sound and projector in auditorium

We need something for about 80 people.

And, I suppose we are going to need folding chairs.

My impression is that for a projector, a lot of what it can do comes down to the brightness of the bulb. A quick search on amazon is showing me a lot of stuff for about $300 in the 2700 to 3000 lumens range. Will that work?

I would like to have a portable speaker that can project sound out of a laptop for a dvd, or a microphone.

And I guess we need to come up with a decent screen too.

paul wheaton wrote:
My impression is that for a projector, a lot of what it can do comes down to the brightness of the bulb. A quick search on amazon is showing me a lot of stuff for about $300 in the 2700 to 3000 lumens range. Will that work?

What I learned in researching projectors 5 years ago was that the bulbs are very expensive and they have a limited lifespan in hours - after which they became dim. So I would be very leary of used projectors.

I made a 10'x6' projector screen a few years ago for my home theater. Simple wood frame and projector screen material I bought on ebay. Pretty simple and cheap. At this time a few show up for way less than $100.

Edited to add: For a portable speaker I would think just a guitar amp from a pawn shop with plug adapter or put your own plug on the cable. As far as projectors go consider resolution. My projector does 1080p, I had it about 16' from the screen and it made a 10' wide picture that looked awesome. It was about $3000. The bulb did burn out after a couple years and the replacement was ~$100. Not saying that is what you need, just trying to give you an idea. 720p is more than adequate for presentations and such. Myself, I would definitely consider a used projector as long as they had a return guarantee.

Maybe you could build your own? http://hackaday.com/2010/01/15/home-made-small-form-factor-led-projector/

Or have someone build it for you...

Do you already have a flat screen TV? That's what we use in my office to project things. Connect the laptop to the TV screen with a HD cable and the picture is on the TV with sound coming out of the TV speakers.

Julie

Julie Anderson wrote:Do you already have a flat screen TV? That's what we use in my office to project things. Connect the laptop to the TV screen with a HD cable and the picture is on the TV with sound coming out of the TV speakers.

Julie

We have access to a large flat screen TV, but we think that it would not be large enough for a group of 40 to 80. We want something for auditorium sized groups, so even the folks in the very back can see well.

Paul - 1/2 the equation is the projector brightness (the brighter the bulb typically the shorter the lifespan, but you can buy cheaper bulbs on the internet)

The other 1/2 of the equation is the screen. The cheapest solution for the best results is blackout cloth from the fabric store. It's a white vinyl material that will absorb/reflect 100% of the light. Stretch it over a wood fame, staple it tight, and hang it up. It helps to have the projector setup at the distance you plan to use to size the screen.

The more ambient light you can block out of the room the better your results will be. You can use Fresnel lights on the presenter that will not interfere as much with the screen.

The 300-$ option won't work in a large room with lights or windows. We have the heavy-duty version at church. Costs 10x more but there's no faking it.

You are either going to spend the money on walls/shades to make the space dark or on the $$$ projector that is outdoor bright.

BTW, you may want to consider purchasing several bulbs. We bought 2 for church and by the time the 2nd one was getting dim, the LCD was failing.

It also depends on the room, if you can dim the lights or shade the windows. Since you are going to be doing a good number of training sessions I'd spend the money for a quality projector made for business presentations. They have come down a lot in price and I'll echo what people said about extra bulbs, they are pricey.

For the sound system check out the Fender Passport systems. They are very simple, portable and reasonably rugged. Don't forget to do research on a good mic, it can make all the difference even if it isn't an expensive one. Lapel mics are good for talks.

This one has several inputs and also has a USB record feature so you can record your audio and overlay it on the video for a better sound quality than the mic on the camera.
http://www.amazon.com/Fender-Passport-500-Portable-System/dp/B00332RD1G/ref=sr_1_1?ie=UTF8&qid=1377289020&sr=8-1&keywords=fender+portable+pa+system

The Ready 2 Talk system is a common PA for tour buses. It's bluetooth compatible and super compact. Unhooks for transport in 30 seconds. It would allow you to turn any modern vehicle radio into a PA in moments. When you're leading an outdoor event, a boom box sitting at a comfortable distance could carry your voice via bluetooth with this same system. Compatible with any modern indoor PA. It's the size of a large wallet. You need one. Put a red circley thing on this topic. It's resolved. --- Well, the head set and PA part is resolved.

