Entry level sound system

[ianhornby]

Hi people

 

Can anyone offer me some advice or point me where to find advice?

 

I am an experienced electronic engineer but in industrial computing rather than sound. Our small community theatre uses a hifi amplifier for sound, giving us two sound "channels". We have a speaker switch box after it so we have speakers we call Left Front, Right Front, Left Rear and Right Rear, describing their positions stage left and stage right, front and rear of the proscenium arch. We use the front speakers for intro music and so on, and sometimes for fx, and the two rear speakers can be placed on the stage itself for fx. As I am sure you'll imagine, this setup is clumsy and inflexible.

 

I guess we need to buy some more amplification. We have mixing front end so we can fade sounds from CD, mics, computer and so on, but is there a system which fades the sound up and down on specific channels of the amplifier (and therefore its speaker)? I saw a production in anotehr theatre recently ("Communicating Doors") where the sound of bathwater running came from the onstage bathtub, the traffic noises came from outside the window and so on. Apparently they have eight channels of amplification/speakers, but searching the Internet doesn't find me any systems to do this.

 

Anyone any ideas? Thanks.

 

Ian Hornby

www.scripts4theatre.com

[themadhippy]

The magic phrase is aux sends ,on the mixing desk as well as the signal going to your main left and right channels,theres often a number of auxilary sends,these are used to feed the amps that power the location speakers,bring up the relavent aux and the sound comes out of the relavent speaker.

[Bobbsy]

Well, re-reading the OP, I think the magic word is "mixer" before we even get to Aux channels.

 

Virtually every live sound set up has a sound mixing desk at the heart of it. Once you have a mixer (depending on the size and complexity) it should give you multiple outputs being fed from various routing options on the desk. I imagine themadhippy mentioned Aux outs because even the most basic mixer should have a couple of these--but, as you get to bigger and better mixers, you will find things the "Groups" and "Matrix" feeds as well.

 

Just as an example of the sort of thing that would work for you, have a look at THIS. You could route things so the main FOH speakers are on the L/R channels and up to four spot sound effects speakers are on the Group faders, giving you easy control of six different speakers. If you need, more, then the Aux channels can give you lots more.

 

Obviously you need as many amp/speaker channels as you want different locations.

 

There are lots of different mixing desks out there but, for theatre, you tend to want more outputs than many users--super cheapie desks often emphasize extra inputs but are limiting on outputs.

[ojc123]

Here's an example of a "super-cheapie" mixer which will give you quite a bit of flexibility in terms of output. Not as good as the A&H Bobbsy suggests but a lot cheaper. We used its predecessor for School theatre for many years. It has been replaced with an A&H mixer for FoH use. The Behringer is now used as mixer for on-stage monitoring largely because it has so many output options. The Behringer gives us four separate aux outputs plus the main mix. It has sub-groups and direct-outs which give more flexibility.

 

Apparently the Behringers are difficult or impossible to repair because of the way they are built. Some people have issues with Behringer reliability but ours has proved reliable with careful use. Searching this forum will reveal considerable discussion of Behringer products.

 

There are smaller versions of this mixer. Other suppliers are available, this just came up on a famous search engine.

You might like to put an approximate location in your profile eg county. A friendly blue roomer might be able to offer help.

[Joe]

Hi Ian,

 

As well as all the comments on the need for a mixer with Aux sends you might also want to consider a product such as Show Cue System.

 

This is a PC based software package that has the ability to route audio files to multiple outputs on a suitable sound card, and then out to the speakers. It really comes into its own when you start to use it's ability to fade sounds up and down and pan left/right or front/back. These cues can be stored in the system and recalled night after night with no need to try and move faders or volume controls.

 

If you are near Reading, I'd would be more than happy to demo the system to you. I use it regularly for theatre and Corporate work.

 

Regards

 

Joe

 

The Complicated String Co.

www.cs-co.co.uk

07949 155370

[Scottish_AV_in London]

Hi people

 

Can anyone offer me some advice or point me where to find advice?

 

I am an experienced electronic engineer but in industrial computing rather than sound. Our small community theatre uses a hifi amplifier for sound, giving us two sound "channels". We have a speaker switch box after it so we have speakers we call Left Front, Right Front, Left Rear and Right Rear, describing their positions stage left and stage right, front and rear of the proscenium arch. We use the front speakers for intro music and so on, and sometimes for fx, and the two rear speakers can be placed on the stage itself for fx. As I am sure you'll imagine, this setup is clumsy and inflexible.

 

I guess we need to buy some more amplification. We have mixing front end so we can fade sounds from CD, mics, computer and so on, but is there a system which fades the sound up and down on specific channels of the amplifier (and therefore its speaker)? I saw a production in anotehr theatre recently ("Communicating Doors") where the sound of bathwater running came from the onstage bathtub, the traffic noises came from outside the window and so on. Apparently they have eight channels of amplification/speakers, but searching the Internet doesn't find me any systems to do this.

 

Anyone any ideas? Thanks.

 

Ian Hornby

www.scripts4theatre.com

 

Hi Ian,

 

The posters previously have listed some very good information regarding the mixing and routing of your different needs from the desk. But following this in the sound chain you will need an amplifier of sorts (or Self Powered Speakers) with which you can place your sound. For each send from the mixing desk you require one channel on an amplifier (or one amplifier in bridged mono, but I think this is getting a bit more complex than what your requirements are), or a small powered speaker.

 

Essentially your standard amplfier gives you a way to power 1 speaker (or a multiples there-of, depending on power ratings and impedance) per output of the amplifier. But your self powered speakers all have in built amplifiers, so as your very honest when you say you haven't much knowledge of audio and how it all works I would opt to try and attain some self powered units, as this would save you time trying to patch things together.

 

Does this help?