# multi channel audio in/out unit?



## wandererrob (Aug 8, 2007)

Oh Great Haunt Brain, I seek your wisdom!

My current audio setup consists of the following:

4 mp3 players, with one channel off each feeding a separate amp. This is all stacked in o central location in my shed. I've got the following audio going on in the haunt:

1) ambient music - 2 channels
2) cricket chirping
3) owl
4) wolf
5) fire crackling
6) incoherent whispers - 2 channels

It works, but it's a bit cumbersome and a pain to set up and break down.

What I'd love to find (or build) is some sort of thing where I could plug them all in and feed them all out on their own volume controlled channel. Basically, one box with several single channel amps in it. Preferably in the vicinity of 100W per channel.

Does such a thing exist?

I have a brand new set of speakers as of last season, so I'm not looking to replace those. It's the electronics at the head end.


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## Ryan Wern (Dec 3, 2009)

Here's what I do when I need more sound than I have amps/recievers for:

-I run MP3 players and/or CD players, depending on what I'm doing. 
-Take a traditional amp or stereo reciever with aux inputs. 
-Run your audio through Audacity or something like it and split the stereo tracks. Example would be ambient music recorded to Right channel only, sound effects recorded to Left channel only
-Plug your sound source into the (R) and (L) inputs on the reciever or amp.
-PRESTO! Now you can run 2 sound tracks at once from 1 reciever. If you want more of a stereo effect, you can fake it by doing a little adjusting with Audacity with the blending of the (R) and (L) stereo channels. Speaker placement is key also. If you do split the stereo tracks, they will be MONO only, but if you place the speakers and uneven distances from the listener and maybe place some kind of obstacle (prop etc) in the path of the sound of one of the speakers, the listener will hear that delay and it will sound like a stereo recording. Also, most home recievers are only designed to handle (1) 8 ohm load per channel, so make sure you wire the speakers correctly to get that ohm load. If you have 2 8ohm speakers, wiring them in series (+ to+, - to-, then to reciever) will give you a 4ohm load on that channel. You would have to wire in parrellel (look it up, or I can send you a diagram if you need it, it's to hard to explain in words). Wiring in parrellel would give you a 16ohm load on that channel, but more ohms means less of a load. On that note, it would also allow you to run 4 speakers wired similarly off of that one channel to get an 8ohm load. Get what I'm saying? Message me if you need more clarification. I've been installing car stereos for 17 years...most of this stuff is like a jibberish to some people.
-You can control the volume on each channel OR on each speakers individually. You can buy passive volume knobs at Radio Shack last time I checked. They are just an in-line adjustable resistor that goes on the + side of the speaker wire. just ask for a volume knob.

Now, you can experiment with what I just told you and it will work to your liking, I use this method year in and year out and it works fine. Or, you can spend lots of money on a device that will do the exact same thing....hmmmmm. If you are not familiar with Audacity, it's a FREE program you can download and it's AWSOME. let me know if you need any more help


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## wandererrob (Aug 8, 2007)

Sorry, I wasn't clear in my explanation. I used Audacity as you mention. The middle four are on two mp3 players. The left and right of each mo3 player feeding a separate single channel amp. 

I have all the amps I need. I'm just trying to simplify my setup into a single unit while maintaining individual channels with individual volume control.

I've been pointed toward some stereo amplifier boards that look promising for a homebrew solution. I might be able to build a box/board with a few of those lined up side by side in a single, compact unit. Which would be the ideal.

Oh, and disturbingly, you're making perfect sense to me.

<- was a commercial satellite/audio/video systems installer in a previous life.


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## Ryan Wern (Dec 3, 2009)

wandererrob said:


> Sorry, I wasn't clear in my explanation. I used Audacity as you mention. The middle four are on two mp3 players. The left and right of each mo3 player feeding a separate single channel amp.
> 
> I have all the amps I need. I'm just trying to simplify my setup into a single unit while maintaining individual channels with individual volume control.
> 
> ...


Oh, I see! Ya you might be able to do this with a mixer too. They have multiple in/outs. Having knowledge in audio/video helps with just about everything doesn't it? I use mine all the time for haunting purposes. All I can think of is a mixing board off the top of my head. If I see anything else I'll let you know


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## wandererrob (Aug 8, 2007)

Ryan Wern said:


> Oh, I see! Ya you might be able to do this with a mixer too. They have multiple in/outs.


I didn't think mixers would output separate, amplified channels, but it appears now that they do. Thanks for pointing me in that direction



Ryan Wern said:


> Having knowledge in audio/video helps with just about everything doesn't it?


Oh, gawd yes! Like you wouldn't believe! Well, ok, maybe you would.


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## stagehand1975 (Feb 22, 2010)

You could purchase a pa mixer. Some pa mixers have multiple inputs and outputs that can be blended together and have effects added and some have built in power. The one I have has a stereo out and four group outputs and 20 inputs. Though a bit big for the average haunter. These come in many sizes and price ranges and you can find smaller ones for under a hundred.


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