Hi all... it has been a loooong time since I have been on this forum. Our high voltage electrical side has taken off so thankfully for you LV guys (or the world for that matter) I am no longer competition. But I know where the pros are if I have a question.

I am however putting in a small commercial audio system for a restaurant we are doing. Simple enough, but the owner wants to put a area on the outside patio for a DJ / live entertainment. I want to connect the DJ system to one of the inputs on the amp so the music can play inside the restaurant as well. I am not very familiar with DJ / live audio equipment. Is L/R audio or XLR or another way the best to interconnect the two?

Thanks in advance!

1. Generally, pro stuff is best kept balanced, so use xlr
2. Don't know what you have for inside equipment, so you may want to consider compressor limiter technology if you are using consumer stuff

Commercial stuff. I figured balanced was best, I just am not sure what type of outputs pro DJ and/or pro sound equipment has for easy hookup to the system.

You seriously need to consider what IS GOING TO HAPPEN when the DJ, left out of control for a moment, decides he wants more volume out of your system and so turns his up enough to damage yours. You can leave all your volume controls at 3 but he could have something that would still give you hot enough line level to bust your amp and/or speakers.

The issue of even allowing the DJ to connect came up recently. We told our client that he had asked for a background music system and we had provided one. He knows our work and he knows that a system capable of handling what a DJ would want to put out would cost much more money. He didn't want it. We made the point that he didn't get it.

If your client thinks he can use a system not designed for the high levels (and if the guy actually uses a phono cartridge, there's the HUGE transient if he accidentally drops the needle on the record), he very well might find that he will have to replace his equipment. Better to tell him now than to tell him he should replace his burned-out equipment with Pro if he wants to put on DJ shows.

I see your point, but the whole point of the setup is to have the DJ or Musician (most likely musician) playing on the patio and to have that music playing at a low level in the restaurant, constant volume. Not looking for a connection that would allow the performer to control the volume of the system. What I am looking for is the "type" of connector a musician would want to connect his pre-amp to the system and then have that connection as a source to the amp (L/R rca)

The problem is I am not familiar with musician or DJ equipment to know what type of jack they would need to connect to. I am thinking 1/4" phono jack?

...Had to chime in here. I posted a popular mixer that's used widely in the "scene". It's been a long time since we were limited to a single format.

 Typical DJ mixers will have both balanced and unbalanced out. Take the balanced out, run it to a compressor/limiter, and then to the 70V system. I wouldn't run a live sound signal into a background music system without dynamic control - compression AND a hard limiter. I like DBX gear, or RDL if you need something small. 

If you haven't purchased gear for the interior yet, consider something that has limiting built in, like a Crown CDi series. 

Take a look at the specs on the Zone Pro line from DBX. [Link: dbxpro.com]

This will give you a lot of knowledge about the possibilities of sound control from other sources such as a DJ or live musician. Add a Crown CDi series amp and you have a great restaurant system that's very flexible.

A far as DJ mixer outputs you will want to be prepared for;

-Unbalanced mixer outputs: line level, typically RCA connectors ... and,
-Balanced mixer outputs: can be either XLR or 1/4" TRS connectors

Commercial mixers have a variety of input configurations. Bogen, Atlas and others offer powered mixers with both line level and balanced inputs but offer very limited sound shaping tools for EQ, Limiting ...etc. A preamp product like the one mentioned by DBX allows you to control/shape/restrict the sound as it enters your mixer and amp, and directly avoid some of the sound level risks that Ernie, Deuce, and Fred were describing.

I could count on one hand the DJs around here still using records. The ones under 25 dont even know what those big vinyl discs are.

And just leave a set of RCA inputs, every DJ mixer I have seen from the cheapest to the most expensive still has a set of them. These will 'usually' be at a more consistent output level than XLRs from different decks.

Thanks. This is kind of what I planned on doing. And thanks to everyone else for their help.

I want to plan for most scenarios, but when we are talking DJ / Musician we are talking probably a guy with a guitar / mic / amp or a DJ spinning some Frank Sinatra. The place is kind of a classical Italian joint. I do want to be careful though, in case the guy throws a New Years Eve party and hires some hack DJ with a laptop and a bunch of amplifiers...