Help Feedback!!

[bcbeak]

Had our first full band rehearsal tonight with Dl1608 and new DLM speakers. Everything was great (accept)
our singers wireless mic had massive feedback issues in the mains. I cut effects, comp, gate, EQ .. nothing ..
still feedback city. We had to keep it so low it barely cut over the stage volume. '

I am not a sound man .. just a guitarist running the ipad from the stage ,, so any advice would be appreciated.
How do I debug this issue? I tried SOLO and muting all other channels .. but it seemed like the feedback was
when all the other mics came on in conjunction with the singers mic... Im hoping for some suggestions before our gig tomorrow night.
Thanks

[ijpengelly]

Where were the mains in relation to the singer? In front, behind, to the side? Without more detail about the venue and set ups I think we can only shoot in the dark with responses, which isn't all that helpful to you.

Tell us about the set up you were using, the venue and layout of your gear and the nature of the feedback (low freq, high frequency, etc.).

Thanks.

[bcbeak]

We rehearsed in a mostly empty bar .. with an average stage. Our speakers (Mackie DLM12's) were posted only about 5 feet in front of us
and to the side .. (kinda close) ...  We have the DLM12S sub too with only bass and drums in it. The feedback seemed to be some low rumble
but also some very high pitch squeal.   Even flat EQ and no effects or anything .. just feedback. Wireless Digital Mic. (not sure what kind).
I ruled out any stage monitors (they were off at the time) ... but do suspect some interaction with other miss (drum) behind the singer

[Ampli]

Hi
An option is :
get on youre smart phone an rta app (there are lots of free one see the topic)
Then put directly pointing at the monitor
Open up the gain to ca 12 o'clock
Put the main fader of the aux that controles the monitor al the way down
Put the channel fader that controles the mic to 0 db
Now open in the main aux fader the geq
The care fully slide the main aux fader up till u got feedback and watch the rta app on what freq this is
Then pul in the geq this freq down and check if the feedback is gone
Raise the main aux fade more and check if there is other feedback freq
I normaly do this till i have no feedback any more and a monitor level that i want
Usely i have the gain more or less put on 0 db, the mic fadere at 0 db and the aux main at 0 db
And no feedback
Use a split cable if u want compressor on the mic channel (  u use 2 channels then 1 for the main pa and one for the monitor )
On the lr tab u leave  the channel for the mon down
That wAy u canuse compresn and no problem with feedback

Ofcouse the above u need also to ring out the main

Goodluck
Marco

[robbocurry]

I think you need to get a sound guy in, even for just one gig/rehearsal to get you a basic sound. It would be money well spent and would give you a good starting point. 

[sam.spoons]

+1

However, the first thing to try is a different mic, wireless mics can be a law unto themselves so try a known, wired mic instead at least 'till you have identified the problem.

Does the problem occur when, 1/ foldback is up with no mains, 2/ mains up with no fb, 3/ only when both mains and fb up? Try all combinations to isolate the problem.

You say it's an empty bar, so possibly an echoey room and you don't say where the DLM12's are pointing, towards or away from the band?

You mention the feedback being related to having other mics open, this is a well documented effect, the more open mics the more potential for feedback but does the feedback continue if you mute the singers mic with the others still open?

[Jerrylee]

Not too be rude, even though most of you will take it this way, there are plenty of ways of ringing out feedback. Sounds like your issue is user related. Do some web research and even check YouTube. You will find hundreds of articles and lots of videos of how to accomplish this. They talk about lots of things from mic and speaker placement to ringing out with eqs. Why hire a sound man when tons of them have posted tutorials on how to fix your problem. This is why it was also suggested to Mackie to add parametric eqs to the outs. It make ringing out feedback a lot easier than using geqs. And you can really zero in on your problem frequencies. Also after a while of ringing out feedback you will start to hear what frequencies are causing problems. At that point zeroing in on them becomes much faster.

[Trshot]

Not too be rude, even though most of you will take it this way, there are plenty of ways of ringing out feedback. Sounds like your issue is user related. Do some web research and even check YouTube. You will find hundreds of articles and lots of videos of how to accomplish this. They talk about lots of things from mic and speaker placement to ringing out with eqs. Why hire a sound man when tons of them have posted tutorials on how to fix your problem. This is why it was also suggested to Mackie to add parametric eqs to the outs. It make ringing out feedback a lot easier than using geqs. And you can really zero in on your problem frequencies. Also after a while of ringing out feedback you will start to hear what frequencies are causing problems. At that point zeroing in on them becomes much faster.

Agreed JL,
We need more info here....Ampli, it's not monitor feedback it's the mains, he said mon's were off.
The first thing you need to do is isolate the channel/s causing feedback. You mentioned,"it seemed like the feedback was when all the other mics came on in conjunction with the singers mic".  Was it all the mic's or the wireless mic feeding back? Where are the input gain/s on the suspect channel/s?

[Kevin]

The first thing you need to do is isolate the channel/s causing feedback.