The guy you want to talk to is Jack. He's in the video. 1 888 695 5351 --- https://ready2talk.ca/

I really like small discreet overhead speakers. Big speakers set on a stage, blast the people in the front row and reverberations are a given. The ones on my bus give the same volume in all locations. Used ceiling tiles (not too old or they could contain asbestos) are an effective noise absorber when mounted on strings just like those expensive acoustic panels. They are often free when retail space is upgraded. Make sure they don't have anything flakey glued onto them. Mashed up, recycled paper mixed into paint can add texture. Used fabric can be stapled around them. I've supplied this stuff to music guys who are building recording studios on the cheap.

Here's a pic of the space (really a shop) that we call the auditorium.

You could put basic curtains on those windows for presentations for the day and at night, maybe wire it so you can turn off the lights directly above the screen independently.

Almost any soft, natural material will work to control echos. Wool carpets, jute wall hangings, cloth banners, wool socks for chair feet. If it looks like a fire hazard, it's probably going to absorb sound.

I often see MCs monkeying with sound equipment as they fight with poor acoustic design. They usually have to crank the volume to compensate.

Projectors will come and go. The comfort and usefulness of the space, usually comes down to sound delivery and reducing unwanted noise.

> sound... echo

Ditto. First thought was "what are those walls made of?". You guys maybe oughta solicit permie textile art - quilts, big embroidery, carpets (Yousef's Discount Organic Carpets... <g>) Kinda like those coffee shops with local artists on the wall. Might not have to be local though... Put a price tag on them and get a cut when they sell. Come to think of it, if you have TRAFFIC then you have a vending opp. Might talk with other kinds of crafty folk, see if they want to be there or have their wares displayed when your crowds come in or break up. Book sellers too. After all museum shops are well established tradition. All done totally tastefully, of course! Well now. There's a change of subject. <G>

Guess it's TBD but an idea for the floor might be saw dust (a LOT of it) spread w/a small fertilizer spreader people use for lawns; something mechanical anyway to make it fast and even. Then sweep or vac it up afterwards and voila - shop floor again. That is, if the space needs to be regularly convertible.

Rufus

Here is what I am thinking so far:

http://www.amazon.com/exec/obidos/ASIN/B00511ITEM/rs12-20
http://www.amazon.com/exec/obidos/ASIN/B000BFW6RO/rs12-20
http://www.amazon.com/exec/obidos/ASIN/B00118Q8CE/rs12-20

That looks like it is in the sweet spot--bright, luggable (but not carry-on portable), and good value. To get a little better is a big jump in price.

The PA system we got was crap. The projector and screen seem to be fine.

After sending the PA system back, I spent about two hours trying to find speakers that would have rich sound, not use too much energy, and they could double as something for my laptop in day-to-day use. These also turned out to be VERY small! They can do really loud and maintain sound quality.

So I'm unplugging them a lot, packing them somewhere else, and plugging them in. Over and over they are just the ticket.

And it is one of those things where you don't realize how lame your previous speakers are until you plug in REALLY GOOD speakers. This probably sounds stupid, but I feel when I play stuff with these speakers, it somehow feeds my soul. Big bump up in quality of life.



