rigging up monitors

[headoned]

Hi guy just wondered if I you could shed some light on this.

So I have been challenged with utilizing the current equipment we have to enable the music students to have some form of stage monitor when on stage.

My current idea for a workaround to this problem is as follows: (though I have yet to test it and check impedences and things)

as I only have passive speakers I figuered I need some form of power amp for an aux mix on the main desk so I have plugged the aux out of the main desk to a smalled mixer wich is powerd so that should provide amplification of the aux signal this is then linked into the patch bay which links to the stage box in the hall. I then daisy chain two monitors from the XLR socket on this stagebox.

would this function as I plan it to? or have a made a error in my calculations? or is there a more simple way?

(without buying a second power amp)

[smalljoshua]

Are you saying that you're sending speaker level signals down an XLR patch bay? Whilst this isn't going to cause sparks to fly, you're putting a lot of power down a very thin cable. You'd be better off sending the signal from the Aux in the main desk, down to the stage at line level then putting the 2nd powered mixer at the stage end and using good quality speaker cable to connect to the speakers.

 

Apart from that, there's nothing wrong with what you're doing. You could even use the EQ on the powered mixer for some very very basic feedback control if you don't have a graphic handy.

 

You could also (assuming that the powered mixer is stereo) use two channels panned hard left and hard right to amplify two separate Aux mixes for more flexibility on stage.

 

Alternatively, depending on the powered mixer in question, it may have direct inputs to the power amp section inside it that would allow you to bypass the mixer function all together and just use it as a power amp.

 

Josh

[GR1]

I agree with Josh.

[Doug Siddons]

I agree with Josh as well but would have been a lot more emphatic about not sending speaker signals down mic cables, it only needs an ooops on the powered mixer output to do serious damage

[Wilflet]

To clarify some speakers and amps (often older models) use XLR as a speaker connection, thats fine the connector itself is rated to a surprising amount.

Whats not fine is using mic string.

Speaker level XLR cables use 2 core speaker cable exactly the same as if they had NL2/4/8, jack, EP etc speaker connectors on the end (well theres not many situations you'd use 2 core and NL8, but you get the idea)

you need to find/make/buy appropriate cables to go from the amp to speaker-your patch bay almost certainly isnt using chunky enough cable for this.

And as a rule you want to keep the amp-speaker run short, so amp/powered mixer on stage and run line level down your patch bay from desk to stage.

 

 

[paulears]

Speakers would be using 1.5 or 2.5mm2 cabling and in many multicores used to provide permanent circuits for mics, there would be plenty of decimal points in the conductor sizes - often, the two cores, screen and jacket are smaller than a single 2.5mm2 conductor - so using them for loudspeaker circuits can damage them - but worse still, you could have 3 sockets with mics connected and one with speakers connected and find somebody swapping them if they are the same sex.

[headoned]

in future I think I may run some sort of extra speaker cabling just to provide that facility without the need for having a mixer down near the stage area, but this will work fine for now thanks for the help guys.

[Simon Lewis]

..... but this will work fine for now thanks for the help guys.

 

If you mean running the speaker level signal down the multicore is fine for now, then as others have said, no it's not. The main issue is you are putting a high level signal right next to the mic level input, and it is quite possible that you will set up oscillation (sometimes at ultrasonic frequencies). This can cause real damage to your mixer.

 

 

If you are temporarily placing the powered mixer near the stage - then fine!

[headoned]

I was going for the later but thanks for the concern