Yes, you can usually use the solo bus for this. Solo each of your mic channels. One will usually have much louder feedback tone than the others. that one is your problem. Use headphones for now. For future, get your self an attenuator cable like this so you can run to solo bus to an RTA on your iPad.
http://www.kvconnection.com/product-p/km-iphone-mic42-a22.htm

I agree with Sam on eliminating the wireless mic first to see if that stops the problem and then work from there.

And check batteries in your wireless and/or anything else that uses them

Good luck.

[bcbeak]

Last week I reported feedback trouble with my first rehearsal. This continued on Friday night at our first gig.
We could not get our lead singer mic loud enough to hear over drums and loud guitar without feedback. I rode
the fader all night with him (I'm supposed to be playing instruments not running sound) and we limped through the
night. This was perhaps the worst PA sound disaster I can remember.

I tried everything I could think of to ... flat eq, no eq, no effects, no dynamics .. etc. but I could not solve the problem. We
managed to get a little more volume by adding one of our floor monitors to the mains.

Later at home, I spent several hours working with the board  (again I am no sound guy) .. and I found what I think is a bug.
During the gig .. I could not get to the dynamics page from the EQ screen for the LR bus.  No matter how I slid my fingers, right left
up down, one two three fingers .. the EQ screen would not take me to the dynamics. All of a sudden at home .. I got it to work after about 50
tries .. and I found that the Compressor was on .. with a high gain setting. This most likely was the source of the feedback right?

I am going to try again on Thursday at rehearsal with a zeroed board, focusing only only getting a good loud microphone for the lead singer.
I have read all of your posts on "ringing out feedback" ... this is over my head and beyond the ability of time that I have for setup. I am a musician
that needs an hour to setup my own gear and tune. I do not have time to ring monitors for an hour .. that is why we bought this PA setup .. because
it was supposed to be easy, portable trouble-free and set and forget. 

I have never had this level of frustration with gear. Even cheap gear which although never perfect .. can usually perform as expected with getting
a PA volume for mics up quickly and easily.  (i.e. turn the thing on ... and slide the channels up) I am expecting to get some help from a friend, but If that rehearsal does not go well ... this mixer will be on ebay Friday.

[Kevin]

and I found that the Compressor was on .. with a high gain setting. This most likely was the source of the feedback right?

That could do it. You'll want to check the compressor settings in the inputs as well, esp if using monitors.

I could not get to the dynamics page from the EQ screen for the LR bus.

You've got to put your finger on a grey area and scroll down. Its non intuitive, but works.

I have never had this level of frustration with gear.

I will second that, but I would also add that I've also never had a piece of gear that made my life so much easier - once I figured it out. Keep in mind that this thing is half mixer and half computer and the part that is half computer has a bit of a learning curve.

[jlb]

This is a digital board. Putting compressors, gates, parametric EQ, FX etc in the hands of the inexperienced is a recipe for disaster. There are going to be many frustrated users popping up. Thinking this is a plug and play piece of gear is going to be a big disappointment for many.

[RoadRanger]

If you go to "shows" and recall the default snapshot you're in pretty good shape to start but I'd not have the comps and gates enabled on the inputs and have the "no clip" preset on all the output compressors. When Mackie gives us a way to share shows, snapshots, and presets I'll publish my defaults . I suppose I could write them up in a post or ten ...

[bcbeak]

I Wanted to post an update on our issues with the DL1608 and DLM series speakers.  We had a professional soundman
work with us tonight at rehearsal. We spent 3 hours .. just setting up the board from scratch. He dove right in .. even though
I don't think he had a lot of experience with the board ... pretty impressive. He worked EQs on every mix and instrument over
and over until each was set to nearly zero on the meters and each instrument or mike had its own slice of the spectrum.

He panned instruments, added effects, and got maximum volume from the setup with no feedback whatsover. The band sounded
as good as any pro audio setup I have played in in years and there seemed to be great clarity on stage. We have 4 vocals, drums,
bass, three electric guitars, pedal steel, fiddle and banjo all in the mix.

We worked through all the monitor mixes and he set us straight on vocal monitors ... setting all four singers to even levels in the
wedges to promote balanced harmonies. Not a lead singer and everyone else complaining for more volume .. the vocals were crystal clear.

We saved the mix in a Show/Scene and have a great mix to use as a basis for all our shows.

When he was done and walked me through the changes, I was astonished to see he did the opposite of what I had
attempted to raise headroom and cut feedback. Instead of my Smiley gain EQ .. he had a smiley cut EQ.

For those of you who are true sound technicians .. kudos to you .. you really have a lot of skill that us weekend
warriors do not. For those of you who are band members running sound from the stage with little pro audio experience,
I highly encourage you to get the assistance of a professional if you are having any trouble with your setup.
I am so happy that we did. The DL1608 is a remarkably powerful tool, but in the wrong hands it can be unwieldy
and its easy to lose whats going on inside the box.

[sam.spoons]

Good to hear you have got you're sound sorted. How about some screen shots of the main settings?