Feedback Eliminator

[madjim- with the Lord]

Hey Roy,
Being able to run pro sound is one of my curse/blessings. I have never used a feedback eliminator because they basically do what you can do with your board and a good EQ. The first factor is like you said, getting the singer to keep the mic close to their mouth. The second factor like you said is teaching then to keep their back to the speaker. The third factor is the overall volume and the fourth factor is finding the frequenccy that is giving you feedback and turning it down on the main EQ.

Here is something you can do that will help. When you get set up, run a sound check. Have somebody stand in the worst place with the mic open and turn the overall (main) volume up some. This will kick up the feedback. Once the feedback is ringing, start pulling down the EQ faders on your main EQ (32 band if possible). When You find the frequency that is causing the feedback pull that fader down and pull the faders on either side of it down just a bit. After this is done you should be able to turn the main volume down to a resonable level and make your EQ adjustments on the channel EQ's to tweek it in. By doing this you are doing what the feedback eliminator does. Oh, when folks hear the feedback, be sure to announce that they are all now sterile. This always gets a chuckle.

I Hope This Helps

Jim

[Roy Dennis]

Thanks for your information Jim. I will do some experimenting over the next few days, see if I can pinpoint the worst frequencies. Save myself a few £ at the same time.

Roy.

[madjim- with the Lord]

All the feedback eliminator does is locate the problem frequency, turn it down then turn down. You still have to adjust the main volume and EQ on each channel to tweek it in. They don't pay for themselves IMHO.

Jim

[Lonman]

Problem is with the eliminators is that how it works is it senses frequency spikes basically over a certain threshold & will cut that frequency. Now what can happen is you get a powerful singer that can naturally create these spikes without it actually being feedback, but it will still cut those frequencies which actually starts harming the sound. The cheaper ones like the Behringer are pretty much worthless in this respect. There are others that are a little spendy that actually work well when set correctly. Sabine makes a decent one & dbx also has a pretty decent one.

A good 31 band eq can be very effective & along with Jim, the ringout of the system needs to be done 3-4 times until you are at the typical volume level you would be running. Also when pulling those frequencies down, I also pull down the 2 adjacent frequencies a smidge.

[Roy Dennis]

Thanks for your reply Lonman.
As the type I was looking at were at the cheaper end like Behringer I think with the replies Ive had so far I will forget about using one and follow yours and the others advise.

Roy.

[BooBoo]

You can get a good feedback eliminator that will do the job it was intended for. The features to look for are finding one that will detect the spike in the narrowest band possible, then release it after a short amount of time. This does not take the place of EQing, but is a tool to use with it and can help provide a cleaner sound at a higher level.

Small loud rooms can be tough. One thing to do is to put sound absorption behind the stage and would do a better job than an eliminator. Many times the same sound can bounce off the fore wall then back to the back wall and into the mic in time to create the feedback. Something on the wall behind the mic can help blunt a return to the mic.

Neither will help when someone points a mic into a speaker..

[billyo]

Originally Posted by BooBoo

You can get a good feedback eliminator that will do the job it was intended for. The features to look for are finding one that will detect the spike in the narrowest band possible, then release it after a short amount of time. This does not take the place of EQing, but is a tool to use with it and can help provide a cleaner sound at a higher level.

Small loud rooms can be tough. One thing to do is to put sound absorption behind the stage and would do a better job than an eliminator. Many times the same sound can bounce off the fore wall then back to the back wall and into the mic in time to create the feedback. Something on the wall behind the mic can help blunt a return to the mic.

Neither will help when someone points a mic into a speaker..

that would add more work for him, i mean carrying , placing and tearing down those sound absorption every place he plays...sound absorption would be good if you're playing in one steady place...