feedback

alter ego's

i wonder if anyone out there could explain a couple of things to me and maybe give me some tips on how to eliminate feedback?I have the afs switched on and have 6 live filters.I am still getting feedback through the microphones,I do not have the correct dbx mic to properly go through the eq wizard,is there anyway round?Am also a little confused as to how to set the filters as it can be for speech or music medium high etc and how long to set the filters for?Any help would be gratefully received as don't seem to be able to get it to do its job!

Just a quick up date as I was't too specific about my equipment,I run a chevin amp 1600 w per side,2 logic system x24 top caps with 12\" drivers and 2 \" horns and the very large 2 times 15\"driver per side logic system bass bins.I only use in ear monitors,we have 2 sennheiser cordless mics.Mackie desk.All the music comes from a laptop with seperate sound card.Also wondered when I finally get it set right if I have to set the afs every gig?Obviously not 1 piece of my equipment is in the pre sets so have to use the custom options.

Dra

Make sure that you have set up the gain structure as described in the back of the manual and on the forum. Try this, set all the the filters to fixed and set for speech (widest notching). Then try the same at music low (next widest) and so on up through music high (narrowest notch). Which ever seems to give you the best sound with the most volume (emphasis on sound), go with that setting. I usually use music low with 8 fixed and then change the live filters to speech. Speech will catch feedback the quickest. Set the \"reset live after\" to 20 or 30 seconds. If the same frequency keep being pulled out by the live filter then re-do the wizard and increase the fixed by one and try again. If you can get your hands on a charting of the speaker response from the manufacturer, you can fix some of the problems with the Post PEQ's. If you can, borrow a reference mic or worst case an SM81 (download the gragh and compensate accordingly), do Gary's indoor EQ method. Search it out on the Former Forum above. But be sure to read up on the entire subject. The important thing is to have your speakers reproducing content the same as they receive it. Then do AFS after. Last resort use the GEQ. If you can't seem to make any improvements, post back with cabinets, mics, room size and shape, surface types, etc.

DRA

Gadget

Without knowing how you set the feedback eliminator all I can do is start from scratch.. and no there is no way around a measurement mic...

make sure that the speakers are far enough in front of the mics that the mics can't \"see\" the speakers

get the energy from the speakers on the people and off the reflective surfaces

set everything up and get all mics roughed in FOH and monitors

Try and ring out the monitors first and make sure they aren't the problem

once everything is set up select \"AFS\" on, \"music High\", set the lift for 5 sec

Start raising the master fader \"again with ALL mics up to concert setting.. till the first feedback occurs, that should set the first filter.

raise it some more till the next one sets...and so on till you are SCREAMIN loud or the 6 filters are set...

The roamers should take care of the rest.

I mean I have guys running around out front with wireless mics and SCREAMIN at the top of their lungs, right in front of the speakers! and my monitors will rip your head off and you can point the mics RIGHT AT THE MONITORS...and no feedback...I've had performers walk up to a perfectly quite stage and bark into the mics and just about S**T themselves and get this big grin and say this is the first time EVER I have said this... but could you turn those things DOWN!

The technology does work... but my system is tuned to the nuts also....

I see DRA snuck in here...Yo thanks man...
Gadget

lazlo_funktek

Hi, hopefully you're all still listening..

I've just got the Driverack PA - which surprisingly is perfect for what I'm doing (amplified violin) - and I'd just like to know how the fixed frequencies get decided upon.

If you have no feedback and you set all the frequencies to fixed, what frequencies does it set them to?

Is setting the unit to all Live and turning off the reset the same as using all FIXED?

Thanks

Tom

Dra

Is setting the unit to all Live and turning off the reset the same as using all FIXED?

Essencially yes.
You have a bit of a quandry here. CAN you make it feed back? If not, don't even use it. By nature, the AFS may \"hear\" long notes as \"feedback\" and notch them out, whether fixed or life. The fixed filters are \"decided on\" by the frequencies that present themselves as feedback, which are typically mic'ed sources. If you select 8 fixed filters the DRPA AFS (if on) will notch out the first 8 \"feedbacks\" that it \"sees\" and permanently notch those during \"sound check\". The rest are for \"on the fly\" problems. , and are typically allowed to reset (roam) throughout the show. If you mic your violin, then I'd say use it, if a pick-up has been installed or it is an electronic violin, then most likely, not.

DRA

Gadget

But, realistically...if used as a fixed filter unit only.. set all 12 to fixed...and then with the system set up and ready to rock...with no input other than ambient sound, turn the system up WELL PAST THE NORMAL volume and see which filters set, you should be able to do any show without feedback...
G

lazlo_funktek

Hi thanks that answered my question. Think I might have a little play around with the Auto-EQ next...

Ivenblixt

What is this \"Gary's indoor EQ method\"?

Dra

Check the READ ME FIRST section. That why it is called the READ ME FIRST section. It is in there along with lots of other answers to commonly asked questions. ...or search \"indoor method\"

DRA

Gadget

Ya and it's really cool... with pictures and circles and arrows and a paragraph on the back of each one to be used as evidence against me in a court of law
G