Hummm... From Powered Monitor to Mixer board

[jonliles]

Forgive me for not using the search feature today. It's 11 PM and I just got home from a day that started in the office at 7AM and ended after rehearsal for 2 different shows.

So here's my situation:
I have a powered monitor in the pit so the orchestra can hear the piano. I also pipe the piano to FOH monitors so the singers can hear and follow with the music. I also have 2 "choir" mics (phantom power on) that is piped into a upstage monitor so theorchestra can pick up on queue lines.

I am going from a KORG Keyboard to a JBL EON Powered Monitor via a 1/4TS to XLR Connector (and that part works great). Form the out of the monitor, I go to a snake via 1 piece of new xlr (i've tried mulitple pieces here). From the snake I go into my main Peavey (circa 1987) mixing board (i've also tried multi channels on the snake). As soon as a boost my pot to a respectable level to hear the piano in either the mains or the FOH monitor, I get a buzzz.... Buzz goes away once I disconnect the out of the powered monitor (either locally at the monitor or at the board) - but then I loose the piano in the mains!

Should I try a ground lift coming from out of the monitor? Is there a way I can convert the "out" to a non-powered type?

Help - I am a light guy.

Jon

[Blah067]

If I understand you correctly...you want the piano in all monitors and FOH. Instead of using the one monitor from the keys output, run the output of the keys into the main sound board, (preferably using a DI box, which will balance the line), and then run aux sends back into the monitors...don't run instrument outs into a monitor, or monitor outs into the board...

I'm sure somebody else will clarify what I just said in a few moments...

[TimmyP1955]

Possible solution: An isolation transformer on the line between the two mixers.

Possible solution: Make sure that all the gear is plugged into the same AC outlet.

[jonliles]

Originally Posted by TimmyP1955

Possible solution: An isolation transformer on the line between the two mixers.

The Mixer and monitor are on 2 diufferent circuits.

Originally Posted by TimmyP1955

Possible solution: Make sure that all the gear is plugged into the same AC outlet.

NOt possible. Gear is more than 60 feet separated from each other ...that and I can't have students tripping over cords

[jonliles]

Originally Posted by Blah067

If I understand you correctly...you want the piano in all monitors and FOH.

Yes. But the only way I have of putting a monitor upstage is to use a power monitor locally at the keyboard.

Originally Posted by Blah067

Instead of using the one monitor from the keys output, run the output of the keys into the main sound board, (preferably using a DI box, which will balance the line), and then run aux sends back into the monitors......

Can't..lack of capacity...

Originally Posted by Blah067

don't run instrument outs into a monitor, or monitor outs into the board...

Why not? Could I substitue a guitar amp and use a balanced out? Should I try the DI box locally at the keyboard?

[TheatreImage]

I would go from the keys to a DI then to the monitor then to the mixer... that way you would have a ground lift and a balanced line. Also having the the three pieces of gear on the same phase could help as well

[Traitor800]

If you have a DI check it, a lot of DI's have a pass through on them for this exact purpose, if not I think Behringer sells one for approx $20 that does.
-Chris

[jonliles]

Just thougt I would let you guys know what I did to over come the prob.

From the Keyboard, I went into a DI via a a 1/4" TRS. From the DI box into a XLR Y cable. One leg went to the snake and to my mixer. One leg went into the monitor via a XLR to 1/4" adapter....NO HUMM!!!!!!!!!!

[Chris15]

Originally Posted by jonliles

Just thougt I would let you guys know what I did to over come the prob.

From the Keyboard, I went into a DI via a a 1/4" TRS. From the DI box into a XLR Y cable. One leg went to the snake and to my mixer. One leg went into the monitor via a XLR to 1/4" adapter....NO HUMM!!!!!!!!!!

And that my friends is why the big boys use a splitter as the first piece of equipment a signal hits when dealing with multiple consoles... Transformer Isoed splits are great for say broadcast who almost always are running off different power and no doubt some distance away.

You got your problem fixed - Yay. Alternate solution is to loop through the 6.5mm TS to feed the EON - depends whether you are feeding a long FOH run and hence get affected by the impedance losses of a Y.