http://www.amazon.com/exec/obidos/ASIN/B000VKEFN2/rs12-20

derp...a bit late on this one. I remember coming across it way back when and thought.."hey, i should post a reply...this is the kind of stuff i <em>actually</em> know!" Then I got distracted and didn't. SO I'm sorry i let you buy that piece of garbage all-in-one PA thing. I'm glad your desktop powered speakers are working out and I imagine you've figured that mostly don't really need a microphone in that space if you bought the, but if you find you do this is kind of thing i'd go to in your situation. It has a microphone level input, they get stinking loud for the size of them, and they also have RCA, jack, and other input options that would allow you to run say the sound from a laptop with a powerpoint presentation or video AND the mic at the same time...you can get a cheap mic (shure SM58 knock off) pretty cheap to go with it (go figure). Also thse units now all seem to come with USB ports to plug in a thumb drive jammed with Mp3's (for the post presentation dance party. Good multipurpose units. I've bought lots over the past couple years for various installs/projects and I'll say that the ones I found cost around 150 CAN.$$$ (at addison electronics in Montreal) and are very rugged. They also have a little Equalizer, basically tone controls..Bass and Treble sometimes a Mid. This is actually VERY HANDY in rooms like this. Most of the boom/reverb or what some call echo is going to be in the lower end of the spectrum and cutting it out will always improve intelligibility in voices. Having just a wee bit of EQ to crank the low end down is worth a lot in a boomy space like a gym or big ass garage.

As for any acoustic treatment its been said already but heavy textiles, particularly heavy velour is your friend. The heavier the better since mass absorbs sound. The best way to mitigate excess sound energy bouncing around a room and really tackle more than just the higher end of the frequency spectrum is roxul/mineral wool type stuff in framed, wrapped in fabric, and hung just off the walls and as 'clouds' parallel to the floor, from the ceiling above head height. Its dense enough stuff that it can actually absorb lower frequencies - the best product seems to be roxul safe n sound but since you may have some leftovers from say.. a wofati, then maybe just go for it and see for yourself. In the past I've ripped scrap 3/4" or 1/2" ply into 3" strips and made super simple frames just big enough for the roxul to sit inside. Get some old sheets from salvation army/goodwill and wrap them up, stapling the fabric to the back of the frame and making sure the roxul is covered so as not to become airborn and destroy lungs. throw on some wire and hang em form the ceiling about an inch away form the wall. The gap is functional though hanging is just a suggestion, the can also be coupled to the wall without issue as long as the gap is there which improves the efficiency.

This is a proven technique that's used in recording studios, film and TV sets. Egg cartons do not work. Foam..even the very expensive 'acoustic' foam does very little. Heavy curtains and textiles are good for higher frequency reflections but will not get rid of the 'boom' or lower end resonant frequencies.

I'd often thought that the eco -version would be use strawbales somehow. They have similar properties...next time your in a space with hay or strawbales piled high clap your hands..they do not reflect much sound energy.

Finally you could try to do some diffusion of the sound: Irregular surfaces over the walls at odd angles. It can be done with scrappy materials, but I think given the nature of the space absorption will be far more apt. The sound energy has to go somewhere after all.

I would urge you to keep your sound system simple. what you have already will be fine for playback and if you need a mic in your space i suggest you buy a powered speaker designed to take a mic directly in and can handle more power in order to deal with the dynamics of a live signal (mic). You can often find these kinds of things on craiglist too. This may sound BOBO but don't leave it on the floor. Put it on a table or get a stand so there's a clear shot to everyone in the audience. Up against a wall and you'll get more bass. In a corner and you'd get more bass. avoid pointing it toward things it will reflect off.

hopefully some of this info is not too late!

Well, I just went through this for myself and ended up with the same projector (without looking back at this). That one is still the sweet spot for price/performance.

I'll probably get the same screen, too, but I may go with this for portability: http://www.amazon.com/Elite-Screens-F100XWH1-ezCinema-Projection/dp/B000PHLC7I/ref=cm_cr_pr_product_top

Just bought myself a new bass amp. Typical of instrument amps, for 50 watts out (peak at 80) it takes 120watts in. While I was looking for an amp for me, I came across this:


from: L & M... in Canada... check sweatwater or musicians friend in the US

I looked through close to 1000 amps of various kinds and this is the only battery powered PA style set up. It comes with a built in battery and one charge will last as much as 10 hours... depending on what you put through it. That is, you could have the level turned up pretty full, but if you aren't talking, or the mic switch is off, you will last a long time... start pushing that speaker cone around very much and battery usage will go up. This would be usable in the middle of a field (it would not seem loud, but better than just voice) so long as you were not trying to compete with a diesel It comes with a mic input as well as an instrument input (could be used with a second mic with a short cord ... 6 foot max recommended) and line inputs will take stereo in or two mono in (mixes down to one channel anyway). Small battery powered mixers are available too, if you wanted to expand such a system. I have a 4 channel unit I got years ago, but there is probably better stuff out there now. Anything that uses a "wall wart" can generally be battery powered too.

