Splitting stage mix (with what I've got)

[gpercy1]

Hi All-
Neat forum-Here's my question (with some extra info)

Our band of 40ish ex rockers that play out 2 x a month just got to play through a primo PA system with 4 separate monitor mixes...Can you say "DIed and gone to heaven?" We are used to using our own decent PA but just running the monitors from the FOH board and living with it. Then I got an idea that we could d o the 4 monitor mix thing with the equipment we have...We run a Mackie cfx 20 for FOH but I also have a cfx 12. Our monitors are are 4 mackie srm 450s (powered). I was thinking I can use the cfx 12 and some y cables for our vocals (which is all we monitor) split those at the stage. On my cfx 12 I can then use the 2 aux sends along with the 2 fx sends with one going to each monitor speaker. Effectively each channel will then have a level control at to each speaker...I know there are some y cable issues for splitting signals but for this set up I'm hoping it will work...do you see any issues with this?

Thanks!

[Remoteness]

A simple Y split should be just fine as long as FOH and MON share the same power source.

Your concept sound good. I don’t remember if you can change the FX sends to pre fader. If not, make sure you don’t change the fader level once you set it.

Furthermore, since you’re talking about splitting just the vocals a small transformer splitter would not be so expensive. Even a few inline XFMR barrels would work out great if you encounter ground noise problems.

[gpercy1]

Next week we've got a gig we're going to try it out on...We'll let you know how it goes. Thanks for the help
GP

[Remoteness]

Sweet!

All the best to you and the band!

[aussie_techie]

if you can use a soldering iron well enough to make cables you can make your own passive splitters aswell. its just a transformer and a couple of connecters.

[gpercy1]

Well it looked good in concept...Everything worked, but with a mega-buzz throughout the system (mains and mons)...This was at a place we've played before too so I know there are no electrical issues there. As soon as I eliminated the Y cables and the monitor mixer, the issues were gone. Just running one mix from the FOH mixer via an aux send to all 4 powered monitors...actually sounds pretty good. We got to set up in the AM so I had plenty of time to fiddle with things, but it sounds to me like a ground issue...What are these barrels of which you speak? and where in the sound chain do they go? I might just have to check them out...Approx cost?

Thanks for helping me through this...

GP

[valleysound]

Were the FOH and monitor desk plugged into the same outlet(on the same breakered circuit)? Using the most convienient outlet on the wall without regard to power source will cause grounding hum and buzz issues.

[Remoteness]

Did you try lifting the ground from one of the setups?
Did you lift audio ground?
What kind of stuff did you try?

[Jim vanBergen]

1. There is a Hosa Y cable that ties pin 1 to the shell, which is a bad thing. These Y's are inherently prone to buzzes as a result, so be aware.

2. Did you Y at stage, at FOH?

3. How much cable did ou have from point A to B with the passive split in between?

4. Is it possible the Y cable is unbalanced?

5. Does your FOH desk have direct outs?

Methinks its time to lose the Mackie, personally. If thats not an option, there are reasonable splitter snakes made that might make your life significantly easier.

[gpercy1]

To answers some questions-Both mixers ran from the same power source. The y cables are 4 in 8 out approx 5 ft each...Split was at the stage end of my snake (mic cables>>>splitter>>>one to mon mixer, one to snake back to FOH. Did not try ground lift on either..may have been a simple solution as everything seemed to do what is was supposed to except for the buzz...Going to hook it all up in my basement and try again...

Any other suggestions?

Thansk for the continues support

GP

[gpercy1]

I decided to pull apart my splitter snake that I bought to see how it was wired...See if this looks funny to you.




I tried plugging a mic directly into the splitter, then tried each of the splits individually into a mixer without plugging in the other...no signal---so I figure this might be a snake that was wired for another use, like for and insert or something of that nature...can anyone tell me what it looks like to them?

Thanks again!

[Remoteness]

From what I can see in the photos -- Pin one (ground) is connected to the chassis ground. This is a serious No-No. You must isolate pin one audio ground from the connector chassis.

It's hard for me to make out the rest of the connections at this point but, in any event, pin i of the female XLR should go directly to pin 1 of the two male XLRs. Pin 2 (hot) of the female XLR should go directly to pin 2 of the two male XLRs just like pin 3 (cold) should do. That's how you wire a simple three pin XLR Y cord.

[gpercy1]

I thought it looked funky---1 wire to pin 3 wraps around pin 1 then to the chassis and there are only 2 wires in each...


To get it right I should:

pin 1 to pin 1s on splits

pin 2 to pin 2s on split

Pin 3 to Pin 3s? Or to pin 2s---your wording is slightly ambiguous


I may just use the connectors (since I've already got them) and solder some myself


Thanks again!

[Remoteness]

The cables you have are unbalanced. That is why the low (cold) pin 3 is strapped to pin 1 (ground.)

All pins should be wired one to one.

Do not cross wire anything unless you want to build a phase reverse Y cord. Cross wiring pins 2 and 3 would create a phase reverse.

Just wire it as follows.

Female XLR pin 1 to both male XLR pin 1s
Female XLR pin 2 to both male XLR pin 2s
Female XLR pin 3 to both male XLR pin 3s

Use balanced mic cable which should have three conductors.
Remember, don't solder pin 1 to the chassis lug and make sure your wiring is as clean as possible. I recommend you use heat strink tubing around each solder point.

[gpercy1]

All hail the king of Remoteness....

A-Soldering we will go...


Thanks-just what I needed

[Remoteness]

Thanks.

Instead of a Y cord, build an N cord.

Any combo is possible.

I bet you'll be the first one on your block with that adaptor.

[gpercy1]

Thanks for all the input everyone...

My Mackie CFX 12 works perfectly for our monitor mix-Used splitters from hosa that I got for about $7 on the internet. Splits sends each channell to monitor board (cfx 12) other to snake and FOH board. I put little covers on the phantom power switches on each board so they wouldn't get turned on accidentally. I run 4 mixes off the cfx12 to 4 powered monitors using the 2 aux and the 2 fx busses. Gives individual control of all vocal,keys,ac guitar, and sax through any or all of the 4 monitors. Nothing but compliments from my bandmates...Everyone hears what they want to hear...Only caveat is when we sing badly, it sounds very clear too...

Thanks for the help!

[Remoteness]

Outstanding.

...It's a beautiful thing for everyone.


Any pictures you want to share?

[gpercy1]

I'll try to take some next time we play---For now just imagine a macke cfx 12 with a lot of black spaghetti laying on and around it...