Feedback Destroyers

[Randy]

Do they work? :shrug

I use a Sennheiser UHF Wireless Handheld Mic EW-135-A, the receiver is mounted inside my gear case. I have had trouble with best man walking around doing their toast and getting too close to speakers, also had a best man turn off my mic causing some nasty noise. This of course makes us look bad. I have been fighting this issue for some time now and somehow it must stop. Will a feedback destroyer fix this problem? My main's are on stands and run an 18" sub on the floor under or beside one stand.

Thanks for your help.

[SirWolfy]

I know the DBX DriveRack PA serves numerous functions, including the elimination of feedback. However you must also purchase the reference mic to fully set up the system / unit for each gig. I do like the idea that this unit consolidates several signal processing components into one compact rack space and costs less than buying all of the components separately.

[Thomas Hamkens]

You don't need the RTA mic to use the feedback eliminator on the DRPA. Actually, you don't use the RTA mic for that function. The only function you use the RTA mic for is the auto-EQ. I've found that proper mic EQ and technique work far better than using any feedback eliminator.

[djdonny]

<div class='quotetop'>QUOTE</div><div class='quotemain'>proper mic EQ[/b][/quote]

What is the proper mic EQ? Technique only goes so far, especially when handing the mic over to a guest. Sometimes, though, my own MC or assistant forgets to mute the mic before walking in front of the speaker. I've never found an EQ setting that has much effect on reducing feedback. How do you set yours?

[Wolfie]

Cheers, Randy.

We have had excellent feedback rejection results by using a compressor/limiter in our system chain. While it is true that the EQ should be tweaked to handle harmonics from your mics, a C/L can help with mic feedback.

We had a best man give the toast at a wedding recently. When he returned to give the mic back he raised it over his head while walking past the top cabs. I heard a slight hum and that was that. Later, just out of curiosity I bypasssed the C/L and tried it myself. The resulting feedback honk tripped the breaker on the Furman and shut the system down.

I hope it helps.

[Randy]

After reading the replys, I was thinking of how my EQ was set up. I run a 30 band, (15 per ch.), and had a sound man set it up. The EQ was set high in the 20 and 10 range of the low end for best sub response, I am going to try backing them down today and see if this makes a big difference.

I have been looking into a compressor/limiter for sound control, could there be a double use for this type of unit?

Thanks Sir Wolfy, Thomas Hamkens, DJ Donny and Wolfie for your response, I will be looking forword to hearing more on this topic.

[Wolfie]

Yup, a C/L can really help with peak volume control.

You can spend a lot of money on a C/L but the high-end models tend to be overkill for a DJ or KJ company. It's the limiting capability that can save your bacon in a venue that has strict volume level requirements.

The DriveRack is a nice, "all-in-one" component that is very easy to set up and use. Rather than buy, tweak and transport several processors you may use a DriveRack to make setting up much easier.

The thing many of us in this business miss: When we key the mic we're doing live sound. Mics do exactly what they're designed to do -- receive sounds and send them to amplification. Feedback occurs when the mic is picking up frequencies that can "ring" due to existing acoustics. The more powerful the sound system, the more opportunity for mic feedback.

I recommend starting with all EQ bands set to zero or mid-range. If you have to boost the low and high bands to get a good tone, it may be because your speaker system isn't capable of reproducing those frequencies well. If this is the case you may wish to look into a bi-or tri-amped system in the future.

Your EQ can be set to tweak out ringing frequencies. You may wish to lower or cut a couple of adjacent EQ bands to stop the ring. Once that's set you can usually leave it set. Every system is different so use your own judgement and do what works best for you.

Generally speaking, you may have to cut your mic's low level at the mixer. Most pro mics can reproduce frequencies at 40 Hz. That's usually well below the capabilities of the human voice. You likely don't need a booming voice. Cutting the lows on your mic channel will help to reduce feedback as well.

I hope it helps.

[karaokedj]

Originally posted by Randy@Aug 7 2005, 09:31 AM
Do they work? :shrug

I use a Sennheiser UHF Wireless Handheld Mic EW-135-A, the receiver is mounted inside my gear case. I have had trouble with best man walking around doing their toast and getting too close to speakers, also had a best man turn off my mic causing some nasty noise. This of course makes us look bad. I have been fighting this issue for some time now and somehow it must stop. Will a feedback destroyer fix this problem? My main's are on stands and run an 18" sub on the floor under or beside one stand.

Thanks for your help.

I use a Sennheiser UHF Wireless Handheld Mic EW-135-A, the receiver is mounted inside my gear case. I have the same problem when the mike is turned off.I think the company is a ware of this problem.You need to contac the Sennheiser and tell them of your problem.I have theSennheiser head mike and I have no problem around spkrs or turning the unit off at the belt receiver.

[DJSlatz]

I use a wireless handheld and headset (both UHF) in each of my racks. No problems with the handheld normally as it is usually away from my system however, the Countryman E6 headset is another story.
The feedback from this one, even in the super-cardioid configuration was a problem so I put a Sabine Sl-820 feedback eliminator in line with it ..... problem resolved!

DJSlatz

[KJDJ]

Behringer SARC DSP. Feedback elimination, compress/limiter, digital high pass filter. for $69. I never give a wireless to a bride or daddy without it!

The problem with the drivrack is the feedback eliminator EQ the whole mix.

You want just to EQ the mic.