Other stuff. (these may be more likely available in the US) this one very nicely does not say what it's power output is, but has a nice mixer section. This one looks quite nice and has more power too. The case does not look real rugged though. Mixer is the same as the tvm10 And finally, the Peavey version of the tvm10.

The truth about pro audio is that none of the stuff even says anything about efficiency in the specs. What matters is the sound and having 10db (8X the power used) head room is quite common. Probably about 50% of the NEW amplifier designs for instrument amplification use tubes (guitar and bass especially) for that warm and gritty sound... use lots of power though. As a musician, my general thought for off grid has been acoustic. If you want more guitar sound... add another guitar(ist) etc. The TVM10 (above) might work well for me though, I will have to see.

The other path for low volt higher power audio is automotive amplifiers. These could not be plugged into standard PA speakers though because they are designed for very low impedance speakers. (typically 2 ohms or less) PA speakers could be used in parallel to get there, but they are designed for high peak to peak voltages to work and sound right (That is, you would be using them in a part of their non-linear range). So you would be looking at using car components and building cabinets for them. (getting old beat up, burned out pa cabinets and using car speakers in them might work too) Be warned car speakers are not designed to sound "transparent", but rather to give that "boom car" sound. Cabinet/crossover design might be able to make up for that.

Jay Peters wrote:I'm glad your desktop powered speakers are working out and I imagine you've figured that mostly don't really need a microphone in that space if you bought the, but if you find you do this

That url doesn't work... try this:

Same link as above

Ya, for a AC powered setup that looks as good as any. I would restate put them on stands above the highest head height in the audience. I would go stands over tables/shelves/whatever for security (they won't fall off on someones head) and also they won't be as likely to rattle at higher SPL. A bracket bolted to the wall with a pipe the right size would work fine too.

One more higher output battery powered unit. This one might even work over a diesel in the background. 100watts output and it comes bundled with a wireless mic and 4 channel mixer.

Note: any of these units can be paired for stereo sound. Just buy two of them.

Just one more note. ANY good music store will allow you to rent to own almost anything they sell. So you can rent it to try it out and if you like it, the rent will go towards the purchase price.

Paul bought some computer speakers that seem to be working just fine. I thought I'd share how the guys had things set up for our movie night last night. We watched Desert or Paradise by Sepp Holzer.

I spent a huge amount of time researching all of this and the research has paid off.

So here are the links to the stuff that works - in case it helps others and in the hopes that I can collect a sweet 7% from amazon:



The projector:





The screen:




The speakers:




And, I have to say, that the speakers are my favorite of the three. I've been using cheap speakers for my day to day laptop stuff for decades. And now I use these with my laptop when we aren't using them in the auditorium. And it is as if I'm grown up and allowed to have nice toys. These are relatively small and the sound quality is so good I feel not worthy to have these speakers for my personal use. I am glad that they do well in the auditorium and I can use them the rest of the time. I'm glad I put the time in to research these.

I have the same screen (well, the smaller one--only a TEN FOOT screen instead of twelve and a half) and projector and give them two thumbs up!

This is my current favorite speaker: http://www.amazon.com/Harman-Kardon-Onyx-Studio-Bluetooth/dp/B00IYR8W2O
It is bluetooth and rechargeable so you can set it up in front of the room by the screen and not worry about tripping on cords. I use it with the computer, iPad, phones--it just works. Not sure if it sounds as good as yours, but it makes setting up a room so much easier.

One gotcha--the Apple iPad to HDMI adapter lets you stream youtube, amazon video, etc. to the projector, but it also forces audio through the HDMI so you have to connect to the audio outs on the projector. The off-brand adapter for the macbook still lets me still use bluetooth for audio.

And you can re-edit my link if you want the kickback for that one, too. I consider it for the cause...