Matching a Powered Mixer to Speakers?

I'm a bit embarrassed to admit how much I don't understand about live sound :P. So I'm hoping someone can clue me in a bit.

We're performing in a tavern in an upstairs (above the bar) performance space. The venue has two Peavey PV 112 speakers hanging in front of the loft from the ceiling (8 ohms with program power rating of 400 watts).

Our goal is to be able to mic a group of acoustic performers (no rock bands at this venue) in the small space such that, say, 5 musicians could all be heard above the din, WHILE also being able to hear ourselves - something we've never been able to do.

I knew the venue had a powered mixer. But I was thinking the monitor outputs on those are usually unpowered. So I bought a powered hot-spot type floor wedge (that can also fit on a mic stand if need be). HOWEVER...

It turns out the venue also has a powered mixer that I HATE. It's a Nady SPM-6300 6-Channel Powered Mixer (bipolar amplifier ” 2 x 150W RMS @ 4 ohms). There are no dedicated monitor outputs. There are 2 outputs on the back. The only way to hook up monitors is to use a switch (monitor/main) on the front that changes one of outputs on the back into the "monitor" output and the other into the "main" output. I guess you're supposed to daisy-chain the main speakers from the one output, and the same if you have more than one monitor.

When I tried to run the "monitor/main" setup and run the "monitor" output (which is one of the powered outputs on the back) into the little wedge monitor which is also powered, It was just too much. The monitor buzzed horribly even at the lowest volume setting on the monitor.

I assume this situation is because I tried running a powered signal into another powered (and very small) monitor. Correct?

The other problem was that when I ignored the monitor (thinking we couldn't use it) and switched the PA back to "Left/Right" (sends main outputs equally to both outputs in the back so you can run one to one main speaker and the other to the other speaker), we got decent sound, but could only turn it up about half way before the feedback started. The Nady has a small 5-band graphic EQ on it. And I was able to take some of the feedback down with a reduction at 250 Hz. But that only allowed us to turn things up another notch or two.

I then thought I could attach a 31-band outboard graphic EQ (Alesis). But the only Effect setup was the single Effect Send and Return on the front of the Nady. I ran that into one side of the Alesis (it's a stereo unit) and back into the Nady. But it didn't seem to have much effect. So I'm assuming I connected that incorrectly? Uggh. This is so frustrating.

What would be the cleanest, best way to connect this powered mixer to these Peavey speakers for the optimal flow of signal and power? I feel like I just don't understand enough about matching impedances, and wattages, etc. Heck, it may be that with THIS PA mixer and THESE speakers are just not ever going to work well together.

One last thing. In the past, the venue had a single studio condenser (I know!) hung about 2-3 feet out from the front of the loft and up about a foot. This year, I thought it would help to bring a stereo mount bar and hang SM 58s on it (I put 2 up there to capture a bit of a wider sweet spot for small groups) on shock mount rubber clips. But even that was not sufficient - too much distance between the performers and mics to ever get loud enough without feedback. Ultimately, I put up a single mic stand for the main performer, and with the mic aimed in between a guitarist's mouth and guitar, it worked GREAT. Suddenly the crowd could actually hear lyrics! But nobody could hear harmonies or even guitars from other performers. So I thought I'd leave the mic on a stand for the main vocal, and put two mics in a sort of X/Y formation on the bar out front (which is now about one foot out and up from the balcony railing). But that was still insufficient to amplify other performers off to the sides before terrible feedback.

I'm guessing the answer is going to come down to getting another mic stand or two and putting those up. But the space in the loft is sooo small already that I fear that will push the performers back against the wall and nobody could see them from down in the bar.

My hope is that I can find a solution that would properly amplify ALL performers (we could turn things up before the feedback starts) without having to put 3 mic stands into the small space. AND the performers would be able to hear themselves (monitor situation).

Any thoughts that might help me improve this live sound cluster &*$#!?

Thanks!
 
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Try plugging the monitors into the effect send output jack. This means you wont have any effects but you can then use the effect send control on each channel as the monitor send volume. Now if you plug your graphic between the effect send out and the monitors you can then eq any feedback or horrible frequencies out of the monitors. I actually use this setup with a small Behringer mixer that has left right and effect send, using the effect send as a monitor send and not worrying about using any effects.

Personally I would not mess with the front of house and leave it how it was set up, what the audience hears it more important then what you hear.

Alan.
 
The reality is that back in time, we often had a single microphone, and when the big band crooner sang quietly it was possible to get him up to the right level against the band playing acoustically. As soon a volume requirements went up, individuals got louder and fewer people onstage, it started to get messy. Big bands and orchestras are VERY LOUD, and your problem is a common one. Unless you can mic everything up, and the PA makes more noise that any individual, it's a mess.

Unless you can predict what will happen, it's tricky to plan. Your mixer is great for basic things, but unless you can play to it's few strengths, things go bad quickly. What you need is a decent sound person who can assess the sound, and then use the system to its maximum, low though that is. In general, starting with the loudest source, and building the weaker ones around it. Monitoring can often become louder than the PA, because the band members are nearest the noise, so need monitors to get over that.

With instruments that make noise, I'd concentrate on them first, then add in the singer, and BVs who will need the most help. Electric guitars, drums and keys and bass can be mixed by getting them to take advice from out front - not on stage. Trouble is, hey often won't - citing all kinds of reasons that really mean they could but don't want to.

Using the PA for just voices, or flutes or quiet things that need it is the real key to success. However, it get wrecked by band members who will not turn down, which is very much normal! A good ear on the sound, even if just a few faders is vital.
 
Thanks for the info!

Here is how everything shook out for the week at the venue. We ended up getting a 2nd mic stand and cable and putting 2 mics on stands so that the performers could be quite close to the mics (less than 2 feet). The most common setup was a primary performer with a guitar. One SM58 actually worked really well here for that one performer, with the mic placed sort of aiming at the neck. Voice and guitar were well blended and well amplified over the din. The 2nd mic and stand was great for either a 2nd performer with a guitar, a 2nd singer or 2-3 other singers providing harmony.

We still lacked the monitor. I tried doing what Alan suggested. But the only way the main performer could hear the monitor was if it was up on a mic stand. And when we did that, the feedback got worse. I'm assuming that the small space in the loft caused that - output of monitor went straight into the mic. It would have been more usable if there had been more space in front of the performer to put the monitor well behind the mic. But the railing of the loft made that impossible without pushing the performer back completely out of view of the audience. So we just dealt with the lack of a dedicated monitor and relied on the mains to hear ourselves. It worked well enough. Hopefully, I'll be able to come up with a better solution for next year. Thanks again!
 
If you are micing acoustic guitars on a small stage or having mics at a distance from the performer it will be near impossible to run monitors.

If you are close micing vocals and running acoustic instruments with pickups through a DI it is much more possible.

Alan.
 
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