'm hopping 240"). I really don't want to invest a ton of money in a giant sound system, so I was thinking of getting a stereo FM transmitter and having the audience wear head phones (with walkmans or other portable radios). This is the transmitter I was looking at:

http://www.ramseyelectronics.com/cgi-bin/c...ction&key=FM25B

Is there a better solution to cheap portable outdoor sound?

I can't claim to have any relevant experience, but that seems like a great solution to me.
Last weekend, I went to a drive-in theater for the first time in about fifteen years, and I was disappointed to see that they still use AM with the little clip that goes to your car's antenna.

It might be just as easy to broadcast it to a boombox or even to get a pair of outdoor speakers. The problem with a lot of people at a party wearing headphones is that it defeats the concept of the party. Everyone just sits there in their own bubble, isolated by the headphones. With open air speakers you can enjoy all the fun stuff like your next door neighbor getting too hammered and all your friends telling your other friends to 'SHHHHHHHHHH"! A communal experience like an outdoor theater with friends over just begs for some outdoor speakers. You could even run them from your home unit. Wire lengths are cheap.
Or if you are really trying to be a portable movie theater, you could probably find some older guitar amps and run a pair of them. I see these pretty cheaply in the papers. Jack adapter and a run of cord from your computer to each one and BANG! Big Sound for a 100$.
I mean really, 240 inches needs some big big BIG sound! Go for the WOW! factor!

SamuraiJack

Outdoor sound is great but I would not go too overboard on sound. Remember, its not so much as the image as the overall experience of having an outdoor theater.

Having said that, my proposed outdoor system consists of some basic satellite speakers and an old dolby pro logic receiver. The sound should be just enough to cover the area (25x50), but not overwhelm it as you'll have people talking, kids running or speaking, and similar sounds normally associated with having an outdoor theater.

Your proposal of 240" roughly measures to 12x16, so you'll probably have to go the 4x8 route of plywood rather than fabric, since any light breeze will probably make the screen into a sail and there goes your outdoor ht.

I myself am going to try for a modest 165" 16x9 and using cardboard panels

Check out some of the installs here for more inspirations on having an outdoor theater

http://backyardtheater.com/forums/index.php

Have fun

Victor

I was thinking of making some small drive in theater speakers like they use to have hang in the window out of wood then paint them silver use rca cable to power them from a cheep reciver then let the kids mount the speakers on ther jeep or other toy cars.

But for now I just set a extera set of speakers on the back paito. They were free.

For that size of a screen you are going to need a bright PJ. What is your plan?

Hey folks,

Outdoor sound, from what I've experienced, is way different from indoors sound, as it disperses easily outdoors. I've played small club shows where your amp sounds way loud, yet you hit an outdoors patio or med. size stage, and all of the sudden you can't hear yourself, because the sound isn't being reflected by the walls or floor/ceiling.

I think the same thing will be going on for an outdoors movie - if you want to duplicate the look of the guy sitting in the chair in the 80's "Live or Memorex" ad, you'll need a LOT of power. Most modern movie theatres have a lot of muscle going on behind the scenes.

I wouldn't use guitar amps for film myself, as they are voiced in a fairly narrow frequency range, and would kind of sound muffled on the top end and not very bassy on the low. Anybody who's had to talk to a crowd through one will know what I mean.

I would probably look for a band selling a used P.A. or something like that. If you're planning on doing 5.1 outdoors, you'll need some way to get the signals from the receiver/decoder to the power amps, so you'd probably need a reciever with pre-outs (like some Onkyo's or Harman-Kardon's). Your average band P.A. will have two large stacks (which could be your L - R), 3 full-range stage monitors (which could be your centre and surround L-R, but you'll need to get them off the ground somehow), and some type of powered mixer (super important to make sure it has an EQ on board, or get a separate one).

The most impressive thing to most non-techies about sound is always bass, but it sucks the most power, so depending how crazy you want to get, this could get expensive for running a sub. I'd EQ for clarity in the voices around 3 - 5Khz and low-end punch around 100hz and 250hz, and that's about all I'd expect to pull out of a medium-sized outdoors movie venue.

Or just hire a guy with a piano and show B & W serials.

GENE

Still in the planning stage, but I was thinking of trying to make a really high gain screen to help with the brightness problems... The necessity for portability is high.

I'm using logitech 5500 speakers for outdoor movie nights...impressed w/ how they sound outside....